UDR (UDR) 10-K 24 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 19, 2015
Entity Information [Line Items]
Entity Registrant Name	UDR, Inc.
Entity Central Index Key	74208
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float	$3
Entity Common Stock, Shares Outstanding		258,765,713
United Dominion Reality L.P.
Entity Information [Line Items]
Entity Registrant Name	United Dominion Realty L.P.
Entity Central Index Key	1018254
Document Period End Date	31-Dec-14
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Public Float
Entity Common Stock, Shares Outstanding		0

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Real estate owned:
Real estate held for investment	$8,205,627	$7,723,844
Less: accumulated depreciation	-2,434,772	-2,200,815
Real estate held for investment, net	5,770,855	5,523,029
Real estate under development (net of accumulated depreciation of $0 and $1,411, respectively)	177,632	466,002
Real estate sold or held for sale (net of accumulated depreciation of $0 and $6,568, respectively)	0	10,152
Total real estate owned, net of accumulated depreciation	5,948,487	5,999,183
Cash and cash equivalents	15,224	30,249
Restricted Cash and Investments, Current	22,340	22,796
Deferred financing costs, net	22,686	26,924
Notes receivable, net	14,369	83,033
Investment in and advances to unconsolidated joint ventures, net	718,226	507,655
Other assets	105,202	137,882
Total assets	6,846,534	6,807,722
Liabilities:
Secured debt	1,361,529	1,442,077
Unsecured debt	2,221,576	2,081,626
Real estate taxes payable	15,978	13,847
Accrued interest payable	34,215	32,279
Security deposits and prepaid rent	34,064	27,203
Distributions payable	69,460	61,907
Accounts payable, accrued expenses, and other liabilities	91,282	118,682
Total liabilities	3,828,104	3,777,621
Redeemable non-controlling interests in operating partnership	282,480	217,597
Equity
Preferred stock, no par value; 50,000,000 shares authorized	46,571	46,571
Common stock, $0.01 par value; 350,000,000 shares authorized 255,114,603 and 250,749,665 shares issued and outstanding December 31, 2014 and 2013, respectively	2,551	2,507
Additional paid-in capital	4,223,747	4,109,765
Distributions in excess of net income	-1,528,917	-1,342,070
Accumulated other comprehensive income/(loss), net	-8,855	-5,125
Total stockholders' equity	2,735,097	2,811,648
Non-controlling interest	853	856
Total equity	2,735,950	2,812,504
Total liabilities and equity	$6,846,534	$6,807,722

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Real estate owned:
Real estate under development, accumulated depreciation	$0	$1,411
Real estate held for sale, accumulated depreciation	$0	$6,568
Preferred stock, par or state value per share	$0	$0
Equity
Preferred stock, shares authorized	50,000,000	50,000,000
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	350,000,000	350,000,000
Common stock, shares issued	255,114,603	250,749,665
Common stock, shares outstanding	255,114,603	250,749,665
8.00% Series E Cumulative Convertible Preferred Stock
Equity
Preferred stock, shares issued	2,803,812	2,803,812
Preferred stock, shares outstanding	2,803,812	2,803,812
6.75% Series G Cumulative Redeemable Preferred Stock
Equity
Preferred stock, shares outstanding	0

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (Unaudited) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUES
Rental income	$805,002	$746,484	$704,701
Joint Venture Managment and Other Fees	13,044	12,442	11,911
Total revenues	818,046	758,926	716,612
Rental expenses:
Property operating and maintenance	149,428	144,319	139,784
Real estate taxes and insurance	99,175	93,765	86,154
Property management	22,138	20,528	19,378
Other operating expenses	8,271	7,136	5,718
Real estate depreciation and amortization	358,154	339,532	341,926
General and administrative	47,800	42,238	43,792
Casualty-related (recoveries)/charges, net	-541	12,253	-8,495
Other depreciation and amortization	5,775	6,741	4,105
Total operating expenses	691,282	642,006	649,352
Operating income	126,764	116,920	67,260
Income/(loss) from unconsolidated entities	-7,006	-415	-8,579
Interest Expense	-130,454	-126,083	-138,792
Interest and other income/(expense), net	11,858	4,619	3,524
Income/(loss) before income taxes, discontinued operations and gain/(loss) on sale of real estate owned	1,162	-4,959	-76,587
Tax benefit/(provision), net	-25,994	8,281	21,076
Income/(loss) from continuing operations	16,260	2,340	-46,305
Income/(loss) from discontinued operations, net of tax	10	43,942	266,608
Income (Loss) before Gain or Loss on Sale of Properties, and Extraordinary Items	16,270	46,282	220,303
Gain/(loss) on sales of real estate owned, net of tax	143,572	0	0
Net income/(loss)	159,842	46,282	220,303
Net (income)/loss attributable to redeemable non-controlling interests in the Operating Partnership	-5,511	-1,530	-7,986
Net income/(loss) attributable to non-controlling interests	-3	-60	140
Net income/(loss) attributable to Entity	154,334	44,812	212,177
Premium on preferred stock redemption or repurchases, net	0	0	-2,791
Net income/(loss) attributable to common stockholders	150,610	41,088	203,376
Earnings per weighted average common share - basic and diluted:
Income/(loss) from continuing operations attributable to common stockholders	$0.60	($0.01)	($0.22)
Income/(loss) from discontinued operations attributable to common stockholders	$0	$0.17	$1.07
Net income/(loss) attributable to common stockholders	$0.60	$0.16	$0.85
Income/(loss) from continuing operations attributable to common stockholders	$0.59	($0.01)	($0.22)
Income/(loss) from discontinued operations attributable to common stockholders	$0	$0.17	$1.07
Net income(loss) attributable to common stockholders	$0.59	$0.16	$0.85
Weighted average number of common shares outstanding b basic	251,528	249,969	238,851
Weighted average number of common shares outstanding b diluted	253,445	249,969	238,851
8.00% Series E Cumulative Convertible Preferred Stock
Rental expenses:
Distributions to preferred stockholders	-3,724	-3,724	-3,724
6.75% Series G Cumulative Redeemable Preferred Stock
Rental expenses:
Distributions to preferred stockholders	0	0	-2,286
Continuing Operations [Member]
Rental expenses:
Tax benefit/(provision), net	$15,098	$7,299	$30,282

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income / (Loss) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income/(loss)	$159,842	$46,282	$220,303
Other comprehensive income/(loss) - derivative instruments:
Unrealized holding gain/(loss)loss	-8,695	-469	-4,924
(Gain)/loss reclassified into earnings from other comprehensive income/(loss)	4,834	6,851	7,649
Other comprehensive income/(loss), including portion attributable to noncontrolling interests	-3,861	6,382	2,725
Comprehensive income/(loss)	155,981	52,664	223,028
Comprehensive (income)/loss attributable to noncontrolling interests	-5,375	-1,720	-8,206
Comprehensive income/(loss) attributable to UDR, Inc.	$150,606	$50,944	$214,822

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Equity (USD $)	Total	Preferred Stock	Common Stock	Paid - in Capital	Distributions in Excess of Net Income	Accumulated Other Comprehensive Income/(Loss)	Noncontrolling Interest
Beginning Balance at Dec. 31, 2011	$2,318,784,000	$128,180,000	$2,197,000	$3,340,470,000	($1,142,895,000)	($13,902,000)	$4,734,000
Beginning Balance, Shares at Dec. 31, 2011		6,068,174	219,650,225
Consolidated Statements of Changes in Equity
Net income	212,177,000				212,177,000
Net income/(loss) attributable to non-controlling interests	140,000						140,000
Other comprehensive (loss)/income	2,645,000					2,645,000
Issuance/(forfeiture) of common and restricted shares, net, Shares			-22,224
Issuance/(forfeiture) of common and restricted shares, net	-742,000		0	-742,000
Issuance of common shares through public offering, Shares			30,490,969
Issuance of common shares through public offering	756,138,000		305,000	755,833,000
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares		-3,264,362
Redemption of 6.75% Series G Cumulative Redeemable Shares	-81,609,000	-81,609,000		2,791,000	-2,791,000
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares			20,438
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership	529,000		-1,000	530,000
Acquisition of non-controlling interest	-4,871,000		0	0	0	0	-4,871,000
Increase in non-controlling interest from business combination, net	913,000						913,000
Common stock distributions declared	-215,654,000				-215,654,000	0
Preferred stock distributions declared-Series E	-3,724,000				-3,724,000	0
Preferred stock distributions declared-Series G	-2,286,000				-2,286,000	0
Adjustment to reflect redemption value of redeemable non-controlling interests	11,392,000				11,392,000	0
Ending Balance at Dec. 31, 2012	2,993,832,000	46,571,000	2,501,000	4,098,882,000	-1,143,781,000	-11,257,000	916,000
Ending Balance, Shares at Dec. 31, 2012		2,803,812	250,139,408
Consolidated Statements of Changes in Equity
Net income	44,812,000				44,812,000
Net income/(loss) attributable to non-controlling interests	-60,000						-60,000
Other comprehensive (loss)/income	6,132,000					6,132,000
Issuance/(forfeiture) of common and restricted shares, net, Shares			533,966
Issuance/(forfeiture) of common and restricted shares, net	9,072,000		5,000	9,067,000
Issuance of common shares through public offering	0
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares			76,291
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership	1,817,000		1,000	1,816,000
Acquisition of non-controlling interest							-4,900,000
Common stock distributions declared	-235,721,000				-235,721,000	0
Preferred stock distributions declared-Series E	-3,724,000				-3,724,000	0
Adjustment to reflect redemption value of redeemable non-controlling interests	-3,656,000				-3,656,000	0
Ending Balance at Dec. 31, 2013	2,812,504,000	46,571,000	2,507,000	4,109,765,000	-1,342,070,000	-5,125,000	856,000
Ending Balance, Shares at Dec. 31, 2013		2,803,812	250,749,665
Consolidated Statements of Changes in Equity
Net income	154,334,000				154,334,000
Net income/(loss) attributable to non-controlling interests	-3,000						-3,000
Other comprehensive (loss)/income	-3,730,000					-3,730,000
Issuance/(forfeiture) of common and restricted shares, net, Shares			801,054
Issuance/(forfeiture) of common and restricted shares, net	9,805,000		8,000	9,797,000
Issuance of common shares through public offering, Shares			3,410,433
Issuance of common shares through public offering	99,849,000		34,000	99,815,000
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares		0
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares	153,451		153,451
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership	4,372,000		2,000	4,370,000
Common stock distributions declared	-263,503,000				-263,503,000
Preferred stock distributions declared-Series E	-3,724,000				-3,724,000
Adjustment to reflect redemption value of redeemable non-controlling interests	-73,954,000				-73,954,000
Ending Balance at Dec. 31, 2014	$2,735,950,000	$46,571,000	$2,551,000	$4,223,747,000	($1,528,917,000)	($8,855,000)	$853,000
Ending Balance, Shares at Dec. 31, 2014		2,803,812	255,114,603

Consolidated_Statements_of_Cha1

Consolidated Statements of Changes in Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Common distributions declared per share	$1.04	$0.94	$0.88
Preferred Stock
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares	0		3,264,362
6.75% Series G Cumulative Redeemable Preferred Stock
Preferred stock distributions declared	$0	$0	$0.57
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares			3,264,362
8.00% Series E Cumulative Convertible Preferred Stock
Preferred stock distributions declared	$1.33	$1.33	$1.33

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (Unaudited) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Activities
Net income/(loss)	$159,842	$46,282	$220,303
Deprecation and Amortization, Including Discontinued Operations	363,929	348,231	354,505
Gain Loss on the Sale of Real Estate, Including Discontinued Operations	143,647	41,919	251,554
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Impairment loss, net of tax	0	1,470	0
Tax benefit/(provision), net	-15,136	-7,299	-30,282
Loss from unconsolidated entities	7,006	415	8,579
Casualty-related (recoveries)/charges, net	541	-270	8,495
Other	26,517	24,826	26,009
Changes in operating assets and liabilities:
Increase/(decrease) in operating assets	-1,074	-15,135	12,647
Increase/(decrease) in operating liabilites	-5,618	-16,699	-21,515
Net cash provided by operating activities	392,360	339,902	327,187
Investing Activities
Acquisition of real estate assets (net of liabilities assumed) and initial capital expenditures	-228,810	0	-108,215
Proceeds from sales of real estate investments, net	383,886	250,043	593,167
Development of real estate assets	-251,493	-280,603	-246,923
Capital expenditures and other major improvements - real estate assets, net of escrow reimbursement	-96,679	-153,676	-144,877
Capital expenditures - non-real estate assets	-5,497	-7,639	-7,947
Investment in unconsolidated joint ventures	-222,930	-43,291	-283,369
Distributions received from unconsolidated joint venture	59,199	130,984	50,580
(Issuance)/repayment of notes receivable	68,664	-19,027	-63,998
Net cash provided by/(used in) investing activities	-293,660	-123,209	-211,582
Financing Activities
Payments on secured debt	-80,961	-46,564	-491,885
Proceeds from the issuance of secured debt	5,502	0	250
Payments on unsecured debt	-312,500	-122,500	-100,000
Proceeds from the issuance of unsecured debt	298,956	299,943	396,400
Net (repayment)/borrowings of revolving bank debt	152,500	-76,000	-345,000
Proceeds from the issuance of common shares through public offering, net	99,849	0	756,138
Payments from the repurchase of Series G preferred stock, net	0	0	-81,609
Distributions paid to non-controlling interests	-9,929	-9,348	-9,033
Acquisition of nonredeemable noncontrolling interests	0	0	-4,871
Distributions paid to preferred stockholders	-3,724	-3,724	-6,954
Distributions paid to common stockholders	-256,100	-231,822	-207,470
Other	-7,318	-8,544	-21,959
Net cash (used in)/provided by financing activities	-113,725	-198,559	-115,993
Net increase in cash and cash equivalents	-15,025	18,134	-388
Cash and cash equivalents, beginning of period	30,249	12,115	12,503
Cash and cash equivalents, end of period	15,224	30,249	12,115
Supplemental Information:
Interest paid during the period, net of amounts capitalized	131,815	127,877	133,133
Non-cash transactions:
Real estate acquired in asset exchange or upon consolidation of joint ventures	0	129,437	0
Transfer of real estate owned to investment in and advances to unconsolidated ventures	54,938	175,951
Secured debt assumed in the acquisitions of properties, including asset exchange	0	63,595	34,412
Fair market value adjustment of secured debt assumed in acquisitions of properties, including asset exchange	0	0	2,617
Development costs and capital expenditures incurred but not yet paid	34,746	37,220	24,551
Contribution of purchase deposit made in 2011 to unconsolidated joint venture	0	0	80,397
Conversion of operating partnership non-controlling interests to common stock (18,440 shares in 2012 and 4,453 shares in 2011)	4,372	1,817	529
Unconsolidated Joint Venture Vitruvian Park [Member]
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Loss from unconsolidated entities	4,068	2,851	0
Non-cash transactions:
Transfer of real estate owned to investment in and advances to unconsolidated ventures			$0

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows (Unaudited) (Parenthetical)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Non-cash transactions:
Number of shares of common stock converted from operating partnership non-controlling interests	153,451	76,291	20,438

Consolidated_Balance_Sheets_UN

Consolidated Balance Sheets (UNITED DOMINION REALTY, L.P) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Real estate owned:
Real estate held for investment	$8,205,627,000	$7,723,844,000
Less: accumulated depreciation	-2,434,772,000	-2,200,815,000
Real estate held for investment, net	5,770,855,000	5,523,029,000
Real estate under development (net of accumulated depreciation of $0)	177,632,000	466,002,000
Total real estate owned, net of accumulated depreciation	5,948,487,000	5,999,183,000
Cash and cash equivalents	15,224,000	30,249,000
Restricted Cash and Investments, Current	22,340,000	22,796,000
Deferred financing costs, net	22,686,000	26,924,000
Other assets	105,202,000	137,882,000
Total assets	6,846,534,000	6,807,722,000
LIABILITIES AND CAPITAL
Secured debt	1,361,529,000	1,442,077,000
Real estate taxes payable	15,978,000	13,847,000
Accrued interest payable	34,215,000	32,279,000
Security deposits and prepaid rent	34,064,000	27,203,000
Distributions payable	69,460,000	61,907,000
Deferred gains on the sale of depreciable property	24,683,000	25,400,000
Accounts payable, accrued expenses, and other liabilities	91,282,000	118,682,000
Total liabilities	3,828,104,000	3,777,621,000
Partners' Capital:
Accumulated other comprehensive loss	-8,855,000	-5,125,000
Total liabilities and equity	6,846,534,000	6,807,722,000
United Dominion Reality L.P.
Real estate owned:
Real estate held for investment	4,238,770,000	4,108,417,000
Less: accumulated depreciation	-1,403,303,000	-1,241,574,000
Real estate held for investment, net	2,835,467,000	2,866,843,000
Real estate under development (net of accumulated depreciation of $0)	0	80,063,000
Total real estate owned, net of accumulated depreciation	2,835,467,000	2,946,906,000
Cash and cash equivalents	502,000	1,897,000
Restricted Cash and Investments, Current	13,811,000	13,526,000
Deferred financing costs, net	4,475,000	5,848,000
Other assets	24,029,000	25,064,000
Total assets	2,878,284,000	2,993,241,000
LIABILITIES AND CAPITAL
Secured debt	931,959,000	934,865,000
Notes payable due to General Partner	88,696,000	88,696,000
Real estate taxes payable	7,061,000	6,228,000
Accrued interest payable	3,284,000	3,323,000
Security deposits and prepaid rent	18,387,000	14,172,000
Distributions payable	47,788,000	43,253,000
Deferred gains on the sale of depreciable property	24,622,000	63,838,000
Accounts payable, accrued expenses, and other liabilities	22,436,000	35,769,000
Total liabilities	1,144,233,000	1,190,144,000
Partners' Capital:
General partner: 110,883 OP units outstanding at December 31, 2014 and 2013	1,105,000	1,163,000
Limited partners: 183,167,815 OP Units outstanding at December 31, 2014 and 2013	1,702,971,000	1,797,836,000
Accumulated other comprehensive loss	-1,075,000	-3,065,000
Total partners' capital	1,703,001,000	1,795,934,000
Advances to/(from) General Partner	13,624,000	-9,916,000
Non-controlling interest	17,426,000	17,079,000
Total capital	1,734,051,000	1,803,097,000
Total liabilities and equity	$2,878,284,000	$2,993,241,000

Consolidated_Balance_Sheets_UN1

Consolidated Balance Sheets (UNITED DOMINION REALTY, L.P) (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Real estate under development, accumulated depreciation	$0	$1,411
Real estate owned:
Real estate held for sale, accumulated depreciation	0	6,568
Partners' Capital:
OP units outstanding related to limited partner	183,278,698	183,278,698
United Dominion Reality L.P.
Real estate under development, accumulated depreciation	0	0
Real estate owned:
Real estate held for sale, accumulated depreciation	$0	$0
Partners' Capital:
OP units outstanding related to operating partnership	183,278,698	183,278,698
OP units outstanding related to general partner	110,883	110,883
OP units outstanding related to limited partner	183,167,815	183,167,815

Consolidated_Statements_of_Ope1

Consolidated Statements of Operations (UNITED DOMINION REALTY, L.P) (USD $)	12 Months Ended
Share data in Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Rental expenses:
Property operating and maintenance	$149,428,000	$144,319,000	$139,784,000
Real estate taxes and insurance	-99,175,000	-93,765,000	-86,154,000
Property management	-22,138,000	-20,528,000	-19,378,000
Other operating expenses	-8,271,000	-7,136,000	-5,718,000
Real estate depreciation and amortization	-358,154,000	-339,532,000	-341,926,000
General and administrative	-47,800,000	-42,238,000	-43,792,000
Casualty-related (recoveries)/charges, net	541,000	-12,253,000	8,495,000
Total operating expenses	691,282,000	642,006,000	649,352,000
Operating Income (Loss)	126,764,000	116,920,000	67,260,000
Income/(loss) from continuing operations	16,260,000	2,340,000	-46,305,000
Income/(loss) from discontinued operations	10,000	43,942,000	266,608,000
Gain/(loss) on sales of real estate owned	143,572,000	0	0
Net income/(loss)	159,842,000	46,282,000	220,303,000
Net (income)/loss attributable to non-controlling interests	-5,375,000	-1,720,000	-8,206,000
Net income/(loss) attributable to Entity	154,334,000	44,812,000	212,177,000
United Dominion Reality L.P.
REVENUES
Rental income	422,634,000	401,853,000	384,946,000
Rental expenses:
Property operating and maintenance	75,211,000	75,019,000	72,843,000
Real estate taxes and insurance	-47,110,000	-45,139,000	-40,866,000
Property management	-11,622,000	-11,051,000	-10,587,000
Other operating expenses	-5,172,000	-5,728,000	-5,272,000
Real estate depreciation and amortization	-179,176,000	-179,367,000	-191,731,000
General and administrative	-28,541,000	-24,808,000	-26,204,000
Casualty-related (recoveries)/charges, net	541,000	-8,083,000	5,518,000
Total operating expenses	347,373,000	333,029,000	353,021,000
Operating Income (Loss)	75,261,000	68,824,000	31,925,000
Interest expense	37,114,000	34,989,000	43,277,000
Interest expense on note payable due to General Partner	4,603,000	1,069,000	1,957,000
Income/(loss) from continuing operations	33,544,000	32,766,000	-13,309,000
Income/(loss) from discontinued operations	0	45,176,000	57,643,000
Income/(loss) before gain/(loss) on sale of real estate owned	33,544,000	77,942,000	44,334,000
Gain/(loss) on sales of real estate owned	63,635,000	0	0
Net income/(loss)	97,179,000	77,942,000	44,334,000
Net (income)/loss attributable to non-controlling interests	-952,000	-4,566,000	-352,000
Net income/(loss) attributable to Entity	$96,227,000	$73,376,000	$43,982,000
Income/(loss) per OP unit- basic and diluted:
Income/(loss) from continuing operations attributable to OP unitholders	$0.53	$0.16	($0.07)
Income/(loss) from discontinued operations attributable to OP unitholders	$0	$0.24	$0.31
Net income/(loss) attributable to OP unitholders	$0.53	$0.40	$0.24
Weighted average OP units outstanding - basic and diluted	183,279	184,196	184,281

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income / (Loss) (UNITED DOMINION REALTY, L.P.) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income/(loss)	$159,842	$46,282	$220,303
Other comprehensive income/(loss), including portion attributable to noncontrolling interests:
Unrealized holding gain/(loss)loss	-8,695	-469	-4,924
(Gain)/loss reclassified into earnings from other comprehensive income/(loss)	4,834	6,851	7,649
Other comprehensive income/(loss), including portion attributable to noncontrolling interests	-3,861	6,382	2,725
Comprehensive income/(loss)	155,981	52,664	223,028
Comprehensive (income)/loss attributable to noncontrolling interests	-5,375	-1,720	-8,206
Comprehensive income/(loss) attributable to UDR, Inc.	150,606	50,944	214,822
United Dominion Reality L.P.
Net income/(loss)	97,179	77,942	44,334
Other comprehensive income/(loss), including portion attributable to noncontrolling interests:
Unrealized holding gain/(loss)loss	-285	-348	-1,898
(Gain)/loss reclassified into earnings from other comprehensive income/(loss)	2,275	2,652	3,431
Other comprehensive income/(loss), including portion attributable to noncontrolling interests	1,990	2,304	1,533
Comprehensive income/(loss)	99,169	80,246	45,867
Comprehensive (income)/loss attributable to noncontrolling interests	-952	-4,566	-352
Comprehensive income/(loss) attributable to UDR, Inc.	$98,217	$75,680	$45,515

Consolidated_Statements_of_Cha2

Consolidated Statements of Changes in Capital (UNITED DOMINION REALTY, L.P) (Unaudited) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
Increase (Decrease) in Partners' Capital [Roll Forward]
Other comprehensive income (loss)	($3,861)	$6,382	$2,725
United Dominion Reality L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	1,803,097	1,918,756		1,853,369
Distributions	-191,150	-173,716	-163,008
Noncash Or Part Noncash Distribution, Issued Value		-23,329	-77,041
OP Units issued for real estate	-77,041		0
Adjustment to reflect limited partners' capital at redemption value	0
Net income (loss)	97,179	77,942	44,334
Other comprehensive income (loss)	1,990	2,304	1,533
Net change in receivable due from General Partner	22,935	54,852	182,528
Balance	1,734,051	1,803,097	1,918,756	1,853,369
United Dominion Reality L.P. | Payable/(Receivable) due to/(from) General Partner [Member] [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	-9,916
Net change in receivable due from General Partner	23,540
United Dominion Reality L.P. | Accumulated Other Comprehensive Income/(Loss)
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	-3,065	-5,369		-6,902
Other comprehensive income (loss)	1,990	2,304	1,533
Balance	-1,075	-3,065	-5,369	-6,902
United Dominion Reality L.P. | Total Partner's Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	1,795,934	1,917,299		2,034,792
Distributions	-191,150	-173,716	-163,008
Noncash Or Part Noncash Distribution, Issued Value	0	-23,329	0
OP Units issued for real estate		-23,329	0
Adjustment to reflect limited partners' capital at redemption value	0
Net income (loss)	96,227	73,376	43,982
Other comprehensive income (loss)	1,990	2,304	1,533
Balance	1,703,001	1,795,934	1,917,299	2,034,792
United Dominion Reality L.P. | Receivable Due From General Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance		-11,056		-193,584
Noncash Or Part Noncash Distribution, Issued Value			-53,712
Net change in receivable due from General Partner		54,852	182,528
Balance	13,624		-11,056	-193,584
United Dominion Reality L.P. | Noncontrolling Interest
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	17,079	12,513		12,161
Net income (loss)	952	4,566	352
Balance	17,426	17,079	12,513	12,161
United Dominion Reality L.P. | Class A Limited Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	40,902	41,656		43,967
Distributions	-2,328	-2,324	-2,328
Adjustment to reflect limited partners' capital at redemption value	14,493	702	-596
Net income (loss)	920	868	613
Balance	53,987	40,902	41,656	43,967
United Dominion Reality L.P. | Limited Partners
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	176,695	181,762		192,508
Distributions	-7,789	-7,118	-6,738
OP Unit Redemptions for common shares of UDR	-4,371	-1,817	-529
OP Units issued for real estate			-133
Adjustment to reflect limited partners' capital at redemption value	60,020	852	-5,166
Net income (loss)	3,938	3,016	1,820
Balance	228,493	176,695	181,762	192,508
United Dominion Reality L.P. | Limited Partner [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	1,580,239	1,698,027		1,803,926
Distributions	-180,917	-164,170	-153,846
OP Unit Redemptions for common shares of UDR	4,371	1,817	529
Noncash Or Part Noncash Distribution, Issued Value		-23,329
OP Units issued for real estate			133
Adjustment to reflect limited partners' capital at redemption value	-74,513	-1,554	5,762
Net income (loss)	91,311	69,448	41,523
Balance	1,420,491	1,580,239	1,698,027	1,803,926
United Dominion Reality L.P. | General Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance	1,163	1,223		1,293
Distributions	-116	-104	-96
Net income (loss)	58	44	26
Balance	1,105	1,163	1,223	1,293
Receivable Due From General Partner [Member] | United Dominion Reality L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
OP Units issued for real estate	($53,712)

Consolidated_Statements_of_Cas2

Consolidated Statements of Cash Flows (UNITED DOMINION REALTY, L.P) (Unaudited) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Casualty-related (recoveries)/charges noncash income	($541)	$270	($8,495)
Document Period End Date	31-Dec-14
Operating Activities
Net income/(loss)	159,842	46,282	220,303
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Other	26,517	24,826	26,009
Changes in operating assets and liabilities:
Increase/(decrease) in operating assets	-1,074	-15,135	12,647
Increase/(decrease) in operating liabilites	-5,618	-16,699	-21,515
Net cash provided by operating activities	392,360	339,902	327,187
Gain/(loss) on sales of real estate owned	143,572	0	0
Investing Activities
Development of real estate assets	-251,493	-280,603	-246,923
Payments for Capital Improvements	96,679	153,676	144,877
Net cash provided by/(used in) investing activities	-293,660	-123,209	-211,582
Financing Activities
Proceeds from the issuance of secured debt	5,502	0	250
Payments on secured debt	-80,961	-46,564	-491,885
Net cash (used in)/provided by financing activities	-113,725	-198,559	-115,993
Net increase in cash and cash equivalents	-15,025	18,134	-388
Cash and cash equivalents, beginning of period	30,249	12,115	12,503
Cash and cash equivalents, end of period	15,224	30,249	12,115
Supplemental Information:
Interest paid during the period, net of amounts capitalized	131,815	127,877	133,133
Properties acquired, including intangibles in asset exchange	0	129,437	0
Properties disposed in asset exchange, net of accumulated depreciation	54,938	175,951
Secured debt assumed in the acquisitions of properties, including asset exchange	0	63,595	34,412
Reallocation of Credit Facilities Debt from General Partner	0	13,682	0
United Dominion Reality L.P.
Casualty-related (recoveries)/charges noncash income	-541	270
Document Period End Date	31-Dec-14
Operating Activities
Net income/(loss)	97,179	77,942	44,334
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Depreciation and amortization	179,176	181,302	195,051
Hurricane-related recovery noncash income			5,518
Other	1,956	2,097	3,624
Changes in operating assets and liabilities:
Increase/(decrease) in operating assets	-1,756	-11,685	-1,543
Increase/(decrease) in operating liabilites	-5,429	478	5,205
Net cash provided by operating activities	208,032	208,346	201,095
Gain/(loss) on sales of real estate owned	63,635	0	0
Investing Activities
Development of real estate assets	-47,220	-66,407	-36,804
Payments for Capital Improvements	47,352	76,984
Proceeds from sales of real estate investments, net	47,922	79,437	113,175
Capital expenditures and other major improvements b real estate assets, net of escrow reimbursement			-72,098
Net cash provided by/(used in) investing activities	-46,650	-63,954	4,273
Financing Activities
Advances from General Partner, net	-153,751	-92,537	29,391
Proceeds from the issuance of secured debt	5,909	0	26,054
Payments on secured debt	-4,995	-42,237	-249,680
Distributions paid to partnership unitholders	-9,929	-9,348	-9,033
Payment of financing costs	-11	-1,177	0
Net cash (used in)/provided by financing activities	-162,777	-145,299	-203,268
Net increase in cash and cash equivalents	-1,395	-907	2,100
Cash and cash equivalents, beginning of period	1,897	2,804
Cash and cash equivalents, end of period	502	1,897	2,804
Supplemental Information:
Interest paid during the period, net of amounts capitalized	44,629	42,506	48,545
Noncash Or Part Noncash Distribution, Issued Value		-23,329	-77,041
OP Units issued in partial consideration for property acquisition	77,041		0
Capital Expenditures Incurred but Not yet Paid	7,254	6,371	7,440
UDR Pacific Los Alisos, LP [Member] | United Dominion Reality L.P.
Supplemental Information:
Properties disposed in asset exchange, net of accumulated depreciation	0	74,586	0
Partnership Capital [Member] | United Dominion Reality L.P.
Supplemental Information:
Noncash Or Part Noncash Distribution, Issued Value	0	-23,329	0
OP Units issued in partial consideration for property acquisition		23,329	0
All [Member] | United Dominion Reality L.P.
Changes in operating assets and liabilities:
Gain/(loss) on sales of real estate owned		($41,518)	$51,094

Consolidation_and_Basis_of_Pre

Consolidation and Basis of Presentation	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
CONSOLIDATION AND BASIS OF PRESENTATION	CONSOLIDATION AND BASIS OF PRESENTATION
	Organization and Formation
	UDR, Inc. (“UDR,” the “Company,” “we,” or “our”) is a self-administered real estate investment trust, or REIT, that owns, operates, acquires, renovates, develops, redevelops, and manages apartment communities generally in high barrier-to-entry markets located in the United States. The high barrier-to-entry markets are characterized by limited land for new construction, difficult and lengthy entitlement process, expensive single-family home prices and significant employment growth potential. At December 31, 2014, our consolidated apartment portfolio consisted of 139 consolidated communities located in 20 markets consisting of 39,851 apartment homes. In addition, the Company has an ownership interest in 10,055 apartment homes through unconsolidated joint ventures.
	Basis of Presentation
	The accompanying consolidated financial statements of UDR include its wholly-owned and/or controlled subsidiaries (see the “Consolidated Joint Ventures” section of Note 5, Joint Ventures and Partnerships, for further discussion). All significant intercompany accounts and transactions have been eliminated in consolidation. Certain previously reported amounts have been reclassified to conform to the current financial statement presentation.
	The accompanying consolidated financial statements include the accounts of UDR and its subsidiaries, including United Dominion Realty, L.P. (the “Operating Partnership” or the “OP”). As of December 31, 2014 and 2013, there were 183,278,698 units in the Operating Partnership outstanding, of which 174,113,225 or 95.0% and 173,959,774 or 94.9%, respectively, were owned by UDR and 9,165,473 or 5.0% and 9,318,924 or 5.1%, respectively, were owned by limited partners. The consolidated financial statements of UDR include the noncontrolling interests of the unitholders in the Operating Partnership.
	The Company evaluated subsequent events through the date its financial statements were issued. No significant recognized or non-recognized subsequent events were noted other than those mentioned in Note 5, Joint Ventures and Partnerships, and Note 8, Stockholders’ Equity.

Significant_Accounting_Policie

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
SIGNIFICANT ACCOUNTING POLICIES	SIGNIFICANT ACCOUNTING POLICIES
	Recent Accounting Pronouncements
	In April 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, which incorporates a requirement that a disposition represent a strategic shift in an entity’s operations into the definition of a discontinued operation. In accordance with the ASU, a discontinued operation represents (1) a component of an entity or group of components that has been disposed of or is classified as held for sale in a single transaction and represents a strategic shift that has or will have a major effect on an entity’s financial results, or (2) an acquired business that is classified as held for sale on the date of acquisition. A strategic shift could include a disposal of (1) a separate major line of business, (2) a separate major geographic area of operations, (3) a major equity method investment, or (4) other major parts of an entity. The standard requires prospective application and will be effective for interim and annual periods beginning on or after December 15, 2014, with early adoption permitted. The early adoption provision excludes components of an entity that were sold or classified as held for sale prior to the adoption of the standard.
	The Company elected to early adopt this standard effective January 1, 2014, which had a significant impact on the Company’s consolidated financial statements as further discussed in Note 3, Discontinued Operations. Subsequent to the Company’s adoption of ASU 2014-08, the sale of real estate that does not meet the definition of a discontinued operation under the standard is included in Gain/(loss) on sale of real estate owned, net of tax on the Consolidated Statements of Operations.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The updated standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The standard specifically excludes lease contracts. The ASU allows for the use of either the full or modified retrospective transition method, and the standard will be effective for the Company on January 1, 2017; early adoption is not permitted. The Company has not yet selected a transition method and we are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures.
	Real Estate
	Real estate assets held for investment are carried at historical cost and consist of land, buildings and improvements, furniture, fixtures and equipment and other costs incurred during their development, acquisition and redevelopment.
	Expenditures for ordinary repair and maintenance costs are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to the acquisition and/or improvement of real estate assets are capitalized and depreciated over their estimated useful lives if the expenditures qualify as a betterment or the life of the related asset will be substantially extended beyond the original life expectancy.
	UDR purchases real estate investment properties and records the tangible and identifiable intangible assets and liabilities acquired based on their estimated fair value. The primary, although not only, identifiable intangible asset associated with our portfolio is the value of existing lease agreements. When recording the acquisition of a community, we first assign fair value to the estimated intangible value of the existing lease agreements and then to the estimated value of the land, building and fixtures assuming the community is vacant. The Company estimates the intangible value of the lease agreements by determining the lost revenue associated with a hypothetical lease-up. Depreciation on the building is based on the expected useful life of the asset and the in-place leases are amortized over their remaining average contractual life. Property acquisition costs are expensed as incurred.
	Quarterly or when changes in circumstances warrant, UDR will assess our real estate properties for indicators of impairment. In determining whether the Company has indicators of impairment in our real estate assets, we assess whether the long-lived asset’s carrying value exceeds the community’s undiscounted future cash flows, which is representative of projected net operating income (“NOI”) plus the residual value of the community. Our future cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. If such indicators of impairment are present and the carrying value exceeds the undiscounted cash flows of the community, an impairment loss is recognized equal to the excess of the carrying amount of the asset over its estimated fair value. Our estimates of fair market value represent our best estimate based primarily upon unobservable inputs related to rental rates, operating costs, growth rates, discount rates, capitalization rates, industry trends and reference to market rates and transactions.
	For long-lived assets to be disposed of, impairment losses are recognized when the fair value of the asset less estimated cost to sell is less than the carrying value of the asset. Properties classified as real estate held for sale generally represent properties that are actively marketed or contracted for sale with the closing expected to occur within the next twelve months. Real estate held for sale is carried at the lower of cost, net of accumulated depreciation, or fair value, less the cost to sell, determined on an asset-by-asset basis. Expenditures for ordinary repair and maintenance costs on held for sale properties are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to held for sale properties are capitalized at cost. Depreciation is not recorded on real estate held for sale.
	Depreciation is computed on a straight-line basis over the estimated useful lives of the related assets which are 35 to 55 years for buildings, 10 to 35 years for major improvements, and 3 to 10 years for furniture, fixtures, equipment, and other assets.
	Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation. The Company capitalizes costs directly related to the predevelopment, development, and redevelopment of a capital project, which include, but are not limited to, interest, real estate taxes, insurance, and allocated development and redevelopment overhead related to support costs for personnel working on the capital projects. We use our professional judgment in determining whether such costs meet the criteria for capitalization or must be expensed as incurred. These costs are capitalized only during the period in which activities necessary to ready an asset for its intended use are in progress and such costs are incremental and identifiable to a specific activity to get the asset ready for its intended use. These costs, excluding the direct costs of development and redevelopment and capitalized interest, for the years ended December 31, 2014, 2013, and 2012 were $9.0 million, $11.1 million and $10.0 million, respectively. During the years ended December 31, 2014, 2013, and 2012, total interest capitalized was $20.2 million, $29.4 million, and $26.4 million, respectively. As each home in a capital project is completed and becomes available for lease-up, the Company ceases capitalization on the related portion and depreciation commences over the estimated useful life.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash on hand, demand deposits with financial institutions and short-term, highly liquid investments. We consider all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The majority of the Company’s cash and cash equivalents are held at major commercial banks.
	Restricted Cash
	Restricted cash consists of escrow deposits held by lenders for real estate taxes, insurance and replacement reserves, and security deposits.
	Revenue and Real Estate Sales Gain Recognition
	Rental income related to leases is recognized on an accrual basis when due from residents and tenants in accordance with GAAP. Rental payments are generally due on a monthly basis and recognized when earned. The Company recognizes interest income, management and other fees and incentives when earned, and the amounts are fixed and determinable.
	For sale transactions meeting the requirements for full accrual profit recognition, we remove the related assets and liabilities from our Consolidated Balance Sheets and record the gain or loss in the period the transaction closes. For sale transactions that do not meet the full accrual sale criteria due to our continuing involvement, we evaluate the nature of the continuing involvement and account for the transaction under an alternate method of accounting. Unless certain limited criteria are met, non-monetary transactions, including property exchanges, are accounted for at fair value.
	Sales to entities in which we retain or otherwise own an interest are accounted for as partial sales. If all other requirements for recognizing profit under the full accrual method have been satisfied and no other forms of continuing involvement are present, we recognize profit proportionate to the outside interest in the buyer and defer the gain on the interest we retain. The Company recognizes any deferred gain when the property is sold to a third party. In transactions accounted for by us as partial sales, we determine if the buyer of the majority equity interest in the venture was provided a preference as to cash flows in either an operating or a capital waterfall. If a cash flow preference has been provided, we recognize profit only to the extent that proceeds from the sale of the majority equity interest exceed costs related to the entire property.
	Notes Receivable
	The following table summarizes our notes receivable, net as of December 31, 2014 and 2013 (dollars in thousands):
		Interest rate at December 31, 2014		Balance Outstanding
				December 31, 2014		December 31, 2013
	Note due June 2014 (a)			$	—	$	40,800
	Note due February 2017 (b)	10	%	11,869		14,580
	Note due July 2017 (c)	8	%	2,500		1,400
	Note due June 2022 (net of discount of $0 and $247, respectively) (d)			—		26,253
	Total notes receivable, net			$	14,369	$	83,033
	(a) In the fourth quarter of 2013, in conjunction with the sale of its 95% interest in the Lodge at Stoughton, one of its unconsolidated joint ventures, the Company provided the buyer with a $40.8 million loan secured by the property at LIBOR plus a spread of 350 basis points with two three-month extension options at increased rates and a financing fee. In June 2014, the note was paid in full.
	(b) The Company has a secured note receivable with an unaffiliated third party with an aggregate commitment of $11.9 million, which bears an interest rate of 10.00% per annum. During the year ended December 31, 2014, the Company loaned an additional $1.2 million and received a payment of $3.9 million in the fourth quarter under this note. Interest payments are due monthly. The note matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) the fifth anniversary of the date of the note (February 2017).
	(c) The Company has a secured note receivable with an unaffiliated third party with an aggregate commitment of $2.5 million, which bears an interest rate of 8.00% per annum. During the year ended December 31, 2014, the Company loaned an additional $1.1 million under the note. Interest payments are due monthly. The note matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) the fifth anniversary of the date of the note (July 2017).
	(d) In 2012, the Company purchased a "B" Note secured by a first mortgage on a class A community in West Los Angeles. The $26.5 million loan was purchased at a yield of 7.25% and bore a coupon rate of 7.00%. Interest payments are due monthly and the note is due June 2022. The discount is amortized using the effective interest method. In July 2014, the Company received proceeds of $36.0 million from the repayment of this note, resulting in a net gain of approximately $8.4 million, which is included in Interest and other income/(expense), net on the Consolidated Statements of Operations.
	During the years ended December 31, 2014, 2013 and 2012, the Company recognized $3.4 million, $4.1 million and $2.7 million, respectively, of interest income from these notes receivable, of which $0, $765,000 and $281,000, respectively, were related party interest income. Interest income is included in Interest and other income/(expense), net on the Consolidated Statements of Operations.
	Investment in Joint Ventures and Partnerships
	We use the equity method to account for investments in joint ventures and partnerships that qualify as variable interest entities where we are not the primary beneficiary and entities that we do not control or where we do not own a majority of the economic interest but have the ability to exercise significant influence over the operating and financial policies of the investee. Throughout these financial statements we use the term “joint venture” or “partnership” when referring to investments in entities in which we do not have a 100% ownership interest. The Company also uses the equity method when we function as the managing partner and our venture partner has substantive participating rights or where we can be replaced by our venture partner as managing partner without cause. For a joint venture or partnership accounted for under the equity method, our share of net earnings or losses is reflected as income/loss when earned/incurred and distributions are credited against our investment in the joint venture or partnership as received.
	In determining whether a joint venture or partnership is a variable interest entity, the Company considers: the form of our ownership interest and legal structure; the size of our investment; the financing structure of the entity, including necessity of subordinated debt; estimates of future cash flows; ours and our partner’s ability to participate in the decision making related to acquisitions, disposition, budgeting and financing of the entity; obligation to absorb losses and preferential returns; nature of our partner’s primary operations; and the degree, if any, of disproportionality between the economic and voting interests of the entity. As of December 31, 2014, the Company did not determine any of our joint ventures or partnerships to be variable interest entities.
	We evaluate our investments in unconsolidated joint ventures for events or changes in circumstances that indicate there may be an other-than-temporary decline in value. We consider various factors to determine if a decrease in the value of the investment is other-than-temporary. These factors include, but are not limited to, age of the venture, our intent and ability to retain our investment in the entity, the financial condition and long-term prospects of the entity, the fair value of the property of the joint venture, and the relationships with the other joint venture partners and its lenders. The amount of loss recognized is the excess of the investment’s carrying amount over its estimated fair value. If we believe that the decline in fair value is temporary, no impairment is recorded. The aforementioned factors are taken into consideration as a whole by management in determining the valuation of our equity method investments. Should the actual results differ from management’s judgment, the valuation could be negatively affected and may result in a negative impact to our Consolidated Financial Statements.
	Derivative Financial Instruments
	The Company utilizes derivative financial instruments to manage interest rate risk and generally designates these financial instruments as cash flow hedges. Derivative financial instruments are recorded on our Consolidated Balance Sheets as either an asset or liability and measured quarterly at their fair value. The changes in fair value for cash flow hedges that are deemed effective are reflected in other comprehensive income/(loss) and for non-designated derivative financial instruments in earnings. The ineffective component of cash flow hedges, if any, is recorded in earnings.
	Redeemable Noncontrolling Interests in the Operating Partnership
	Interests in the Operating Partnership held by limited partners are represented by Operating Partnership units (“OP Units”). The income is allocated to holders of OP Units based upon net income available to common stockholders and the weighted average number of OP Units outstanding to total common shares plus OP Units outstanding during the period. Capital contributions, distributions, and profits and losses are allocated to noncontrolling interests in accordance with the terms of the partnership agreement.
	Limited partners have the right to require the Operating Partnership to redeem all or a portion of the OP Units held by the limited partner at a redemption price equal to and in the form of the Cash Amount as defined in the Amended and Restated Agreement of Limited Partnership of the Operating Partnership (the “Operating Partnership Agreement”), provided that such OP Units have been outstanding for at least one year. UDR, as the general partner of the Operating Partnership may, in its sole discretion, purchase the OP Units by paying to the limited partner either the Cash Amount or the REIT Share Amount (generally one share of Common Stock of the Company for each OP Unit), as defined in the Operating Partnership Agreement. Accordingly, the Company records the OP Units outside of permanent equity and reports the OP Units at their redemption value using the Company’s stock price at each balance sheet date.
	Income Taxes
	Due to the structure of the Company as a REIT and the nature of the operations for the operating properties, no provision for federal income taxes has been provided for at UDR. Historically, the Company has generally incurred only state and local excise and franchise taxes. UDR has elected for certain consolidated subsidiaries to be treated as taxable REIT subsidiaries (“TRS”), primarily those engaged in development activities.
	Income taxes for our TRS are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rate is recognized in earnings in the period of the enactment date. The Company’s deferred tax assets are generally the result of differing depreciable lives on capitalized assets and timing of expense recognition for certain accrued liabilities. As of December 31, 2014 and 2013, UDR’s net deferred tax asset of $7.0 million, which had no valuation allowance, and $32.3 million, net of a valuation allowance of $1.3 million, respectively, was included in Other assets on the Consolidated Balance Sheets.
	Prior to 2012, our TRS had a history of losses and, as a result, historically recognized a valuation allowance for net deferred tax assets. Each quarter, the Company evaluates the need to retain all or a portion of the valuation allowance on its net deferred tax assets. In 2012, the Company determined that it was more likely than not that the deferred tax assets, including any remaining net operating loss carry forward, would be realized. In making this determination, the Company analyzed, among other things, its recent history of earnings from sales of depreciable property, forecasts of future earnings and its cumulative earnings for the last twelve quarters. The reversal of the valuation allowance resulted in an income tax benefit of $44.4 million during the year ended December 31, 2012, $21.5 million of which is reported in continuing operations and included within Tax benefit/(provision), net in the Consolidated Statements of Operations, and $22.9 million of which is included within Income/(loss) from discontinued operations, net of tax in the Consolidated Statements of Operations.
	GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition.
	The Company recognizes its tax positions and evaluates them using a two-step process. First, UDR determines whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The Company will determine the amount of benefit to recognize and record the amount that is more likely than not to be realized upon ultimate settlement.
	UDR had no material unrecognized tax benefit, accrued interest or penalties at December 31, 2014. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2010 through 2013 remain open to examination by tax jurisdictions to which we are subject. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in income tax expense.
	Discontinued Operations
	Prior to the adoption of ASU No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, the results of operations for those properties sold during the year or classified as held for sale at the end of the current year are classified as discontinued operations in the current and prior periods. Further, to meet the discontinued operations criteria, the Company will not have any significant continuing involvement in the ownership or operation of the property after the sale or disposition. Once a property is classified as held for sale, depreciation is no longer recorded. However, if the Company determines that the property no longer meets the criteria for held for sale, the Company will recapture any unrecorded depreciation on the property. The assets and liabilities, if any, of properties classified as held for sale are presented separately on the Consolidated Balance Sheets at the lower of their carrying amount or their estimated fair value less the costs to sell the assets. (See Note 3, Discontinued Operations and Assets Held for Sale, for further discussion).
	Stock-Based Employee Compensation Plans
	The Company measures the cost of employee services received in exchange for an award of an equity instrument based on the award’s fair value on the grant date and recognizes the cost over the period during which the employee is required to provide service in exchange for the award, which is generally the vesting period. The fair value for stock options issued by the Company is calculated utilizing the Black-Scholes-Merton formula. For performance based awards, the Company remeasures the fair value each balance sheet date with adjustments made on a cumulative basis until the award is settled and the final compensation is known. The fair value for market based awards issued by the Company is calculated utilizing a Monte Carlo simulation. For further discussion, see Note 9, Employee Benefit Plans.
	Advertising Costs
	All advertising costs are expensed as incurred and reported on the Consolidated Statements of Operations within the line item General and administrative. During the years ended December 31, 2014, 2013, and 2012, total advertising expense was $6.0 million, $5.7 million, and $6.2 million, respectively.
	Cost of Raising Capital
	Costs incurred in connection with the issuance of equity securities are deducted from stockholders’ equity. Costs incurred in connection with the issuance or renewal of debt are recorded based on the terms of the debt issuance or renewal. Accordingly, if the terms of the renewed or modified debt instrument are deemed to be substantially different (i.e. a 10 percent or greater difference in the cash flows between instruments), all unamortized financing costs associated with the extinguished debt are charged to earnings in the current period and certain costs of new debt issuances are capitalized and amortized over the term of the debt. When the cash flows are not substantially different, the lender costs associated with the renewal or modification are capitalized and amortized into interest expense over the remaining term of the related debt instrument and other related costs are expensed. The balance of any unamortized financing costs associated with retired debt is expensed upon retirement. Deferred financing costs for new debt instruments include fees and costs incurred by the Company to obtain financing. Deferred financing costs are generally amortized on a straight-line basis, which approximates the effective interest method, over a period not to exceed the term of the related debt.
	Preferred Share Redemption and Repurchases
	During the year ended December 31, 2012, the Company completed the redemption of all outstanding shares of its 6.75% Series G Cumulative Redeemable Preferred Stock. A total of 3,264,362 shares of the Series G Preferred Stock was redeemed at a redemption price of $25 per share in cash, plus accrued and unpaid dividends to the redemption date for a total cost of $82.1 million.
	When redeeming or repurchasing preferred stock, the Company recognizes share issuance costs as a charge to the preferred stock on a pro rata basis to the total costs incurred for the preferred stock as well as any premium or discount on the redemption or repurchase. In connection with the redemption of the Series G Preferred Stock, the Company recognized a (decrease)/increase in net income/(loss) attributable to common stockholders of $(2.8) million for the year ended December 31, 2012, which is reported in Premium on preferred stock redemption or repurchases, net on the Consolidated Statements of Operations.
	Comprehensive Income/(Loss)
	Comprehensive income/(loss), which is defined as the change in equity during each period from transactions and other events and circumstances from nonowner sources, including all changes in equity during a period except for those resulting from investments by or distributions to stockholders, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the years ended December 31, 2014, 2013, and 2012, the Company's other comprehensive income/(loss) consisted of the gain/(loss) (effective portion) on derivative instruments that are designated as and qualify as cash flow hedges, (gain)/loss on derivative instruments and marketable securities reclassified from other comprehensive income/(loss) into earnings, and the allocation of other comprehensive income/(loss) to redeemable noncontrolling interests. The (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) is included in interest expense in the accompanying Consolidated Statements of Operations. See Note 13, Derivatives and Hedging Activity, for further discussion. The (gain)/loss on marketable securities reclassified from other comprehensive income/(loss) is included in Interest and other income/(expense), net on the Consolidated Statements of Operations. The allocation of other comprehensive income/(loss) to redeemable noncontrolling interests during the years ended December 31, 2014, 2013, and 2012 was $(133,000), $250,000, and $80,000, respectively.
Use of Estimates
The preparation of these financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates.
Market Concentration Risk
The Company is subject to increased exposure from economic and other competitive factors specific to markets where the Company holds a significant percentage of the carrying value of its real estate portfolio. At December 31, 2014, the Company held greater than 10% of the carrying value of its real estate portfolio in the Orange County, California; Metropolitan D.C.; and New York, New York markets.

Real_Estate_Owned

Real Estate Owned	12 Months Ended
	Dec. 31, 2014
Real Estate [Abstract]
REAL ESTATE OWNED	REAL ESTATE OWNED
	Real estate assets owned by the Company consist of income producing operating properties, properties under development, land held for future development, and sold or held for sale properties. As of December 31, 2014, the Company owned and consolidated 139 communities in 10 states plus the District of Columbia totaling 39,851 apartment homes. The following table summarizes the carrying amounts for our real estate owned (at cost) as of December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Land and land improvements	$	1,980,221		$	1,847,127
	Depreciable property — held and used:
	Building, improvements, and furniture, fixtures and equipment	6,225,406			5,876,717
	Under development:
	Land	24,584			110,769
	Building, improvements, and furniture, fixtures and equipment	153,048			356,644
	Real estate held for disposition:
	Land	—			10,751
	Building, improvements, and furniture, fixtures and equipment	—			5,969
	Real estate owned	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Real estate owned, net	$	5,948,487		$	5,999,183
	During the year ended December 31, 2014, the Company sold nine communities consisting of a total of 2,500 apartment homes, an adjacent parcel of land, and one operating property for gross proceeds of $328.4 million, resulting in net proceeds of $324.4 million and a total gain, net of tax, of $138.6 million. A portion of the sale proceeds was designated for tax-deferred exchanges under Section 1031 of the Internal Revenue Code and was used to fund acquisitions of real estate as discussed below.
	In December 2014, the Company sold a 49% interest in 13th and Market and a 50% interest in 3033 Wilshire to MetLife for approximately $54.2 million and $8.3 million, respectively, and recognized, net of tax, a gain of $7.2 million and a loss of $2.2 million, respectively. Subsequent to the sale, the two communities are accounted for under the equity method of accounting and are included in Investment in and advances to unconsolidated joint ventures, net on the Consolidated Balance Sheets. See further discussion of this transaction in Note 5, Joint Ventures and Partnerships. The activity of the two communities prior to sale is classified as a component of continuing operations on the Consolidated Statements of Operations.
	In 2014, the Company acquired a fully-entitled land parcel for future development located in Huntington Beach, California for $77.8 million, two communities, located in Seattle, Washington and Kirkland, Washington, with a total of 358 apartment homes for $45.5 million and $75.2 million, respectively, a land parcel for future development located in Boston, Massachusetts for $32.2 million. The four acquisitions during the year ended December 31, 2014 were accomplished through tax-deferred exchanges under Section 1031 of the Internal Revenue Code.
	In June 2013, the Company sold a 50% interest in five partnerships (the “UDR/MetLife Vitruvian Park® Partnerships”) to MetLife for approximately $141.3 million, before transaction costs of $936,000. The properties held by the UDR/MetLife Vitruvian Park® Partnerships are located in Addison, Texas and consist of two operating communities with 739 apartment homes, one recently completed development community in lease-up with 391 apartment homes, and 28.4 acres of developable land parcels. The transaction resulted in a gain of approximately $436,000 which the Company has deferred until the terms of the construction completion guarantee have been met. The UDR/MetLife Vitruvian Park® Partnerships are accounted for under the equity method of accounting and are included in Investment In and Advances To Unconsolidated Joint Ventures, Net on the Consolidated Balance Sheets. See further discussion of this transaction in Note 5, Joint Ventures and Partnerships.
	The operations of the UDR/MetLife Vitruvian Park® Partnerships' assets, prior to the sale of a 50% interest, have been classified as a component of continuing operations on the Consolidated Statements of Operations, as UDR has continuing involvement over the duration of the partnership.
	In December 2013, the Company sold a 49% interest to MetLife in the Company’s fully-entitled 399 Fremont land parcel located in San Francisco, California for approximately $29.9 million. In conjunction with the sale, the Company formed a new unconsolidated joint venture, UDR/MetLife 399 Fremont, to develop a $318 million, 447-home, luxury high-rise tower on the site. As the Company recently acquired the 399 Fremont land parcel, the sale price was equivalent to the cost basis resulting in no gain or loss on the transaction. For more information on this transaction see Note 5, Joint Ventures and Partnerships.
	In December 2013, the Company became the managing partner of two joint ventures resulting in consolidation of both and increasing the real estate owned by $129.4 million. See Note 5, Joint Ventures and Partnerships, for further details.
	The Company incurred $373,000, $59,000 and $2.3 million of acquisition-related costs during the years ended December 31, 2014, 2013, and 2012, respectively. These expenses are reported within the line item General and Administrative on the Consolidated Statements of Operations.
	In February 2015, the Company acquired an office building in Highlands Ranch, Colorado, for total consideration of approximately $24.0 million, which was comprised of assumed debt. The Company’s corporate offices, as well as other leased office space, are located in the acquired building. The building consists of approximately 120,000 square feet, of which UDR occupies approximately 44,000 square feet. All existing leases were assumed by the Company at the time of the acquisition.

Joint_Ventures

Joint Ventures	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
JOINT VENTURES	JOINT VENTURES AND PARTNERSHIPS
	UDR has entered into joint ventures and partnerships with unrelated third parties to acquire real estate assets that are either consolidated and included in Real Estate Owned on the Consolidated Balance Sheets or are accounted for under the equity method of accounting, and are included in Investment in and Advances to Unconsolidated Joint Ventures, Net on the Consolidated Balance Sheets. The Company consolidates the entities that we control as well as any variable interest entity where we are the primary beneficiary. In addition, the Company consolidates any joint venture or partnership in which we are the general partner or managing partner and the third party does not have the ability to substantively participate in the decision-making process nor the ability to remove us as general partner or managing partner without cause.
	UDR’s joint ventures and partnerships are funded with a combination of debt and equity. Our losses are limited to our investment and except as noted below, the Company does not guarantee any debt, capital payout or other obligations associated with our joint ventures and partnerships.
	Consolidated Joint Ventures
	In December 2013, the Company consolidated its 95%/5% development joint ventures 13th and Market in San Diego, California and Domain College Park in Metropolitan, D.C. The consolidation was due to the Company becoming the managing partner of each of the joint ventures pursuant to amendments to the LLC Agreements. In connection with the amendments, our partner received equity distributions reducing its capital account balances to zero, the Company replaced our partner as the managing partner, and our partner no longer has the ability to substantively participate in the decision-making process, with only protective rights remaining. We accounted for the consolidations as asset acquisitions since the joint ventures were under development and not complete at the time of consolidation resulting in no gain or loss upon consolidation and increasing our real estate owned by $129.4 million and our debt owed by $63.6 million. In addition pursuant to the amendments, the Company paid a non-refundable deposit to our partner in January 2014 of $2.0 million for each joint venture, or $4.0 million in total, for the right to exercise options in 2014 to acquire our partner’s upside participation in the joint ventures. The non-refundable deposits were applied towards the total purchase price of approximately $24.7 million when the Company acquired 100% of the interest in the joint ventures in November 2014.
	In December 2014, the Company sold a 49% interest in 13th and Market to MetLife for $54.2 million, resulting in a gain, net of tax, of $7.2 million. Additionally, the Company sold a 50% interest in a wholly owned land parcel to MetLife for $8.3 million, resulting in a loss, net of tax, of $2.2 million. As a result, the Company no longer controls these two joint ventures and they were deconsolidated by the Company in December 2014.
	Unconsolidated Joint Ventures and Partnerships
	The Company recognizes earnings or losses from our investments in unconsolidated joint ventures and partnerships consisting of our proportionate share of the net earnings or losses of the joint ventures and partnerships. In addition, we may earn fees for providing management services to the unconsolidated joint ventures and partnerships.
	The following table summarizes the Company’s investment in and advances to unconsolidated joint ventures and partnerships, net, which are accounted for under the equity method of accounting as of December 31, 2014 and 2013 (dollars in thousands):
	Joint Venture		Location of Properties		Number of Properties	Number of Apartment Homes			Investment at								UDR’s Ownership Interest
					2014	2014			2014				2013				2014				2013
	Operating and development:
	UDR/MetLife I (a)		Various		4 land parcels	—			$	13,306			$	47,497			15.7			%	4.5			%
	UDR/MetLife II (a)		Various		21 operating communities	4,642			431,277				327,926				50			%	50			%
	Other UDR/MetLife Joint Ventures (a)		Various		1 operating community, 3 development communities (b), 2 land parcels	1,282			134,939				36,313				50.6			%	35.8			%
	UDR/MetLife Vitruvian Park® (c)		Addison, TX		3 operating communities, 6 land parcels	1,394			80,302				79,318				50			%	50			%
	UDR/KFH (d)		Washington, D.C.		3 operating communities	660			21,596				25,919				30			%	30			%
	Texas (e)		Texas		8 operating communities	3,359			(25,901		)		(23,591		)		20			%	20			%
	Investment in and advances to unconsolidated joint ventures, net, before participating loan investment								655,519				493,382
			Location		Preferred Return	Years To Maturity			Investment at								Income From Participating Loan Investment For The Year Ended
	Participating loan investment:								2014				2013				2014		2013			2012
	Steele Creek (f)		Denver, CO		6.50%	2.8			62,707				14,273				$2,350		$156			$—
	Total investment in and advances to unconsolidated joint ventures, net								$	718,226			$	507,655
	(a)	In January 2012, the Company formed a joint venture with an unaffiliated third party to acquire 399 Fremont (land for future development) in San Francisco, California, which is included in Other UDR/MetLife Joint Ventures in the table above. At closing, UDR owned a noncontrolling interest of 92.5% in the joint venture. The Company’s total investment was $55.5 million, which consisted of its initial investment of $37.3 million and an option to exercise its right to acquire its partner’s 7.5% ownership interest in the joint venture. In October 2012, the Company exercised its option and paid $13.5 million. In January 2013, the Company subsequently acquired its partner’s 7.5% ownership interest for $4.7 million. In December 2013, the Company sold a 49% ownership interest to MetLife in the fully-entitled 399 Fremont land parcel for approximately $29.9 million. In conjunction with the sale, the Company formed a new unconsolidated real estate joint venture with MetLife, UDR/MetLife 399 Fremont, to develop a $318 million, 447-home, luxury high-rise tower on the site. Construction commenced in the first quarter 2014. As the Company recently acquired the 399 Fremont land parcel, the sale price was equivalent to the cost basis resulting in no gain or loss on the transaction. Under the terms of the partnership, the Company serves as the general partner with significant participating rights held by our partner, and has the ability to earn fees for development management, property management, asset management, and financing transactions. The UDR/MetLife 399 Fremont Joint Venture is accounted for under the equity method of accounting. Our initial investment was approximately $31.1 million.
	In June 2013 and within UDR/MetLife I, the Company exchanged with MetLife its approximately 10% ownership interest in four operating communities and paid MetLife an additional $15.6 million in cash for an increased ownership interest of approximately 35% in two high-rise operating communities, bringing UDR's ownership interest in the two high-rise operating communities to 50% each. The two high-rise operating communities are located in Denver, Colorado and San Diego, California and were subsequently contributed to UDR/MetLife II. The four operating communities in which UDR exchanged its ownership interest are located in Washington D.C.; San Francisco, California; Dallas, Texas; and Charlotte, North Carolina. UDR continues to fee manage these four operating communities.
	In March 2014, the Company sold its minority ownership interests in two operating communities located in Los Angeles, California to MetLife for cash proceeds of $3.0 million, which resulted in an immaterial gain. In April 2014, the Company increased its ownership interest in the remaining six operating communities in the UDR/MetLife I Joint Venture from 12% to 50%, and MetLife and the Company contributed the communities to the UDR/MetLife II Joint Venture. The Company paid MetLife $82.5 million for the additional ownership interests. The Company continues to fee manage the operating communities that were contributed to the UDR/MetLife II Joint Venture as well as the two operating communities in which it sold its minority ownership interests.
	In July 2014, the Company increased the ownership interest in two land sites in UDR/Metlife I to 50.1% and formed individual asset joint ventures, which are included in Other UDR/MetLife Joint Ventures in the table above. The remaining 49.9% continues to be held by our joint venture partner MetLife. The Company paid MetLife approximately $21.5 million for the additional ownership interests.
	In December 2014, the Company increased its ownership interest in one land site in the UDR/MetLife I Joint Venture to 50%. Additionally, the Company increased its ownership interest in another land site to 50.1%, which MetLife and the Company contributed to a separate joint venture and is included in Other UDR/MetLife Joint Ventures in the table above. The Company paid MetLife approximately $15.3 million for the additional ownership interests. As of December 31, 2014, the remaining assets in the UDR/MetLife I Joint Venture were comprised of three potential development land sites in which the Company has an average ownership interest of approximately 5% and one fully entitled land parcel in which the Company owns 50%.
	In December 2014, the Company sold a 49% interest in 13th and Market located in San Diego, California to MetLife for gross proceeds of $54.2 million, resulting in a gain, net of tax, of $7.2 million and a 50% interest in 3033 Wilshire in Los Angeles, California, also to MetLife for gross proceeds of $8.3 million, resulting in a loss, net of tax, of $2.2 million.
	(b)	The number of apartment homes for the communities under development presented in the table above is based on the projected number of total homes. As of December 31, 2014, no apartment homes had been completed in Other UDR/MetLife Development Joint Ventures.
	(c)	In June 2013, the Company sold a 50% interest in five partnerships (the “UDR/MetLife Vitruvian Park® Partnerships”) to MetLife for approximately $141.3 million. The transaction resulted in a gain of approximately $436,000 which the Company has deferred until the terms of the construction completion guarantee have been met. Under the terms of the UDR/MetLife Vitruvian Park® Partnerships, the Company serves as the general partner with significant participating rights held by our partner, and earns fees for property management, asset management, and financing transactions. The UDR/MetLife Vitruvian Park® Partnerships are accounted for under the equity method of accounting. Our initial investment was approximately $80.2 million, which consisted of approximately $140.0 million (50% of our net book value of the real estate at the time of the transaction) reduced by our share of the net proceeds received upon encumbering the assets of approximately $58.7 million and other operating adjustments.
	At closing, a total of $118.3 million of secured debt was placed on the two operating communities and the community under development. The debt on the two operating communities carries an interest rate of 4.0% with a term of ten years and the non-recourse construction loan on the community under development carries an interest rate of LIBOR plus 175 basis points with a term of two years and two one-year extension options. The Company has guaranteed the completion of the construction of the development. Proceeds from the construction loan will be used for completion of construction of the development. Upon completion, at its 50% ownership, the Company's pro-rata share of the undepreciated book value of the UDR/MetLife Vitruvian Park® Partnerships' real estate assets and outstanding debt will be approximately $145.0 million and $62.8 million, respectively.
	(d) UDR is a partner with an unaffiliated third party, which formed a joint venture for the investment of up to $450 million in multifamily properties located in key, high barrier to entry markets. The partners will contribute equity of $180 million of which the Company’s maximum equity will be 30% or $54 million when fully invested.
	(e) In November 2007, UDR and an unaffiliated third party formed a joint venture to own and operate 10 communities located in Texas. UDR contributed cash and property equal to 20% of the fair value of the joint venture. During the year ended December 31, 2012, the Company acquired the remaining 80% ownership interests in two communities in Austin, Texas for $11.7 million. The Company’s investment in the joint venture at December 31, 2014 and 2013 was net of deferred profits on the sale of depreciable properties to the joint venture of $23.9 million and $24.0 million, respectively.
	In January 2015, the eight communities held by the Texas joint venture were sold, generating net proceeds to UDR of $43.5 million. The Company recorded promote and fee income of $9.6 million and a gain of $59.1 million (including $24.2 million of previously deferred gains) in connection with the sale.
	(f) In October 2013, the Company entered into a participating debt financing arrangement with a third party that is developing a $108 million, 218-home, high-rise luxury community located adjacent to the Cherry Creek Mall in Denver, Colorado. Under the agreement, UDR will finance up to 85%, or approximately $92.0 million, of the development cost at an interest rate of 6.5% per annum on the outstanding debt balance. In addition, the Company has the option to purchase the community upon completion of construction and has a 50% participating interest in the profit upon the acquisition of the community or sale to a third party. The Company accounts for the arrangement consistent with an investment in real estate under the equity method of accounting.
	As of December 31, 2014, and 2013, our participating loan investment was $62.7 million and $14.3 million, respectively, which was included in Investment in and advances to unconsolidated joint ventures, net on the Consolidated Balance Sheets. We also recognized $2.4 million and $156,000 of income included in Income/(loss) from unconsolidated entities on the Consolidated Statements of Operations for the years ended December 31, 2014 and 2013, respectively.
	As of December 31, 2014 and 2013, the Company had deferred fees and deferred profit from the sale of properties to joint ventures or partnerships of $24.7 million and $25.4 million, respectively, which will be recognized through earnings over the weighted average life of the related properties, upon the disposition of the properties to a third party, or upon completion of certain development obligations.
	The Company recognized $11.3 million, $11.2 million, and $11.8 million of management fees during the years ended December 31, 2014, 2013, and 2012, respectively, for our management of the joint ventures and partnerships. The management fees are included in Joint venture management and other fees on the Consolidated Statements of Operations.
	The Company may, in the future, make additional capital contributions to certain of our joint ventures and partnerships should additional capital contributions be necessary to fund acquisitions or operations.
	We evaluate our investments in unconsolidated joint ventures and partnerships when events or changes in circumstances indicate that there may be an other-than-temporary decline in value. We consider various factors to determine if a decrease in the value of the investment is other-than-temporary. The Company did not recognize any other-than-temporary decrease in the value of its other investments in unconsolidated joint ventures or partnerships during the years ended December 31, 2014, 2013, and 2012.
	Combined summary financial information relating to all of the unconsolidated joint ventures and partnerships operations (not just our proportionate share), is presented below for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	As of and For the Year Ended		UDR/MetLife I			UDR/MetLife II				UDR/MetLife Vitruvian Park®				Texas				UDR/KFH				Other joint ventures			Total
	31-Dec-14
	Condensed Statements of Operations:
	Total revenues		$	727		$	152,047			$	19,376			$	—			$	19,724			$	1,579		$	193,453
	Property operating expenses		618			52,150				10,711				—				7,498				1,122			72,099
	Real estate depreciation and amortization		2,130			41,504				7,380				—				14,426				3,959			69,399
	Operating income/(loss)		(2,021		)	58,393				1,285				—				(2,200		)		(3,502		)	51,955
	Interest expense		—			(48,493		)		(4,131		)		—				(5,873		)		(94		)	(58,591		)
	Other income/(expense)		—			—				—				—				—				—			—
	Gain/(loss) on sale of real estate		—			—				—				—				—				—			—
	Income/(loss) from discontinued operations		(31,802		)	—				—				(4,229		)		—				—			(36,031		)
	Net income/(loss)		$	(33,823	)	$	9,900			$	(2,846	)		$	(4,229	)		$	(8,073	)		$	(3,596	)	$	(42,667	)
	UDR recorded income (loss) from unconsolidated entities		$	(2,955	)	$	2,814			$	(4,068	)		$	(772	)		$	(2,601	)		$	576		$	(7,006	)
	Condensed Balance Sheets:
	Total real estate, net		$	89,482		$	1,986,237			$	278,600			$	—			$	235,623			$	351,861		$	2,941,803
	Assets held for sale		1,978			—				—				214,218				—				—			216,196
	Cash and cash equivalents		1,983			15,245				6,570				—				2,507				6,239			32,544
	Other assets		(146		)	19,589				3,933				—				1,128				4,203			28,707
	Total assets		93,297			2,021,071				289,103				214,218				239,258				362,303			3,219,250
	Amount due/(from) to UDR		107			(444		)		1,960				—				531				843			2,997
	Third party debt		—			1,147,109				123,649				—				165,209				68,510			1,504,477
	Liabilities held for sale		5,110			—				—				224,596				—				—			229,706
Accounts payable and accrued liabilities		749			17,573				6,766				—				1,396				17,851			44,335
Total liabilities		5,966			1,164,238				132,375				224,596				167,136				87,204			1,781,515
Total equity		$	87,331		$	856,833			$	156,728			$	(10,378	)		$	72,122			$	275,099		$	1,437,735
UDR’s investment in unconsolidated joint ventures		$	13,306		$	431,277			$	80,302			$	(25,901	)		$	21,596			$	197,646		$	718,226
As of and For the Year Ended		UDR/MetLife I			UDR/MetLife II				UDR/MetLife Vitruvian Park®				Texas				UDR/KFH				Other joint ventures			Total
31-Dec-13
Condensed Statements of Operations:
Total revenues		$	691		$	109,926			$	7,680			$	—			$	19,221			$	5,324		$	142,842
Property operating expenses		621			33,809				4,633				—				7,035				3,292			49,390
Real estate depreciation and amortization		115			30,122				3,830				—				14,199				3,564			51,830
Operating income/(loss)		(45		)	45,995				(783		)		—				(2,013		)		(1,532		)	41,622
Interest expense		—			(37,055		)		(1,886		)		—				(5,872		)		(913		)	(45,726		)
Other income/(expense)		—			1				—				—				—				—			1
Income/(loss) from discontinued operations		(22,388		)	—				—				(9,584		)		—				—			(31,972		)
Net income/(loss)		$	(22,433	)	$	8,941			$	(2,669	)		$	(9,584	)		$	(7,885	)		$	(2,445	)	$	(36,075	)
UDR recorded income/(loss) from unconsolidated entities		$	(4,675	)	$	4,471			$	(2,851	)		$	(1,218	)		$	(2,366	)		$	6,224		$	(415	)
Condensed Balance Sheets:
Total real estate, net		$	90,971		$	1,476,588			$	283,878			$	—			$	249,097			$	65,133		$	2,165,667
Assets held for sale		753,427			—				—				231,981				—				—			985,408
Cash and cash equivalents		305			16,454				3,498				—				2,289				—			22,546
Other assets		4,782			16,666				1,578				—				1,474				83			24,583
Total assets		849,485			1,509,708				288,954				231,981				252,860				65,216			3,198,204
Amount due to UDR		4,520			2,275				1,352				—				420				1,136			9,703
Third party debt		—			877,799				120,999				—				165,209				—			1,164,007
Liabilities held for sale		346,810			—				—				230,393				—				—			577,203
Accounts payable and accrued liabilities		89			14,508				7,152				—				1,234				2,813			25,796
Total liabilities		351,419			894,582				129,503				230,393				166,863				3,949			1,776,709
Total equity		$	498,066		$	615,126			$	159,451			$	1,588			$	85,997			$	61,267		$	1,421,495
UDR’s investment in unconsolidated joint ventures		$	47,497		$	327,926			$	79,318			$	(23,591	)		$	25,919			$	50,586		$	507,655
For the Year Ended December 31, 2012		UDR/MetLife I			UDR/MetLife II				UDR/MetLife Vitruvian Park®				Texas				UDR/KFH				Other joint ventures			Total
Condensed Statements of Operations:
Total revenues		$	632		$	87,386			$	—			$	—			$	18,670			$	2,724		$	109,412
Property operating expenses		252			25,737				—				—				6,831				1,368			34,188
Real estate depreciation and amortization		124			32,553				—				—				16,546				1,897			51,120
Operating income/(loss)		256			29,096				—				—				(4,707		)		(541		)	24,104
Interest expense		—			(29,170		)		—				—				(5,890		)		(561		)	(35,621		)
Other income/(expense)		—			(9		)		—				—				—				—			(9		)
Income/(loss) from discontinued operations		8,609			—				—				(1,040		)		—				—			7,569
Net income/(loss)		$	8,865		$	(83	)		$	—			$	(1,040	)		$	(10,597	)		$	(1,102	)	$	(3,957	)
UDR recorded income/(loss) from unconsolidated entities		$	(1,750	)	$	15			$	—			$	(2,399	)		$	(3,221	)		$	(1,224	)	$	(8,579	)

Secured_Debt_and_Unsecured_Deb

Secured Debt and Unsecured Debt	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
SECURED DEBT AND UNSECURED DEBT	SECURED AND UNSECURED DEBT
	The following is a summary of our secured and unsecured debt at December 31, 2014 and 2013 (dollars in thousands):
		Principal Outstanding						For the Year Ended December 31, 2014
								Weighted Average			Weighted Average		Number of Communities
		December 31,						Interest Rate			Years to Maturity		Encumbered
		2014			2013
	Secured Debt:
	Fixed Rate Debt
	Mortgage notes payable (a)	$	401,210		$	445,706		5.46	%		1.6		6
	Fannie Mae credit facilities (b)	568,086			626,667			5.12	%		4		22
	Total fixed rate secured debt	969,296			1,072,373			5.26	%		3		28
	Variable Rate Debt
	Mortgage notes payable	31,337			63,595			1.94	%		2.1		1
	Tax-exempt secured notes payable (c)	94,700			94,700			0.83	%		8.2		2
	Fannie Mae credit facilities (b)	266,196			211,409			1.6	%		5.2		7
	Total variable rate secured debt	392,233			369,704			1.44	%		5.7		10
	Total Secured Debt	1,361,529			1,442,077			4.16	%		3.8		38
	Unsecured Debt:
	Commercial Banks
	Borrowings outstanding under an unsecured credit facility due December 2017 (d) (h)	152,500			—			1.09	%		2.9
	Senior Unsecured Notes
	5.13% Medium-Term Notes due January 2014 (e)	—			184,000			—	%		—
	5.50% Medium-Term Notes due April 2014 (net of discount of $20) (e)	—			128,480			—	%		—
	5.25% Medium-Term Notes due January 2015 (net of discounts of $6 and $134, respectively) (f)	325,169			325,041			5.25	%		—
	5.25% Medium-Term Notes due January 2016	83,260			83,260			5.25	%		1
	4.25% Medium-Term Notes due June 2018 (net of discounts of $1,465 and $1,893, respectively) (h)	298,535			298,107			4.25	%		3.4
	2.17% Term Notes due June 2018 (h)	215,000			250,000			2.17	%		3.4
	1.53% Term Notes due June 2018 (h)	100,000			65,000			1.53	%		3.4
	1.31% Term Notes due June 2018 (h)	35,000			35,000			1.31	%		3.4
	3.70% Medium-Term Notes due October 2020 (net of discounts of $46 and $54, respectively) (h)	299,954			299,946			3.7	%		5.8
	4.63% Medium-Term Notes due January 2022 (net of discounts of $2,523 and $2,882, respectively) (h)	397,477			397,118			4.63	%		7
	3.75% Medium-Term Notes due July 2024 (net of discount of $990) (g) (h)	299,010			—			3.75	%		9.5
	8.50% Debentures due September 2024	15,644			15,644			8.5	%		9.7
	Other	27			30			N/A			N/A
	Total Unsecured Debt	2,221,576			2,081,626			3.81	%		4.6
	Total Debt	$	3,583,105		$	3,523,703		3.94	%		4.3
	Our secured debt instruments generally feature either monthly interest and principal or monthly interest-only payments with balloon payments due at maturity. For purposes of classification of the above table, variable rate debt with a derivative financial instrument designated as a cash flow hedge is deemed as fixed rate debt due to the Company having effectively established a fixed interest rate for the underlying debt instrument. As of December 31, 2014, secured debt encumbered $2.2 billion or 26.6% of UDR’s total real estate owned based upon gross book value ($6.2 billion or 73.4% of UDR’s real estate owned based on gross book value is unencumbered).
	(a) At December 31, 2014, fixed rate mortgage notes payable are generally due in monthly installments of principal and interest and mature at various dates from December 2015 through May 2019 and carry interest rates ranging from 3.43% to 5.94%.
	The Company will from time to time acquire properties subject to fixed rate debt instruments. In those situations, management will record the secured debt at its estimated fair value and amortize any difference between the fair value and par to interest expense over the life of the underlying debt instrument. During the years ended December 31, 2014, 2013, and 2012, the Company had $5.1 million, $5.1 million, and $4.9 million, respectively, of amortization expense on the fair market adjustment of debt assumed in acquisition of properties, which was included in Interest expense on the Consolidated Statements of Operations. The unamortized fair market adjustment was a net premium of $6.7 million and $11.8 million at December 31, 2014 and 2013, respectively.
	(b) UDR has three secured credit facilities with Fannie Mae with an aggregate commitment of $834.3 million at December 31, 2014. The Fannie Mae credit facilities are for terms of seven to ten years (maturing at various dates from May 2017 through July 2023) and bear interest at floating and fixed rates. At December 31, 2014, we have $568.1 million of the outstanding balance is fixed at a weighted average interest rate of 5.12% and the remaining balance of $266.2 million on these facilities is currently at a weighted average variable interest rate of 1.60%.
	Further information related to these credit facilities is as follows (dollars in thousands):
		December 31, 2014			31-Dec-13
	Borrowings outstanding	$	834,282		$	838,076
	Weighted average borrowings during the period ended	835,873			839,597
	Maximum daily borrowings during the period ended	837,564			841,494
	Weighted average interest rate during the period ended	4.1		%	4.2		%
	Weighted average interest rate at the end of the period	4		%	4.1		%
	(c) The variable rate mortgage notes payable that secure tax-exempt housing bond issues mature on August 2019 and March 2032. Interest on these notes is payable in monthly installments. The variable mortgage notes have interest rates of 0.78% and 0.93%, respectively, as of December 31, 2014.
	(d) The Company has a $900 million unsecured revolving credit facility with a maturity date to December 2017, a six month extension option, and an accordion feature that allows the Company to increase the facility to $1.45 billion. Based on the Company's current credit rating, the credit facility carries an interest rate equal to LIBOR plus a spread of 100 basis points and a facility fee of 15 basis points. As of December 31, 2014, the Company had a balance of $152.5 million outstanding under the revolving credit facility.
	The following is a summary of short-term bank borrowings under UDR’s bank credit facility at December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Total revolving credit facility	$	900,000		$	900,000
	Borrowings outstanding at end of period (1)	152,500			—
	Weighted average daily borrowings during the period ended	291,761			169,844
	Maximum daily borrowings during the period ended	625,000			372,000
	Weighted average interest rate during the period ended	1.2		%	1.2		%
	Interest rate at end of the period	1.1		%	1.3		%
	(1) Excludes $1.9 million and $2.2 million of letters of credit at December 31, 2014 and 2013, respectively.
	(e) Paid off at maturity with borrowings under the Company’s $900 million unsecured revolving credit facility.
	(f)	In January 2015, we paid off $325.2 million of 5.25% medium-term notes due January 2015 with borrowings under the Company’s $900 million unsecured revolving credit facility.
	(g) In June 2014, the Company issued $300 million of 3.750% senior unsecured medium-term notes due July 1, 2024. Interest is payable semi-annually beginning on January 1, 2015. These notes were issued at 99.652% of the principal amount and had a discount of $1.0 million at December 31, 2014. The Company used the net proceeds to pay down borrowings outstanding on our $900 million unsecured credit facility and for general corporate purposes.
	(h) The Operating Partnership is a guarantor at December 31, 2014 and 2013.
	The aggregate maturities, including amortizing principal payments of secured debt, of total debt for the next five years subsequent to December 31, 2014 are as follows (dollars in thousands):
	Year		Secured Fixed Rate Debt			Secured Variable Rate Debt			Total Secured Debt			Total Unsecured Debt (a)		Total Debt
2015		$	196,648		$	—		$	196,648		$	324,286	$	520,934
2016		135,167			31,337			166,504			82,377		248,881
2017		177,774			65,000			242,774			152,500		395,274
2018		120,969			104,787			225,756			648,443		874,199
2019		248,738			67,700			316,438			—		316,438
Thereafter		90,000			123,409			213,409			1,013,970		1,227,379
Total		$	969,296		$	392,233		$	1,361,529		$	2,221,576	$	3,583,105
(a) With the exception of the 1.31% Term Notes due June 2018 and revolving credit facility which carry a variable interest rate, all unsecured debt carries fixed interest rates.
We were in compliance with the covenants of our debt instruments at December 31, 2014.

IncomeLoss_Per_Share_Notes

Income/(Loss) Per Share (Notes)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Share [Text Block]	INCOME/(LOSS) PER SHARE
	The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data):
		Year Ended December 31,
		2014				2013			2012
	Numerator for income/(loss) per share:
	Income/(loss) from continuing operations	$	16,260			$	2,340		$	(46,305	)
	Gain/(loss) on sale of real estate owned, net of tax	143,572				—			—
	(Income)/loss from continuing operations attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)		48			2,089
	(Income)/loss from continuing operations attributable to noncontrolling interests	3				60			(140		)
	Income/(loss) from continuing operations attributable to UDR, Inc.	154,324				2,448			(44,356		)
	Distributions to preferred stockholders - Series E (Convertible)	(3,724		)		(3,724		)	(3,724		)
	Distributions to preferred stockholders - Series G	—				—			(2,286		)
	Premium on preferred stock redemption or repurchases, net	—				—			(2,791		)
	Income/(loss) from continuing operations attributable to common stockholders	$	150,600			$	(1,276	)	$	(53,157	)
	Income/(loss) from discontinued operations, net of tax	$	10			$	43,942		$	266,608
	(Income)/loss from discontinued operations attributable to redeemable noncontrolling interests in the Operating Partnership	—				(1,578		)	(10,075		)
	Income/(loss) from discontinued operations attributable to common stockholders	$	10			$	42,364		$	256,533
	Net income/(loss) attributable to common stockholders	$	150,610			$	41,088		$	203,376
	Denominator for income/(loss) per share - basic and diluted:
	Weighted average common shares outstanding	252,707				250,684			239,482
	Non-vested restricted stock awards	(1,179		)		(715		)	(631		)
	Denominator for income/(loss) per share - basic	251,528				249,969			238,851
	Incremental shares issuable from assumed conversion of:	1,917				—			—
	Stock options and unvested resticted stock
	Denominator for income/(loss) per share - diluted	253,445				249,969			238,851
	Income/(loss) per weighted average common share - basic:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.6			$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.6			$	0.16		$	0.85
	Income/(loss) per weighted average common share - diluted:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.59			$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.59			$	0.16		$	0.85
	Basic income/(loss) per common share is computed based upon the weighted average number of common shares outstanding. Diluted income/(loss) per share is computed based upon the common shares issuable from the assumed conversion of the OP Units, convertible preferred stock, stock options, and restricted stock. Only those instruments having a dilutive impact on our basic income/(loss) per share are included in diluted income/(loss) per share during the periods.
	During the years ended December 31, 2013 and 2012, the effect of the conversion of the OP Units, convertible preferred stock, stock options and restricted stock is not dilutive, and is therefore not included in the above calculations as the Company reported a loss from continuing operations attributable to common stockholders.
	The following table sets forth the additional shares of common stock outstanding by equity instrument if converted to common stock for each of the years ended December 31, 2014, 2013, and 2012 (shares in thousands):
		Year Ended December 31,
		2014			2013			2012
	OP Units	9,247			9,337			9,411
	Preferred Stock	3,036			3,036			3,036
	Stock options and unvested restricted stock	1,917			1,584			1,361

Stockholders_Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2014
Stockholders' Equity Attributable to Parent [Abstract]
STOCKHOLDERSb EQUITY	STOCKHOLDERS’ EQUITY
	UDR has an effective registration statement that allows the Company to sell an undetermined number of debt and equity securities as defined in the prospectus. The Company has the ability to issue 350,000,000 shares of common stock and 50,000,000 shares of preferred shares as of December 31, 2014.
	The company has an equity distribution agreement which allows it from time to time, through its sales agents, to offer and sell up to 20,000,000 shares of its common stock. Sales of such shares will be made by means of ordinary brokers’ transactions on the NYSE at market prices. As of December 31, 2014, 16,518,567 shares were available for sale under the continuous equity program.
	During the year ended December 31, 2014, the Company entered into the following equity transactions for our common stock:
	•	Sold 3,410,433 shares of common stock through the Company’s equity distribution agreement at a weighted average price per share of $29.95, for aggregate gross proceeds of approximately $102.1 million;
	•	Issued 860,811 shares of common stock through the Company’s 1999 Long-Term Incentive Plan (the “LTIP”), net of forfeitures of 12,199; and
	•	Converted 153,451 OP Units into Company common stock.
	In 2015, through February 24, 2015, we sold 3,432,936 shares of common stock through the Company’s equity distribution agreement at a weighted average price per share of $32.28, for aggregate gross proceeds of approximately $110.8 million.
	Distributions are subject to the approval of the Board of Directors and are dependent upon our strategy, financial condition and operating results. UDR’s common distributions for the years ended December 31, 2014, 2013, and 2012 totaled $1.04, $0.94, and $0.88 per share, respectively. For taxable years ending on or before December 31, 2014, the Internal Revenue Service (“IRS”) allowed REITs to distribute up to 90% of total distributions in common shares with the residual distributed in cash as a means of enhancing liquidity.
	Preferred Stock
	The Series E Cumulative Convertible Preferred Stock (“Series E”) has no stated par value and a liquidation preference of $16.61 per share. Subject to certain adjustments and conditions, each share of the Series E is convertible at any time and from time to time at the holder’s option into one share of our common stock prior to a “Special Dividend” declared in 2008 (1.083 shares after the Special Dividend). The holders of the Series E are entitled to vote on an as-converted basis as a single class in combination with the holders of common stock at any meeting of our stockholders for the election of directors or for any other purpose on which the holders of common stock are entitled to vote. The Series E has no stated maturity and is not subject to any sinking fund or any mandatory redemption.
	Distributions declared on the Series E for the years ended December 31, 2014, 2013, and 2012 were $1.33 per share. The Series E is not listed on any exchange. At December 31, 2014 and 2013, a total of 2,803,812 shares of the Series E were outstanding.
	UDR is authorized to issue up to 20,000,000 shares of the Series F Preferred Stock (“Series F”). The Series F may be purchased by holders of UDR’s operating partnership units, or OP Units, at a purchase price of $0.0001 per share. OP Unitholders are entitled to subscribe for and purchase one share of UDR’s Series F for each OP Unit held. At December 31, 2014 and 2013, a total of 2,464,183 shares of the Series F were outstanding with an aggregate purchase value of $246. Holders of the Series F are entitled to one vote for each share of the Series F they hold, voting together with the holders of our common stock, on each matter submitted to a vote of security holders at a meeting of our stockholders. The Series F does not entitle its holders to any other rights, privileges or preferences.
	In May 2007, UDR issued 5,400,000 shares of the 6.75% Series G Cumulative Redeemable Preferred Stock (“Series G”). On May 31, 2012, the Company completed the redemption of all outstanding shares of its Series G. A total of 3,264,362 shares of the Series G was redeemed at a redemption price of $25 per share in cash, plus accrued and unpaid dividends to the redemption date for a total cost of $82.1 million. As a result of this redemption, the write off of additional paid in capital of $2.8 million related to the issuance of the Series G is recognized as a decrease to our net income/(loss) attributable to common stockholders.
	Distributions declared on the Series G for the years ended December 31, 2014, 2013, and 2012 were $0.00, $0.00 and $0.57 per share, respectively. At December 31, 2014 and 2013, there were no shares of the Series G outstanding.
	Distribution Reinvestment and Stock Purchase Plan
	UDR’s Distribution Reinvestment and Stock Purchase Plan (the “Stock Purchase Plan”) allows common and preferred stockholders the opportunity to purchase, through the reinvestment of cash dividends, additional shares of UDR’s common stock. From inception through December 31, 2008, shareholders have elected to utilize the Stock Purchase Plan to reinvest their distribution for the equivalent of 9,957,233 shares of Company common stock. Shares in the amount of 10,963,730 were reserved for issuance under the Stock Purchase Plan as of December 31, 2014. During the year ended December 31, 2014, UDR acquired all shares issued through the open market.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS
	In May 2001, the stockholders of UDR approved the long term incentive plan (“LTIP”), which supersedes the 1985 Stock Option Plan. The LTIP authorizes the granting of awards which may take the form of options to purchase shares of common stock, stock appreciation rights, restricted stock, dividend equivalents, other stock-based awards, and any other right or interest relating to common stock or cash incentive awards to Company directors, employees and outside trustees to promote the success of the Company by linking individual’s compensation via grants of share based payment. During the year ended December 31, 2014, the stockholders of UDR voted to amend and restate the LTIP to increase the number of shares reserved from 16,000,000 shares to 19,000,000 shares on an unadjusted basis for issuance upon the grant or exercise of awards under the LTIP. As of December 31, 2014, there were 10,067,371 common shares available for issuance under the LTIP.
	The LTIP contains change of control provisions allowing for the immediate vesting of an award upon certain events such as a merger where UDR is not the surviving entity. Upon the death or disability of an award recipient all outstanding instruments will vest and all restrictions will lapse. Unless otherwise specified in the agreement, upon the retirement of an award recipient, all outstanding instruments will vest and all restrictions will lapse. The LTIP specifies that in the event of a capital transaction, which includes but is not limited to stock dividends, stock splits, extraordinary cash dividends and spin-offs, the number of shares available for grant in totality or to a single individual is to be adjusted proportionately. The LTIP specifies that when a capital transaction occurs that would dilute the holder of the stock award, prior grants are to be adjusted such that the recipient is no worse as a result of the capital transaction.
	A summary of UDR’s stock option and restricted stock activities during the year ended December 31, 2014 is as follows:
		Option Outstanding				Option Exercisable				Restricted Stock
		Number of		Weighted		Number of		Weighted		Number		Weighted
		Options		Average		Options		Average		of shares		Average Fair
				Exercise				Exercise				Value Per
				Price				Price				Restricted Stock
	Balance, December 31, 2013	2,430,127		$	12.63	2,430,127		$	12.63	758,745		$	23.89
	Granted	—		—		—		—		873,010		23.14
	Exercised	(164,285	)	10.06		(164,285	)	10.06		—		—
	Vested	—		—		—		—		(619,578	)	22.7
	Forfeited	—		—		—		—		(12,199	)	23.74
	Balance, December 31, 2014	2,265,842		$	12.82	2,265,842		$	12.82	999,978		$	23.98
	As of December 31, 2014, the Company had issued 4,517,514 shares of restricted stock under the LTIP.
	Stock Option Plan
	UDR has granted stock options to our employees, subject to certain conditions. Each stock option is exercisable into one common share.
	There is no remaining compensation cost related to unvested stock options as of December 31, 2014.
	During the year ended December 31, 2014, stock options with a fair value of $4.8 million were exercised.
	The weighted average remaining contractual life on all options outstanding as of December 31, 2014 is 3.4 years. 1,830,672 of share options had exercise prices at $10.06; 404,291 of share options had exercise prices at $24.38; and 30,879 of share options had exercise prices at $25.10.
	During the years ended December 31, 2014, 2013, and 2012, respectively, we recognized $0.0, $0.0, and $95,000 of net compensation expense related to outstanding stock options.
	Restricted Stock Awards
	Restricted stock awards are granted to Company employees, officers, and directors. The restricted stock awards are valued based upon the closing sales price of UDR common stock on the date of grant. Compensation expense is recorded under the straight-line method over the vesting period, which is generally three to four years. Restricted stock awards earn dividends payable in cash. Some of the restricted stock grants are based on the Company’s performance and are subject to adjustment during the initial one year performance period. For the years ended December 31, 2014, 2013, and 2012, we recognized $4.2 million, $3.6 million, and $3.7 million of compensation expense related to the amortization of restricted stock awards, respectively. The total remaining compensation cost on unvested restricted stock awards was $2.5 million and had a weighted average remaining contractual life of 1.1 years as of December 31, 2014.
	Long-Term Incentive Compensation
	In February 2014, certain officers of the Company were awarded a restricted stock grant under the 2014 Long-Term Incentive Program (“2014 LTI”). Fifty percent of the 2014 LTI award is based upon FFO as Adjusted and fifty percent is based on Total Shareholder Return (“TSR”) as measured relative to comparable apartment REITs. The actual amount that vests was determined in February 2015 based upon the actual achievement of the metrics. Each award vests pro rata over three years commencing with the establishment of the award and continuing for two years following determination of the amount of the award at the end of the annual performance period. The portion of the restricted stock grant based upon FFO as Adjusted was valued based upon the closing sales price of UDR common stock on the date of grant. The portion of the restricted stock grant based upon TSR was valued at $21.15 per share on the grant date as determined by a lattice-binomial option-pricing model based on a Monte Carlo simulation using a volatility factor of 23.8%.
	In February 2013, certain officers of the Company were awarded a restricted stock grant under the 2013 Long-Term Incentive Program (“2013 LTI”). Fifty percent of the 2013 LTI award is based upon FFO and fifty percent is based on Total Shareholder Return (“TSR”) as measured relative to comparable apartment REITs. The actual amount that vests was determined in February 2014 based upon the actual achievement of the metrics. Each award vests pro rata over three years commencing with the establishment of the award and continuing for two years following determination of the amount of the award at the end of the annual performance period. The portion of the restricted stock grant based upon FFO was valued based upon the closing sales price of UDR common stock on the date of grant. The portion of the restricted stock grant based upon TSR was valued at $21.97 per share on the grant date as determined by a lattice-binomial option-pricing model based on a Monte Carlo simulation using a volatility factor of 15.8%.
	Compensation expense is recorded under the accelerated method over the vesting period for the 2014 LTI and 2013 LTI. For the year ended December 31, 2014 and 2013, we recognized $9.8 million and $5.9 million, respectively, of compensation expense related to the amortization of the awards. The total remaining compensation cost on unvested 2014 LTI and 2013 LTI awards was $5.8 million and had a weighted average remaining contractual life of 1.8 years as of December 31, 2014.
	During 2010, certain officers of the Company were awarded a restricted stock grant under the 2010-2012 Long-Term Incentive Program (“2010-2012 LTI”). The actual amount of the awards that vested in 2012 was determined based upon the Company’s achievement of the specified performance metrics during the three-year performance period. The grants were valued on the grant date based upon the market price of UDR common stock on the date of grant. Compensation expense was recorded pro rata over the three-year performance period. For the year ended December 31, 2012, we recognized $4.9 million of compensation expense related to the amortization of the awards.
	Profit Sharing Plan
	Our profit sharing plan (the “Plan”) is a defined contribution plan covering all eligible full-time employees. Under the Plan, UDR makes discretionary profit sharing and matching contributions to the Plan as determined by the Compensation Committee of the Board of Directors. Aggregate provisions for contributions, both matching and discretionary, which are included in UDR’s Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012, was $854,000, $919,000, and $631,000, respectively.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES
	For 2014, 2013, and 2012, UDR believes that we have complied with the REIT requirements specified in the Code. As such, the REIT would generally not be subject to federal income taxes.
	For income tax purposes, distributions paid to common stockholders may consist of ordinary income, qualified dividends, capital gains, unrecaptured section 1250 gains, return of capital, or a combination thereof. Distributions that exceed our current and accumulated earnings and profits constitute a return of capital rather than taxable income and reduce the stockholder’s basis in their common shares. To the extent that a distribution exceeds both current and accumulated earnings and profits and the stockholder’s basis in the common shares, it generally will be treated as a gain from the sale or exchange of that stockholder’s common shares. Taxable distributions paid per common share were taxable as follows for the years ended December 31, 2014, 2013, and 2012:
		Year Ended December 31,
		2014			2013			2012
	Ordinary income	$	0.695		$	0.744		$	0.174
	Qualified ordinary income	0.139			—			—
	Long-term capital gain	0.105			0.114			0.186
	Unrecaptured section 1250 gain	0.076			0.067			0.515
	Total	$	1.015		$	0.925		$	0.875
	We have a TRS that is subject to federal and state income taxes. A TRS is a C-corporation which has not elected REIT status and as such is subject to United States federal and state income tax. The components of the provision for income taxes are as follows for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Income tax (benefit)/expense
	Current
	Federal	$	147		$	(1,030	)	$	1,961
	State	550			846			1,463
	Total current	697			(184		)	3,424
	Deferred
	Federal	20,138			(6,907		)	(21,479		)
	State	5,159			(1,190		)	(3,021		)
	Total deferred	25,297			(8,097		)	(24,500		)
	Total income tax (benefit)/expense	$	25,994		$	(8,281	)	$	(21,076	)
	Classification of income tax (benefit)/expense
	Continuing operations	$	(15,098	)	$	(7,299	)	$	(30,717	)
	Gain/(loss) on sale of real estate owned	41,087			—			—
	Discontinued operations	5			(982		)	9,641
	Deferred income taxes are provided for the change in temporary differences between the basis of certain assets and liabilities for financial reporting purposes and income tax reporting purposes. The expected future tax rates are based upon enacted tax laws. The components of our TRS deferred tax assets and liabilities are as follows for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Deferred tax assets:
	Federal and state tax attributes	$	—		$	13,069		$	1,464
	Book/tax depreciation	6,692			19,354			12,345
	Construction capitalization differences	75			—			6,635
	Investment in partnerships	—			—			3,112
	Debt and interest deductions	—			10,311			—
	Other	401			—			2,009
	Total deferred tax assets	7,168			42,734			25,565
	Valuation allowance	—			(1,310		)	(1,390		)
	Net deferred tax assets	7,168			41,424			24,175
	Deferred tax liabilities:
	Construction capitalization differences	—			(3,766		)	—
	Investment in partnerships	—			(5,080		)	—
	Other	(192		)	(305		)	—
	Total deferred tax liabilities	(192		)	(9,151		)	—
	Net deferred tax asset	$	6,976		$	32,273		$	24,175
	Income tax benefit/(expense), net differed from the amounts computed by applying the U.S. statutory rate of 35% to pretax income/(loss) for the years ended December 31, 2014, 2013, and 2012 as follows (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Income tax (benefit)/expense
	U.S. federal income tax (benefit)/expense	$	28,819		$	(8,493	)	$	21,853
	State income tax provision	2,678			46			2,497
	Other items	(137		)	246			(1,682		)
	Conversion of certain TRS entities to REITs	(5,770		)	—			—
	Valuation allowance	404			(80		)	(43,744		)
	Total income tax (benefit)/expense	$	25,994		$	(8,281	)	$	(21,076	)
	As of December 31, 2014, the Company, through our TRS, had federal net operating loss carryovers (“NOL”) of $19.5 million expiring in 2032 through 2033. As of December 31, 2014, the TRS had state NOLs of approximately $57.8 million expiring in 2020 through 2031. Prior to the conversion adjustment, as of December 31, 2014, the Company had a valuation allowance of $1.7 million against its state NOL. During the year ended December 31, 2014, the Company had a net change of $400,000 in the valuation allowance. These attributes are still available to the new REITs, but are carried at a zero effective tax rate.
	For the year ended December 31, 2014, the Tax benefit/(provision), net increased $7.8 million as compared to 2013. The increase was primarily a result of the Company recognizing a one-time tax benefit of $5.8 million in 2014 related to the conversion of certain taxable REIT subsidiary entities into REITs. Additionally, Gain/(loss) on sale of real estate owned, net of tax included approximately $41.1 million of tax.
	GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The financial statements reflect expected future tax consequences of income tax positions presuming the taxing authorities’ full knowledge of the tax position and all relevant facts, but without considering time values. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition.
	The Company evaluates our tax position using a two-step process. First, we determine whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The Company will then determine the amount of benefit to recognize and record the amount of the benefit that is more likely than not to be realized upon ultimate settlement. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in income tax expense. As of December 31, 2014 and 2013, UDR has no material unrecognized income tax benefits/(provisions).
	The Company files income tax returns in federal and various state and local jurisdictions. With few exceptions, the Company is no longer subject to federal, state and local income tax examination by tax authorities for years prior to 2010. The tax years 2010 through 2013 remain open to examination by the major taxing jurisdictions to which the Company is subject.

Noncontrolling_Interests

Noncontrolling Interests	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Abstract]
NONCONTROLLING INTERESTS	NONCONTROLLING INTERESTS
	Redeemable Noncontrolling Interests in the Operating Partnership
	Interests in the Operating Partnership held by limited partners are represented by OP Units. The income is allocated to holders of OP Units based upon net income attributable to common stockholders and the weighted average number of OP Units outstanding to total common shares plus OP Units outstanding during the period. Capital contributions, distributions, and profits and losses are allocated to noncontrolling interests in accordance with the terms of the individual partnership agreements.
	Limited partners have the right to require the Operating Partnership to redeem all or a portion of the OP Units held by the limited partner at a redemption price equal to and in the form of the Cash Amount as defined in the Amended and Restated Agreement of Limited Partnership of the Operating Partnership (the “Operating Partnership Agreement”), provided that such OP Units have been outstanding for at least one year. UDR, as the general partner of the Operating Partnership may, in its sole discretion, purchase the OP Units by paying to the limited partner either the Cash Amount or the REIT Share Amount (generally one share of common stock of the Company for each OP Unit), as defined in the Operating Partnership Agreement. Accordingly, the Company records the OP Units outside of permanent equity and reports the OP Units at their redemption value using the Company’s stock price at each balance sheet date.
	The following table sets forth redeemable noncontrolling interests in the Operating Partnership for the years ended December 31, 2014 and 2013 (dollars in thousands):
		Year Ended December 31,
		2014			2013
	Redeemable noncontrolling interests in the Operating Partnership, beginning of year	$	217,597		$	223,418
	Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership	73,954			3,656
	Conversion of OP Units to Common Stock	(4,372		)	(1,817		)
	Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership	5,511			1,530
	Distributions to redeemable noncontrolling interests in the Operating Partnership	(10,077		)	(9,440		)
	Allocation of other comprehensive income/(loss)	(133		)	250
	Redeemable noncontrolling interests in the Operating Partnership, end of year	$	282,480		$	217,597
	The following sets forth net income/(loss) attributable to common stockholders and transfers from redeemable noncontrolling interests in the Operating Partnership for the following periods (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Net income/(loss) attributable to common stockholders	$	150,610		$	41,088		$	203,376
	Conversion of OP units to UDR Common Stock	4,372			1,817			529
	Change in equity from net income/(loss) attributable to common stockholders and conversion of OP units to UDR Common Stock	$	154,982		$	42,905		$	203,905
	Noncontrolling Interests
	Noncontrolling interests represent interests of unrelated partners in certain consolidated affiliates, and is presented as part of equity in the Consolidated Balance Sheets since these interests are not redeemable. During the years ended December 31, 2014, 2013, and 2012, net (income)/loss attributable to noncontrolling interests was $3,000, $60,000, and $(140,000), respectively.
	During the year ended December 31, 2012, the Company acquired all of the noncontrolling interests in two consolidated affiliates for $4.9 million, one of which owns a 434 apartment home community for $4.0 million and the other is a development project for $900,000. See the “Consolidated Joint Ventures” section of Note 5, Unconsolidated Joint Ventures and Partnerships, for additional information on the consolidated development joint venture.

Fair_Value_of_Derivatives_and_

Fair Value of Derivatives and Financial Instruments	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS	FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS
	Fair value is based on the price that would be received to sell an asset or the exit price that would be paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three-level valuation hierarchy prioritizes observable and unobservable inputs used to measure fair value. The fair value hierarchy consists of three broad levels, which are described below:
	•	Level 1 — Quoted prices in active markets for identical assets or liabilities that the entity has the ability to access.
	•	Level 2 — Observable inputs other than prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated with observable market data.
	•	Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.
	The estimated fair values of the Company’s financial instruments either recorded or disclosed on a recurring basis as of December 31, 2014 and 2013 are summarized as follows (dollars in thousands):
						Fair Value at December 31, 2014, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2014		Fair Value Estimate at December 31, 2014		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs
						Assets or		Inputs		(Level 3)
						Liabilities		(Level 2)
						(Level 1)
	Description:
	Notes receivable (a)	$	14,369	$	14,808	$	—	$	—	$	14,808
	Derivatives - Interest rate contracts (b)	88		88		—		88		—
	Total assets	$	14,457	$	14,896	$	—	$	88	$	14,808
	Derivatives - Interest rate contracts (b)	$	10,368	$	10,368	$	—	$	10,368	$	—
	Secured debt instruments - fixed rate: (c)
	Mortgage notes payable	401,210		415,663		—		—		415,663
	Fannie Mae credit facilities	568,086		606,623		—		—		606,623
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	31,337		31,337		—		—		31,337
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	266,196		266,196		—		—		266,196
	Unsecured debt instruments (c):
	Commercial banks	152,500		152,500		—		—		152,500
	Senior unsecured notes	2,069,076		2,144,125		—		—		2,144,125
	Total liabilities	$	3,593,473	$	3,721,512	$	—	$	10,368	$	3,711,144
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	282,480	$	282,480	$	—	$	282,480	$	—
						Fair Value at December 31, 2013, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2013		Fair Value Estimate at December 31, 2013		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs (Level 3)
						Assets or		Inputs (Level 2)
						Liabilities (Level 1)
	Description:
	Notes receivable (a)	$	83,033	$	83,833	$	—	$	—	83,833
	Total assets	$	83,033	$	83,833	$	—	$	—	$	83,833
	Derivatives- Interest rate contracts (b)	$	4,965	$	4,965	$	—	$	4,965	$	—
	Secured debt instruments- fixed rate: (c)
	Mortgage notes payable	445,706		466,375		—		—		466,375
	Fannie Mae credit facilities	626,667		661,094		—		—		661,094
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	63,595		63,595		—		—		63,595
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	211,409		211,409		—		—		211,409
	Unsecured debt instruments: (c)
	Senior unsecured notes	2,081,626		2,149,003		—		—		2,149,003
	Total liabilities	$	3,528,668	$	3,651,141	$	—	$	4,965	$	3,646,176
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	217,597	$	217,597	$	—	$	217,597	$	—
	(a)	See Note 2, Significant Accounting Policies.
	(b)	See Note 13, Derivatives and Hedging Activity.
	(c)	See Note 6, Secured Debt and Unsecured Debt.
	(d)	See Note 11, Noncontrolling Interests.
	There were no transfers into or out of each of the levels of the fair value hierarchy.
	Financial Instruments Carried at Fair Value
	The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The fair values of interest rate options are determined using the market standard methodology of discounting the future expected cash receipts that would occur if variable interest rates rise above the strike rate of the caps. The variable interest rates used in the calculation of projected receipts on the cap are based on an expectation of future interest rates derived from observable market interest rate curves and volatilities.
	The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees.
	Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. However, as of December 31, 2014 and 2013, the Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. In conjunction with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio.
	Redeemable noncontrolling interests in the Operating Partnership have a redemption feature and are marked to their redemption value. The redemption value is based on the fair value of the Company’s common stock at the redemption date, and therefore, is calculated based on the fair value of the Company’s common stock at the balance sheet date. Since the valuation is based on observable inputs such as quoted prices for similar instruments in active markets, redeemable noncontrolling interests in the Operating Partnership are classified as Level 2.
	Financial Instruments Not Carried at Fair Value
	At December 31, 2014, the fair values of cash and cash equivalents, restricted cash, accounts receivable, prepaids, real estate taxes payable, accrued interest payable, security deposits and prepaid rent, distributions payable and accounts payable approximated their carrying values because of the short term nature of these instruments. The estimated fair values of other financial instruments were determined by the Company using available market information and appropriate valuation methodologies. Considerable judgment is necessary to interpret market data and develop estimated fair values. Accordingly, the estimates presented herein are not necessarily indicative of the amounts the Company would realize on the disposition of the financial instruments. The use of different market assumptions or estimation methodologies may have a material effect on the estimated fair value amounts.
	We estimate the fair value of our notes receivable and debt instruments by discounting the remaining cash flows of the debt instrument at a discount rate equal to the replacement market credit spread plus the corresponding treasury yields. Factors considered in determining a replacement market credit spread include general market conditions, borrower specific credit spreads, time remaining to maturity, loan-to-value ratios and collateral quality, where applicable (Level 3).
We record impairment losses on long-lived assets used in operations when events and circumstances indicate that the assets might be impaired and the undiscounted cash flows estimated to be generated by the future operation and disposition of those assets are less than the net book value of those assets. Our cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. The net book value of impaired assets is reduced to fair value. Our estimates of fair value represent our best estimate based upon Level 3 inputs such as industry trends and reference to market rates and transactions.
We consider various factors to determine if a decrease in the value of our investment in and advances to unconsolidated joint ventures, net is other-than-temporary. These factors include, but are not limited to, age of the venture, our intent and ability to retain our investment in the entity, the financial condition and long-term prospects of the entity, and the relationships with the other joint venture partners and its lenders. Based on the significance of the unobservable inputs, we classify these fair value measurements within Level 3 of the valuation hierarchy. The Company did not incur any other-than-temporary decrease in the value of its investments in unconsolidated joint ventures during the years ended December 31, 2014, 2013, and 2012.
After determining an other-than-temporary decrease in the value of an equity method investment has occurred, we estimate the fair value of our investment by estimating the proceeds we would receive upon a hypothetical liquidation of the investment at the date of measurement. Inputs reflect management’s best estimate of what market participants would use in pricing the investment giving consideration to the terms of the joint venture agreement and the estimated discounted future cash flows to be generated from the underlying joint venture assets. The inputs and assumptions utilized to estimate the future cash flows of the underlying assets are based upon the Company’s evaluation of the economy, market trends, operating results, and other factors, including judgments regarding costs to complete any construction activities, lease up and occupancy rates, rental rates, inflation rates, capitalization rates utilized to estimate the projected cash flows at the disposition, and discount rates.

Derivatives_and_Hedging_Activi

Derivatives and Hedging Activity	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVES AND HEDGING ACTIVITY	DERIVATIVES AND HEDGING ACTIVITY
	Risk Management Objective of Using Derivatives
	The Company is exposed to certain risks arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk primarily by managing the amount, sources, and duration of its debt funding and through the use of derivative financial instruments. Specifically, the Company may enter into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s investments and borrowings.
	Cash Flow Hedges of Interest Rate Risk
	The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company primarily uses interest rate swaps and caps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Interest rate caps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty if interest rates rise above the strike rate on the contract in exchange for an up front premium.
	The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in Accumulated other comprehensive income/(loss), net in the Consolidated Balance Sheets and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. During the years ended December 31, 2014, 2013, and 2012, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt and forecasted issuances of fixed-rate debt. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings. During the year ended December 31, 2014 the Company recorded a gain of approximately $3,000 from ineffectiveness in earnings attributable to a timing mismatch between the derivative and the hedged item. During the years ended December 31, 2013, and 2012, the Company recorded less than $1,000 of loss from ineffectiveness in earnings attributable to reset date and index mismatches between the derivative and the hedged item, and interest rate swaps with a fair value other than zero at inception of the hedging relationship.
	Amounts reported in Accumulated other comprehensive income/(loss), net in the Consolidated Balance Sheets relate to derivatives that will be reclassified to interest expense as interest payments are made on the Company’s variable-rate debt. Through December 31, 2015, the Company estimates that an additional $5.0 million will be reclassified as an increase to interest expense.
	As of December 31, 2014, the Company had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk (dollars in thousands):
	Interest Rate Derivative		Number of Instruments		Notional
	Interest rate swaps		14		$	365,000
	Interest rate caps		3		$	243,079
	Derivatives not designated as hedges are not speculative and are used to manage the Company’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings and resulted in a gain/(loss) of $(4,000), $271,000, and $290,000 for the years ended December 31, 2014, 2013, and 2012, respectively.
	As of December 31, 2014, the Company had the following outstanding derivatives that were not designated as hedges in qualifying hedging relationships (dollars in thousands):
	Product		Number of Instruments		Notional
	Interest rate caps		1		$	96,409
	Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet
	The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2014 and 2013 (dollars in thousands):
		Asset Derivatives								Liability Derivatives
		(included in Other assets)								(included in Other liabilities)
		Fair Value at:								Fair Value at:
		December 31,				December 31,				December 31,				December 31,
		2014				2013				2014				2013
	Derivatives designated as hedging instruments:
	Interest rate products	$	86			$	—			$	10,368			$	4,965
	Derivatives not designated as hedging instruments:
	Interest rate products	$	2			$	—			$	—			$	—
	Tabular Disclosure of the Effect of Derivative Instruments on the Consolidated Statements of Operations
	The tables below present the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	Derivatives in Cash Flow Hedging Relationships		Unrealized holding gain/(loss) Recognized in OCI												Gain/(Loss) Reclassified from Accumulated OCI into									Gain/(Loss) Recognized in Interest expense
			(Effective Portion)												Interest expense									(Ineffective Portion and Amount Excluded from Effectiveness Testing)
															(Effective Portion)
			Year ended December 31,												Year ended December 31,									Year ended December 31,
			2014				2013				2012				2014			2013			2012			2014		2013		2012
	Interest rate products		$	(8,695	)		$	(469	)		$	(4,924	)		$	(4,834	)	$	(6,851	)	$	(7,649	)	$	3	$	—	$	—
			Gain/(Loss) Recognized in
			Interest and other income/(expense), net
			Year ended December 31,
	Derivatives Not Designated as Hedging Instruments		2014				2013				2012
	Interest rate products		$	(4	)		$	271			$	290
	Credit-risk-related Contingent Features
	The Company has agreements with some of its derivative counterparties that contain a provision where (1) if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then the Company could also be declared in default on its derivative obligations; or (2) the Company could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the Company’s default on the indebtedness.
	Certain of the Company’s agreements with its derivative counterparties contain provisions where if there is a change in the Company’s financial condition that materially changes the Company’s creditworthiness in an adverse manner, the Company may be required to fully collateralize its obligations under the derivative instrument. At December 31, 2014 and 2013, no cash collateral was posted or required to be posted by the Company or by a counterparty.
	The Company also has an agreement with a derivative counterparty that incorporates the loan and financial covenant provisions of the Company’s indebtedness with a lender affiliate of the derivative counterparty. Failure to comply with these covenant provisions would result in the Company being in default on any derivative instrument obligations covered by the agreement.
	The Company has certain agreements with some of its derivative counterparties that contain a provision where, in the event of default by the Company or the counterparty, the right of setoff may be exercised. Any amount payable to one party by the other party may be reduced by its setoff against any amounts payable by the other party. Events that give rise to default by either party may include, but are not limited to, the failure to pay or deliver payment under the derivative contract, the failure to comply with or perform under the derivative agreement, bankruptcy, a merger without assumption of the derivative agreement, or in a merger, a surviving entity's creditworthiness is materially weaker than the original party to the derivative agreement.
	As of December 31, 2014, the fair value of derivatives in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements was $10.6 million. If the Company had breached any of these provisions at December 31, 2014, it would have been required to settle its obligations under the agreements at their termination value of $10.6 million.
	The Company has elected not to offset derivative positions in the consolidated financial statements. The tables below present the effect on its financial position had the Company made the election to offset its derivative positions as of December 31, 2014 and December 31, 2013 (dollars in thousands):
	Offsetting of Derivative Assets
			Gross Amounts of Recognized Assets				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets						Net Amount
															Financial Instruments			Cash Collateral Received
	December 31, 2014		$	88			$	—			$	88			$	(27	)	$	—		$	61
	December 31, 2013		$	—			$	—			$	—			$	—		$	—		$	—
	(a) Amounts reconcile to the aggregate fair value of derivative assets in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.
	Offsetting of Derivative Liabilities
			Gross Amounts of Recognized Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Liabilities Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets						Net Amount
															Financial Instruments			Cash Collateral Posted
	December 31, 2014		$	10,368			$	—			$	10,368			$	(27	)	$	—		$	10,341
	December 31, 2013		$	4,965			$	—			$	4,965			$	—		$	—		$	4,965
	(a) Amounts reconcile to the aggregate fair value of derivative liabilities in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES
	Commitments
	Real Estate Under Development
	The following summarizes the Company’s real estate commitments at December 31, 2014 (dollars in thousands):
		Number of		Costs Incurred				Expected Costs			Average Ownership
		Properties		to Date (a)				to Complete (unaudited)			Stake
	Wholly-owned — under development	1		$	177,632		(b)	$	40,068		100	%
	Wholly-owned — redevelopment	1		83,778			(b)	14,222			100	%
	Joint ventures:
	Unconsolidated joint ventures	3		225,013				172,155		(c)	Various
	Participating loan investments	1		62,707			(d)	29,302		(e)	0	%
	Total			$	549,130			$	255,747
	(a) Represents 100% of project costs incurred to date.
	(b) Costs incurred to date include $14.7 million and $1.8 million of accrued fixed assets for development and redevelopment, respectively.
	(c) Represents UDR’s contributed and remaining equity commitment in unconsolidated joint ventures.
	(d) Represents the participating loan balance funded as of December 31, 2014.
	(e) Represents UDR’s remaining participating loan commitment for Steele Creek.
	Ground and Other Leases
	UDR owns six communities which are subject to ground leases expiring between 2019 and 2103. In addition, UDR is a lessee to various operating leases related to office space rented by the Company with expiration dates through 2016. Future minimum lease payments as of December 31, 2014 are as follows (dollars in thousands):
		Ground				Office Space
		Leases (a)
	2015	$	5,412			$	709
	2016	5,412				124
	2017	5,412				76
	2018	5,412				76
	2019	5,412				76
	Thereafter	313,735				109
	Total	$	340,795			$	1,170
	(a)	For purposes of our ground lease contracts, the Company uses the minimum lease payment, if stated in the agreement. For ground lease agreements where there is a reset provision based on the communities appraised value or consumer price index but does not include a specified minimum lease payment, the Company uses the current rent over the remainder of the lease term.
	UDR incurred $5.4 million, $5.2 million, $5.1 million of ground rent expense for the years ended December 31, 2014, 2013, and 2012, respectively. These costs are reported within the line item Other Operating Expenses on the Consolidated Statements of Operations. The Company incurred $1.3 million, $1.3 million, $1.1 million of rent expense related to office space for the years ended December 31, 2014, 2013, and 2012, respectively. These costs are included in General and Administrative on the Consolidated Statements of Operations. In February 2015, the Company acquired the office building in Highlands Ranch, Colorado, which housed its corporate offices it had previously leased. See Note 4, Real Estate Owned, for additional details.
	Contingencies
	Litigation and Legal Matters
	The Company is subject to various legal proceedings and claims arising in the ordinary course of business. The Company cannot determine the ultimate liability with respect to such legal proceedings and claims at this time. The Company believes that such liability, to the extent not provided for through insurance or otherwise, will not have a material adverse effect on our financial condition, results of operations or cash flow.

Reportable_Segments

Reportable Segments	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
REPORTABLE SEGMENTS	REPORTABLE SEGMENTS
	GAAP guidance requires that segment disclosures present the measure(s) used by the chief operating decision maker to decide how to allocate resources and for purposes of assessing such segments’ performance. UDR’s chief operating decision maker is comprised of several members of its executive management team who use several generally accepted industry financial measures to assess the performance of the business for our reportable operating segments.
	UDR owns and operates multifamily apartment communities that generate rental and other property related income through the leasing of apartment homes to a diverse base of tenants. The primary financial measures for UDR’s apartment communities are rental income and NOI. Rental income represents gross market rent less adjustments for concessions, vacancy loss and bad debt. NOI is defined as rental income less direct property rental expenses. Rental expenses include real estate taxes, insurance, personnel, utilities, repairs and maintenance, administrative and marketing. Excluded from NOI is property management expense which is calculated as 2.75% of property revenue to cover the regional supervision and accounting costs related to consolidated property operations, and land rent. UDR’s chief operating decision maker utilizes NOI as the key measure of segment profit or loss.
	UDR’s two reportable segments are Same-Store Communities and Non-Mature Communities/Other:
	•	Same-Store Communities represent those communities acquired, developed, and stabilized prior to January 1, 2013 and held as of December 31, 2014. A comparison of operating results from the prior year is meaningful as these communities were owned and had stabilized occupancy and operating expenses as of the beginning of the prior year, there is no plan to conduct substantial redevelopment activities, and the community is not held for disposition within the current year. A community is considered to have stabilized occupancy once it achieves 90% occupancy for at least three consecutive months.
	•	Non-Mature Communities/Other represent those communities that do not meet the criteria to be included in Same-Store Communities, including, but not limited to, recently acquired, developed and redeveloped communities, and the non-apartment components of mixed use properties.
	Management evaluates the performance of each of our apartment communities on a Same-Store Community and Non-Mature Community/Other basis, as well as individually and geographically. This is consistent with the aggregation criteria under GAAP as each of our apartment communities generally has similar economic characteristics, facilities, services, and tenants. Therefore, the Company’s reportable segments have been aggregated by geography in a manner identical to that which is provided to the chief operating decision maker.
	All revenues are from external customers and no single tenant or related group of tenants contributed 10% or more of UDR’s total revenues during the years ended December 31, 2014, 2013, and 2012.
	The following table details rental income and NOI from continuing and discontinued operations for UDR’s reportable segments for the years ended December 31, 2014, 2013, and 2012, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. in the Consolidated Statements of Operations (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Reportable apartment home segment rental income
	Same-Store Communities
	West Region	$	245,803		$	231,156		$	218,268
	Mid-Atlantic Region	161,566			160,208			155,777
	Southeast Region	107,991			102,988			97,699
	Northeast Region	60,796			58,075			54,461
	Southwest Region	54,810			52,302			46,800
	Non-Mature Communities/Other	174,183			150,907			171,239
	Total segment and consolidated rental income	$	805,149		$	755,636		$	744,244
	Reportable apartment home segment NOI
	Same-Store Communities
	West Region	$	178,926		$	166,033		$	154,205
	Mid-Atlantic Region	111,762			111,643			108,490
	Southeast Region	71,528			67,264			63,122
	Northeast Region	44,897			42,350			39,377
	Southwest Region	33,725			31,927			27,878
	Non-Mature Communities/Other	115,483			94,824			111,128
	Total segment and consolidated NOI	556,321			514,041			504,200
	Reconciling items:
	Joint venture management and other fees	13,044			12,442			11,911
	Property management	(22,142		)	(20,780		)	(20,465		)
	Other operating expenses	(8,271		)	(7,136		)	(5,718		)
	Real estate depreciation and amortization	(358,154		)	(341,490		)	(350,401		)
	General and administrative	(47,800		)	(42,238		)	(43,792		)
	Casualty-related recoveries/(charges), net	(541		)	12,253			(8,495		)
	Other depreciation and amortization	(5,775		)	(6,741		)	(4,105		)
	Income/(loss) from unconsolidated entities	(7,006		)	(415		)	(8,579		)
	Interest expense	(130,454		)	(126,083		)	(138,792		)
	Interest and other income/(expense), net	11,837			4,681			2,703
	Tax benefit/(provision), net	15,136			7,299			30,282
	Gain/(loss) on sale of real estate owned, net of tax	143,647			40,449			251,554
	Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)	(1,530		)	(7,986		)
	Net (income)/loss attributable to noncontrolling interests	3			60			(140		)
	Net income/(loss) attributable to UDR, Inc.	$	154,334		$	44,812		$	212,177
	The following table details the assets of UDR’s reportable segments as of December 31, 2014 and 2013 (dollars in thousands):
		December 31,			December 31,
		2014			2013
	Reportable apartment home segment assets:
	Same-Store communities:
	West Region	$	2,358,444		$	2,337,980
	Mid-Atlantic Region	1,410,156			1,395,772
	Southeast Region	786,438			785,134
	Northeast Region	746,550			738,805
	Southwest Region	440,721			434,875
	Non-mature Communities/Other	2,640,950			2,515,411
	Total segment assets	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Total segment assets — net book value	5,948,487			5,999,183
	Reconciling items:
	Cash and cash equivalents	15,224			30,249
	Restricted cash	22,340			22,796
	Deferred financing costs, net	22,686			26,924
	Notes receivable, net	14,369			83,033
Investment in and advances to unconsolidated joint ventures, net	718,226			507,655
Other assets	105,202			137,882
Total consolidated assets	$	6,846,534		$	6,807,722
Capital expenditures related to our Same-Store Communities totaled $55.3 million, $47.5 million, and $46.4 million for the years ended December 31, 2014, 2013, and 2012, respectively. Capital expenditures related to our Non-Mature Communities/Other totaled $8.1 million, $8.3 million, and $8.7 million for the years ended December 31, 2014, 2013, and 2012, respectively.
Markets included in the above geographic segments are as follows:
i.	West Region — Orange County, San Francisco, Seattle, Monterey Peninsula, Los Angeles, Other Southern California, and Portland
ii.	Mid-Atlantic Region — Metropolitan D.C., Baltimore, Richmond, Norfolk, and Other Mid-Atlantic
iii.	Southeast Region — Tampa, Orlando, Nashville, and Other Florida
iv.	Northeast Region — New York and Boston
v.	Southwest Region — Dallas and Austin

Hurricane_Related_Charges

Hurricane Related Charges	12 Months Ended
	Dec. 31, 2014
Hurricane Related Charges [Abstract]
Hurricane Related Charges	-RELATED (RECOVERIES)/CHARGES
	In October 2012, Hurricane Sandy hit the East Coast, affecting three of the Company’s operating communities (1,706 apartment homes) located in New York City. The properties suffered some physical damage, and were closed to residents for a period following the hurricane. The Company has insurance policies that provide coverage for property damage and business interruption, subject to applicable retention.
	Based on the claims filed and management’s estimates, the Company recognized a $9.0 million impairment charge for the damaged assets’ net book value and incurred $10.4 million of repair and cleanup costs during the year ended December 31, 2012. The impairment charge and the repair and cleanup costs incurred were reduced as of December 31, 2012 by $14.5 million of estimated insurance recovery, and were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations. During the year ended December 31, 2013, no material adjustments to the impairment charge and the repair and cleanup costs incurred were recognized. With the exception of one of the properties that is under redevelopment at December 31, 2013, the rehabilitation of the remaining two properties was substantially completed as of December 31, 2013 and was completed during 2014.
	As of December 31, 2013, the Company had settled the Hurricane Sandy claims and received insurance proceeds in excess of the $14.5 million estimated insurance recovery receivable related to the impairment charge and the repair and cleanup costs incurred. As a result, the Company recognized a Casualty-related recovery of approximately $4.8 million and a casualty gain of approximately $654,000 for the year ended December 31, 2013. Both the recovery and casualty gain were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations.
	Based on the claims filed and management’s estimates, the Company recognized $4.4 million of business interruption losses for the year ended December 31, 2012, of which $3.6 million were related to rent concession rebates provided to residents during the period the properties were uninhabitable and were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations, and $767,000 were related to rent that was not contractually receivable and were classified as a reduction to Rental income on the Consolidated Statements of Operations. As noted below, the Company recovered from the insurance carrier approximately $4.2 million of the $4.4 million of 2012 business interruption losses. The Company estimates that it incurred an additional $3.4 million of business interruption losses for the year ended December 31, 2013. As noted below, the Company recovered from the insurance carrier approximately $2.6 million of the $3.4 million of 2013 business interruption losses.
	During the year ended December 31, 2013, the Company received approximately $6.8 million of insurance proceeds for recovery of business interruption losses. Of the $6.8 million of insurance proceeds received in 2013, $4.2 million related to recovery of business interruption losses incurred in 2012 and the remaining $2.6 million related to recovery of business interruption losses incurred in 2013. The $6.8 million of recovery was classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations as of December 31, 2013.
	During the year ended December 31, 2014, the Company recorded $541,000 of casualty-related losses due to property damage incurred during an earthquake and a storm in California, all of which are included in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations.

Unaudited_Summarized_Consolida

Unaudited Summarized Consolidated Quarterly Financial Data	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
UNAUDITED SUMMARIZED CONSOLIDATED QUARTERLY FINANCIAL DATA	UNAUDITED SUMMARIZED CONSOLIDATED QUARTERLY FINANCIAL DATA
	Selected consolidated quarterly financial data for the three and twelve months ended December 31, 2014 and 2013 is summarized in the table below (dollars in thousands, except per share amounts):
		Three Months Ended
		March 31,			June 30,		September 30,		December 31,
	2014
	Rental income (a)	$	194,352		$	200,959	$	203,587	$	206,104
	Income/(loss) from continuing operations	(5,195		)	4,359		10,611		6,485
	Income/(loss) from discontinued operations, net of tax	(87		)	18		79		—
	Net income/(loss) attributable to common stockholders	17,430			29,076		39,618		64,486
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	0.07		$	0.12	$	0.16	$	0.25
	Weighted average number of shares outstanding
	Basic	250,177			250,255		251,655		253,983
	Diluted	251,822			252,191		253,732		256,000
	2013
	Rental income (a)	$	181,961		$	186,285	$	187,917	$	190,321
	Income/(loss) from continuing operations	(1,162		)	4,525		2,351		(3,374		)
	Income/(loss) from discontinued operations, net of tax	853			829		884		41,376
	Net income/(loss) attributable to common stockholders	(1,199		)	4,261		2,257		35,769
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	(0.00	)	$	0.02	$	0.01	$	0.14
	Weighted average number of shares outstanding
	Basic	249,917			249,985		249,985		249,987
	Diluted	249,917			251,406		251,454		249,987
	(a)	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
	(b)	Quarterly income/(loss) per share amounts may not total to the annual amounts.

Consolidation_and_Basis_of_Pre1

Consolidation and Basis of Presentation (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
CONSOLIDATION AND BASIS OF PRESENTATION	CONSOLIDATION AND BASIS OF PRESENTATION
	Organization and Formation
	UDR, Inc. (“UDR,” the “Company,” “we,” or “our”) is a self-administered real estate investment trust, or REIT, that owns, operates, acquires, renovates, develops, redevelops, and manages apartment communities generally in high barrier-to-entry markets located in the United States. The high barrier-to-entry markets are characterized by limited land for new construction, difficult and lengthy entitlement process, expensive single-family home prices and significant employment growth potential. At December 31, 2014, our consolidated apartment portfolio consisted of 139 consolidated communities located in 20 markets consisting of 39,851 apartment homes. In addition, the Company has an ownership interest in 10,055 apartment homes through unconsolidated joint ventures.
	Basis of Presentation
	The accompanying consolidated financial statements of UDR include its wholly-owned and/or controlled subsidiaries (see the “Consolidated Joint Ventures” section of Note 5, Joint Ventures and Partnerships, for further discussion). All significant intercompany accounts and transactions have been eliminated in consolidation. Certain previously reported amounts have been reclassified to conform to the current financial statement presentation.
	The accompanying consolidated financial statements include the accounts of UDR and its subsidiaries, including United Dominion Realty, L.P. (the “Operating Partnership” or the “OP”). As of December 31, 2014 and 2013, there were 183,278,698 units in the Operating Partnership outstanding, of which 174,113,225 or 95.0% and 173,959,774 or 94.9%, respectively, were owned by UDR and 9,165,473 or 5.0% and 9,318,924 or 5.1%, respectively, were owned by limited partners. The consolidated financial statements of UDR include the noncontrolling interests of the unitholders in the Operating Partnership.
	The Company evaluated subsequent events through the date its financial statements were issued. No significant recognized or non-recognized subsequent events were noted other than those mentioned in Note 5, Joint Ventures and Partnerships, and Note 8, Stockholders’ Equity.
United Dominion Reality L.P.
Entity Information [Line Items]
CONSOLIDATION AND BASIS OF PRESENTATION	CONSOLIDATION AND BASIS OF PRESENTATION
	United Dominion Realty, L.P. (“UDR, L.P.,” the “Operating Partnership,” “we” or “our”) is a Delaware limited partnership that owns, acquires, renovates, redevelops, manages, and disposes of multifamily apartment communities generally located in high barrier to entry markets located in the United States. The high barrier to entry markets are characterized by limited land for new construction, difficult and lengthy entitlement process, expensive single-family home prices and significant employment growth potential. UDR, L.P. is a subsidiary of UDR, Inc. (“UDR” or the “General Partner”), a self-administered real estate investment trust, or REIT, through which UDR conducts a significant portion of its business. During the years ended December 31, 2014, 2013, and 2012, rental revenues of the Operating Partnership represented 52%, 54%, 54%, respectively, of the General Partner’s consolidated rental revenues (including those classified within discontinued operations). At December 31, 2014, the Operating Partnership’s apartment portfolio consisted of 68 communities located in 17 markets consisting of 20,814 apartment homes.
	Interests in UDR, L.P. are represented by operating partnership units (“OP Units”). The Operating Partnership’s net income is allocated to the partners, which is initially based on their respective distributions made during the year and secondly, their percentage interests. Distributions are made in accordance with the terms of the Amended and Restated Agreement of Limited Partnership of United Dominion Realty, L.P. (the “Operating Partnership Agreement”), on a per unit basis that is generally equal to the dividend per share on UDR’s common stock, which is publicly traded on the New York Stock Exchange (“NYSE”) under the ticker symbol “UDR.”
	As of December 31, 2014, there were 183,278,698 OP Units outstanding, of which 174,113,225 or 95.0% were owned by UDR and affiliated entities and 9,165,473 or 5.0% were owned by non-affiliated limited partners. There were 183,278,698 OP Units in the Operating Partnership outstanding as of December 31, 2013, of which 173,959,774 or 94.9% were owned by UDR and affiliated entities and 9,318,924 or 5.1% were owned by non-affiliated limited partners.
	As sole general partner of the Operating Partnership, UDR owned 110,883 general partnership interest units or 0.06% of the total OP Units outstanding as of December 31, 2014 and 2013. At December 31, 2014 and 2013, there were 183,167,815 OP Units outstanding, of which 1,873,332 were Class A Limited Partnership OP Units. UDR owned 174,002,342 or 95.0% and 173,848,891 or 94.9% at December 31, 2014 and 2013, respectively. The remaining 9,165,473 or 5.0% and 9,318,924 or 5.1% OP Units outstanding of limited partnership interest were held by non-affiliated partners at December 31, 2014 and 2013, respectively, of which 1,751,671 were Class A Limited Partnership units. See Note 9, Capital Structure.
	The Operating Partnership evaluated subsequent events through the date its financial statements were issued. No recognized or non-recognized subsequent events were noted.

Significant_Accounting_Policie1

Significant Accounting Policies (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
SIGNIFICANT ACCOUNTING POLICIES	SIGNIFICANT ACCOUNTING POLICIES
	Recent Accounting Pronouncements
	In April 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, which incorporates a requirement that a disposition represent a strategic shift in an entity’s operations into the definition of a discontinued operation. In accordance with the ASU, a discontinued operation represents (1) a component of an entity or group of components that has been disposed of or is classified as held for sale in a single transaction and represents a strategic shift that has or will have a major effect on an entity’s financial results, or (2) an acquired business that is classified as held for sale on the date of acquisition. A strategic shift could include a disposal of (1) a separate major line of business, (2) a separate major geographic area of operations, (3) a major equity method investment, or (4) other major parts of an entity. The standard requires prospective application and will be effective for interim and annual periods beginning on or after December 15, 2014, with early adoption permitted. The early adoption provision excludes components of an entity that were sold or classified as held for sale prior to the adoption of the standard.
	The Company elected to early adopt this standard effective January 1, 2014, which had a significant impact on the Company’s consolidated financial statements as further discussed in Note 3, Discontinued Operations. Subsequent to the Company’s adoption of ASU 2014-08, the sale of real estate that does not meet the definition of a discontinued operation under the standard is included in Gain/(loss) on sale of real estate owned, net of tax on the Consolidated Statements of Operations.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The updated standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The standard specifically excludes lease contracts. The ASU allows for the use of either the full or modified retrospective transition method, and the standard will be effective for the Company on January 1, 2017; early adoption is not permitted. The Company has not yet selected a transition method and we are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures.
	Real Estate
	Real estate assets held for investment are carried at historical cost and consist of land, buildings and improvements, furniture, fixtures and equipment and other costs incurred during their development, acquisition and redevelopment.
	Expenditures for ordinary repair and maintenance costs are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to the acquisition and/or improvement of real estate assets are capitalized and depreciated over their estimated useful lives if the expenditures qualify as a betterment or the life of the related asset will be substantially extended beyond the original life expectancy.
	UDR purchases real estate investment properties and records the tangible and identifiable intangible assets and liabilities acquired based on their estimated fair value. The primary, although not only, identifiable intangible asset associated with our portfolio is the value of existing lease agreements. When recording the acquisition of a community, we first assign fair value to the estimated intangible value of the existing lease agreements and then to the estimated value of the land, building and fixtures assuming the community is vacant. The Company estimates the intangible value of the lease agreements by determining the lost revenue associated with a hypothetical lease-up. Depreciation on the building is based on the expected useful life of the asset and the in-place leases are amortized over their remaining average contractual life. Property acquisition costs are expensed as incurred.
	Quarterly or when changes in circumstances warrant, UDR will assess our real estate properties for indicators of impairment. In determining whether the Company has indicators of impairment in our real estate assets, we assess whether the long-lived asset’s carrying value exceeds the community’s undiscounted future cash flows, which is representative of projected net operating income (“NOI”) plus the residual value of the community. Our future cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. If such indicators of impairment are present and the carrying value exceeds the undiscounted cash flows of the community, an impairment loss is recognized equal to the excess of the carrying amount of the asset over its estimated fair value. Our estimates of fair market value represent our best estimate based primarily upon unobservable inputs related to rental rates, operating costs, growth rates, discount rates, capitalization rates, industry trends and reference to market rates and transactions.
	For long-lived assets to be disposed of, impairment losses are recognized when the fair value of the asset less estimated cost to sell is less than the carrying value of the asset. Properties classified as real estate held for sale generally represent properties that are actively marketed or contracted for sale with the closing expected to occur within the next twelve months. Real estate held for sale is carried at the lower of cost, net of accumulated depreciation, or fair value, less the cost to sell, determined on an asset-by-asset basis. Expenditures for ordinary repair and maintenance costs on held for sale properties are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to held for sale properties are capitalized at cost. Depreciation is not recorded on real estate held for sale.
	Depreciation is computed on a straight-line basis over the estimated useful lives of the related assets which are 35 to 55 years for buildings, 10 to 35 years for major improvements, and 3 to 10 years for furniture, fixtures, equipment, and other assets.
	Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation. The Company capitalizes costs directly related to the predevelopment, development, and redevelopment of a capital project, which include, but are not limited to, interest, real estate taxes, insurance, and allocated development and redevelopment overhead related to support costs for personnel working on the capital projects. We use our professional judgment in determining whether such costs meet the criteria for capitalization or must be expensed as incurred. These costs are capitalized only during the period in which activities necessary to ready an asset for its intended use are in progress and such costs are incremental and identifiable to a specific activity to get the asset ready for its intended use. These costs, excluding the direct costs of development and redevelopment and capitalized interest, for the years ended December 31, 2014, 2013, and 2012 were $9.0 million, $11.1 million and $10.0 million, respectively. During the years ended December 31, 2014, 2013, and 2012, total interest capitalized was $20.2 million, $29.4 million, and $26.4 million, respectively. As each home in a capital project is completed and becomes available for lease-up, the Company ceases capitalization on the related portion and depreciation commences over the estimated useful life.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash on hand, demand deposits with financial institutions and short-term, highly liquid investments. We consider all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The majority of the Company’s cash and cash equivalents are held at major commercial banks.
	Restricted Cash
	Restricted cash consists of escrow deposits held by lenders for real estate taxes, insurance and replacement reserves, and security deposits.
	Revenue and Real Estate Sales Gain Recognition
	Rental income related to leases is recognized on an accrual basis when due from residents and tenants in accordance with GAAP. Rental payments are generally due on a monthly basis and recognized when earned. The Company recognizes interest income, management and other fees and incentives when earned, and the amounts are fixed and determinable.
	For sale transactions meeting the requirements for full accrual profit recognition, we remove the related assets and liabilities from our Consolidated Balance Sheets and record the gain or loss in the period the transaction closes. For sale transactions that do not meet the full accrual sale criteria due to our continuing involvement, we evaluate the nature of the continuing involvement and account for the transaction under an alternate method of accounting. Unless certain limited criteria are met, non-monetary transactions, including property exchanges, are accounted for at fair value.
	Sales to entities in which we retain or otherwise own an interest are accounted for as partial sales. If all other requirements for recognizing profit under the full accrual method have been satisfied and no other forms of continuing involvement are present, we recognize profit proportionate to the outside interest in the buyer and defer the gain on the interest we retain. The Company recognizes any deferred gain when the property is sold to a third party. In transactions accounted for by us as partial sales, we determine if the buyer of the majority equity interest in the venture was provided a preference as to cash flows in either an operating or a capital waterfall. If a cash flow preference has been provided, we recognize profit only to the extent that proceeds from the sale of the majority equity interest exceed costs related to the entire property.
	Notes Receivable
	The following table summarizes our notes receivable, net as of December 31, 2014 and 2013 (dollars in thousands):
		Interest rate at December 31, 2014		Balance Outstanding
				December 31, 2014		December 31, 2013
	Note due June 2014 (a)			$	—	$	40,800
	Note due February 2017 (b)	10	%	11,869		14,580
	Note due July 2017 (c)	8	%	2,500		1,400
	Note due June 2022 (net of discount of $0 and $247, respectively) (d)			—		26,253
	Total notes receivable, net			$	14,369	$	83,033
	(a) In the fourth quarter of 2013, in conjunction with the sale of its 95% interest in the Lodge at Stoughton, one of its unconsolidated joint ventures, the Company provided the buyer with a $40.8 million loan secured by the property at LIBOR plus a spread of 350 basis points with two three-month extension options at increased rates and a financing fee. In June 2014, the note was paid in full.
	(b) The Company has a secured note receivable with an unaffiliated third party with an aggregate commitment of $11.9 million, which bears an interest rate of 10.00% per annum. During the year ended December 31, 2014, the Company loaned an additional $1.2 million and received a payment of $3.9 million in the fourth quarter under this note. Interest payments are due monthly. The note matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) the fifth anniversary of the date of the note (February 2017).
	(c) The Company has a secured note receivable with an unaffiliated third party with an aggregate commitment of $2.5 million, which bears an interest rate of 8.00% per annum. During the year ended December 31, 2014, the Company loaned an additional $1.1 million under the note. Interest payments are due monthly. The note matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) the fifth anniversary of the date of the note (July 2017).
	(d) In 2012, the Company purchased a "B" Note secured by a first mortgage on a class A community in West Los Angeles. The $26.5 million loan was purchased at a yield of 7.25% and bore a coupon rate of 7.00%. Interest payments are due monthly and the note is due June 2022. The discount is amortized using the effective interest method. In July 2014, the Company received proceeds of $36.0 million from the repayment of this note, resulting in a net gain of approximately $8.4 million, which is included in Interest and other income/(expense), net on the Consolidated Statements of Operations.
	During the years ended December 31, 2014, 2013 and 2012, the Company recognized $3.4 million, $4.1 million and $2.7 million, respectively, of interest income from these notes receivable, of which $0, $765,000 and $281,000, respectively, were related party interest income. Interest income is included in Interest and other income/(expense), net on the Consolidated Statements of Operations.
	Investment in Joint Ventures and Partnerships
	We use the equity method to account for investments in joint ventures and partnerships that qualify as variable interest entities where we are not the primary beneficiary and entities that we do not control or where we do not own a majority of the economic interest but have the ability to exercise significant influence over the operating and financial policies of the investee. Throughout these financial statements we use the term “joint venture” or “partnership” when referring to investments in entities in which we do not have a 100% ownership interest. The Company also uses the equity method when we function as the managing partner and our venture partner has substantive participating rights or where we can be replaced by our venture partner as managing partner without cause. For a joint venture or partnership accounted for under the equity method, our share of net earnings or losses is reflected as income/loss when earned/incurred and distributions are credited against our investment in the joint venture or partnership as received.
	In determining whether a joint venture or partnership is a variable interest entity, the Company considers: the form of our ownership interest and legal structure; the size of our investment; the financing structure of the entity, including necessity of subordinated debt; estimates of future cash flows; ours and our partner’s ability to participate in the decision making related to acquisitions, disposition, budgeting and financing of the entity; obligation to absorb losses and preferential returns; nature of our partner’s primary operations; and the degree, if any, of disproportionality between the economic and voting interests of the entity. As of December 31, 2014, the Company did not determine any of our joint ventures or partnerships to be variable interest entities.
	We evaluate our investments in unconsolidated joint ventures for events or changes in circumstances that indicate there may be an other-than-temporary decline in value. We consider various factors to determine if a decrease in the value of the investment is other-than-temporary. These factors include, but are not limited to, age of the venture, our intent and ability to retain our investment in the entity, the financial condition and long-term prospects of the entity, the fair value of the property of the joint venture, and the relationships with the other joint venture partners and its lenders. The amount of loss recognized is the excess of the investment’s carrying amount over its estimated fair value. If we believe that the decline in fair value is temporary, no impairment is recorded. The aforementioned factors are taken into consideration as a whole by management in determining the valuation of our equity method investments. Should the actual results differ from management’s judgment, the valuation could be negatively affected and may result in a negative impact to our Consolidated Financial Statements.
	Derivative Financial Instruments
	The Company utilizes derivative financial instruments to manage interest rate risk and generally designates these financial instruments as cash flow hedges. Derivative financial instruments are recorded on our Consolidated Balance Sheets as either an asset or liability and measured quarterly at their fair value. The changes in fair value for cash flow hedges that are deemed effective are reflected in other comprehensive income/(loss) and for non-designated derivative financial instruments in earnings. The ineffective component of cash flow hedges, if any, is recorded in earnings.
	Redeemable Noncontrolling Interests in the Operating Partnership
	Interests in the Operating Partnership held by limited partners are represented by Operating Partnership units (“OP Units”). The income is allocated to holders of OP Units based upon net income available to common stockholders and the weighted average number of OP Units outstanding to total common shares plus OP Units outstanding during the period. Capital contributions, distributions, and profits and losses are allocated to noncontrolling interests in accordance with the terms of the partnership agreement.
	Limited partners have the right to require the Operating Partnership to redeem all or a portion of the OP Units held by the limited partner at a redemption price equal to and in the form of the Cash Amount as defined in the Amended and Restated Agreement of Limited Partnership of the Operating Partnership (the “Operating Partnership Agreement”), provided that such OP Units have been outstanding for at least one year. UDR, as the general partner of the Operating Partnership may, in its sole discretion, purchase the OP Units by paying to the limited partner either the Cash Amount or the REIT Share Amount (generally one share of Common Stock of the Company for each OP Unit), as defined in the Operating Partnership Agreement. Accordingly, the Company records the OP Units outside of permanent equity and reports the OP Units at their redemption value using the Company’s stock price at each balance sheet date.
	Income Taxes
	Due to the structure of the Company as a REIT and the nature of the operations for the operating properties, no provision for federal income taxes has been provided for at UDR. Historically, the Company has generally incurred only state and local excise and franchise taxes. UDR has elected for certain consolidated subsidiaries to be treated as taxable REIT subsidiaries (“TRS”), primarily those engaged in development activities.
	Income taxes for our TRS are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rate is recognized in earnings in the period of the enactment date. The Company’s deferred tax assets are generally the result of differing depreciable lives on capitalized assets and timing of expense recognition for certain accrued liabilities. As of December 31, 2014 and 2013, UDR’s net deferred tax asset of $7.0 million, which had no valuation allowance, and $32.3 million, net of a valuation allowance of $1.3 million, respectively, was included in Other assets on the Consolidated Balance Sheets.
	Prior to 2012, our TRS had a history of losses and, as a result, historically recognized a valuation allowance for net deferred tax assets. Each quarter, the Company evaluates the need to retain all or a portion of the valuation allowance on its net deferred tax assets. In 2012, the Company determined that it was more likely than not that the deferred tax assets, including any remaining net operating loss carry forward, would be realized. In making this determination, the Company analyzed, among other things, its recent history of earnings from sales of depreciable property, forecasts of future earnings and its cumulative earnings for the last twelve quarters. The reversal of the valuation allowance resulted in an income tax benefit of $44.4 million during the year ended December 31, 2012, $21.5 million of which is reported in continuing operations and included within Tax benefit/(provision), net in the Consolidated Statements of Operations, and $22.9 million of which is included within Income/(loss) from discontinued operations, net of tax in the Consolidated Statements of Operations.
	GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition.
	The Company recognizes its tax positions and evaluates them using a two-step process. First, UDR determines whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The Company will determine the amount of benefit to recognize and record the amount that is more likely than not to be realized upon ultimate settlement.
	UDR had no material unrecognized tax benefit, accrued interest or penalties at December 31, 2014. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2010 through 2013 remain open to examination by tax jurisdictions to which we are subject. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in income tax expense.
	Discontinued Operations
	Prior to the adoption of ASU No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, the results of operations for those properties sold during the year or classified as held for sale at the end of the current year are classified as discontinued operations in the current and prior periods. Further, to meet the discontinued operations criteria, the Company will not have any significant continuing involvement in the ownership or operation of the property after the sale or disposition. Once a property is classified as held for sale, depreciation is no longer recorded. However, if the Company determines that the property no longer meets the criteria for held for sale, the Company will recapture any unrecorded depreciation on the property. The assets and liabilities, if any, of properties classified as held for sale are presented separately on the Consolidated Balance Sheets at the lower of their carrying amount or their estimated fair value less the costs to sell the assets. (See Note 3, Discontinued Operations and Assets Held for Sale, for further discussion).
	Stock-Based Employee Compensation Plans
	The Company measures the cost of employee services received in exchange for an award of an equity instrument based on the award’s fair value on the grant date and recognizes the cost over the period during which the employee is required to provide service in exchange for the award, which is generally the vesting period. The fair value for stock options issued by the Company is calculated utilizing the Black-Scholes-Merton formula. For performance based awards, the Company remeasures the fair value each balance sheet date with adjustments made on a cumulative basis until the award is settled and the final compensation is known. The fair value for market based awards issued by the Company is calculated utilizing a Monte Carlo simulation. For further discussion, see Note 9, Employee Benefit Plans.
	Advertising Costs
	All advertising costs are expensed as incurred and reported on the Consolidated Statements of Operations within the line item General and administrative. During the years ended December 31, 2014, 2013, and 2012, total advertising expense was $6.0 million, $5.7 million, and $6.2 million, respectively.
	Cost of Raising Capital
	Costs incurred in connection with the issuance of equity securities are deducted from stockholders’ equity. Costs incurred in connection with the issuance or renewal of debt are recorded based on the terms of the debt issuance or renewal. Accordingly, if the terms of the renewed or modified debt instrument are deemed to be substantially different (i.e. a 10 percent or greater difference in the cash flows between instruments), all unamortized financing costs associated with the extinguished debt are charged to earnings in the current period and certain costs of new debt issuances are capitalized and amortized over the term of the debt. When the cash flows are not substantially different, the lender costs associated with the renewal or modification are capitalized and amortized into interest expense over the remaining term of the related debt instrument and other related costs are expensed. The balance of any unamortized financing costs associated with retired debt is expensed upon retirement. Deferred financing costs for new debt instruments include fees and costs incurred by the Company to obtain financing. Deferred financing costs are generally amortized on a straight-line basis, which approximates the effective interest method, over a period not to exceed the term of the related debt.
	Preferred Share Redemption and Repurchases
	During the year ended December 31, 2012, the Company completed the redemption of all outstanding shares of its 6.75% Series G Cumulative Redeemable Preferred Stock. A total of 3,264,362 shares of the Series G Preferred Stock was redeemed at a redemption price of $25 per share in cash, plus accrued and unpaid dividends to the redemption date for a total cost of $82.1 million.
	When redeeming or repurchasing preferred stock, the Company recognizes share issuance costs as a charge to the preferred stock on a pro rata basis to the total costs incurred for the preferred stock as well as any premium or discount on the redemption or repurchase. In connection with the redemption of the Series G Preferred Stock, the Company recognized a (decrease)/increase in net income/(loss) attributable to common stockholders of $(2.8) million for the year ended December 31, 2012, which is reported in Premium on preferred stock redemption or repurchases, net on the Consolidated Statements of Operations.
	Comprehensive Income/(Loss)
	Comprehensive income/(loss), which is defined as the change in equity during each period from transactions and other events and circumstances from nonowner sources, including all changes in equity during a period except for those resulting from investments by or distributions to stockholders, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the years ended December 31, 2014, 2013, and 2012, the Company's other comprehensive income/(loss) consisted of the gain/(loss) (effective portion) on derivative instruments that are designated as and qualify as cash flow hedges, (gain)/loss on derivative instruments and marketable securities reclassified from other comprehensive income/(loss) into earnings, and the allocation of other comprehensive income/(loss) to redeemable noncontrolling interests. The (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) is included in interest expense in the accompanying Consolidated Statements of Operations. See Note 13, Derivatives and Hedging Activity, for further discussion. The (gain)/loss on marketable securities reclassified from other comprehensive income/(loss) is included in Interest and other income/(expense), net on the Consolidated Statements of Operations. The allocation of other comprehensive income/(loss) to redeemable noncontrolling interests during the years ended December 31, 2014, 2013, and 2012 was $(133,000), $250,000, and $80,000, respectively.
Use of Estimates
The preparation of these financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates.
Market Concentration Risk
The Company is subject to increased exposure from economic and other competitive factors specific to markets where the Company holds a significant percentage of the carrying value of its real estate portfolio. At December 31, 2014, the Company held greater than 10% of the carrying value of its real estate portfolio in the Orange County, California; Metropolitan D.C.; and New York, New York markets.
United Dominion Reality L.P.
Entity Information [Line Items]
SIGNIFICANT ACCOUNTING POLICIES	SIGNIFICANT ACCOUNTING POLICIES
	Recent Accounting Pronouncements
	In April 2014, the FASB issued ASU No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, which incorporates a requirement that a disposition represent a strategic shift in an entity’s operations into the definition of a discontinued operation. In accordance with the ASU, a discontinued operation represents (1) a component of an entity or group of components that has been disposed of or is classified as held for sale in a single transaction and represents a strategic shift that has or will have a major effect on an entity’s financial results, or (2) an acquired business that is classified as held for sale on the date of acquisition. A strategic shift could include a disposal of (1) a separate major line of business, (2) a separate major geographic area of operations, (3) a major equity method investment, or (4) other major parts of an entity. The standard requires prospective application and will be effective for interim and annual periods beginning on or after December 15, 2014, with early adoption permitted. The early adoption provision excludes components of an entity that were sold or classified as held for sale prior to the adoption of the standard.
	The Operating Partnership elected to early adopt this standard effective January 1, 2014, which had a significant impact on the Operating Partnership’s consolidated financial statements as further discussed in Note 3, Discontinued Operations. Subsequent to the Operating Partnership’s adoption of ASU 2014-08, the sale of real estate that does not meet the definition of a discontinued operation under the standard is included in Gain/(loss) on sale of real estate owned, net of tax on the Consolidated Statements of Operations.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The updated standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The standard specifically excludes lease contracts. The ASU allows for the use of either the full or modified retrospective transition method, and the standard will be effective for the Operating Partnership on January 1, 2017; early adoption is not permitted. The Operating Partnership has not yet selected a transition method and we are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures.
	Real Estate
	Real estate assets held for investment are carried at historical cost and consist of land, buildings and improvements, furniture, fixtures and equipment and other costs incurred during their development, acquisition and redevelopment.
	Expenditures for ordinary repair and maintenance costs are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to the acquisition and/or improvement of real estate assets are capitalized and depreciated over their estimated useful lives if the expenditures qualify as a betterment or the life of the related asset will be substantially extended beyond the original life expectancy.
	The Operating Partnership purchases real estate investment properties and records the tangible and identifiable intangible assets and liabilities acquired based on their estimated fair value. The primary, although not only, identifiable intangible asset associated with our portfolio is the value of existing lease agreements. When recording the acquisition of a community, we first assign fair value to the estimated intangible value of the existing lease agreements and then to the estimated value of the land, building and fixtures assuming the community is vacant. The Operating Partnership estimates the intangible value of the lease agreements by determining the lost revenue associated with a hypothetical lease-up. Depreciation on the building is based on the expected useful life of the asset and the in-place leases are amortized over their remaining average contractual life. Property acquisition costs are expensed as incurred.
	Quarterly or when changes in circumstances warrant, the Operating Partnership will assess our real estate properties for indicators of impairment. In determining whether the Operating Partnership has indicators of impairment in our real estate assets, we assess whether the long-lived asset’s carrying value exceeds the community’s undiscounted future cash flows, which is representative of projected net operating income (“NOI”) plus the residual value of the community. Our future cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. If such indicators of impairment are present and the carrying value exceeds the undiscounted cash flows of the community, an impairment loss is recognized equal to the excess of the carrying amount of the asset over its estimated fair value. Our estimates of fair market value represent our best estimate based primarily upon unobservable inputs related to rental rates, operating costs, growth rates, discount rates and capitalization rates, industry trends and reference to market rates and transactions.
	For long-lived assets to be disposed of, impairment losses are recognized when the fair value of the asset less estimated cost to sell is less than the carrying value of the asset. Properties classified as real estate held for sale generally represent properties that are actively marketed or contracted for sale with the closing expected to occur within the next twelve months. Real estate held for sale is carried at the lower of cost, net of accumulated depreciation, or fair value, less the cost to sell, determined on an asset-by-asset basis. Expenditures for ordinary repair and maintenance costs on held for sale properties are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to held for sale properties are capitalized at cost. Depreciation is not recorded on real estate held for sale.
	Depreciation is computed on a straight-line basis over the estimated useful lives of the related assets which are 35 to 55 years for buildings, 10 to 35 years for major improvements, and 3 to 10 years for furniture, fixtures, equipment, and other assets.
	Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation. The Operating Partnership capitalizes costs directly related to the predevelopment, development, and redevelopment of a capital project, which include, but are not limited to, interest, real estate taxes, insurance, and allocated development and redevelopment overhead related to support costs for personnel working on the capital projects. We use our professional judgment in determining whether such costs meet the criteria for capitalization or must be expensed as incurred. These costs are capitalized only during the period in which activities necessary to ready an asset for its intended use are in progress and such costs are incremental and identifiable to a specific activity to get the asset ready for its intended use. These costs, excluding the direct costs of development and redevelopment and capitalized interest, for the years ended December 31, 2014, 2013, and 2012 were $2.0 million, $2.5 million, and $2.1 million, respectively. During the years ended December 31, 2014, 2013, and 2012, total interest capitalized was $2.9 million, $5.9 million, $3.7 million, respectively. As each home in a capital project is completed and becomes available for lease-up, the Operating Partnership ceases capitalization on the related portion and depreciation commences over the estimated useful life.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash on hand, demand deposits with financial institutions and short-term, highly liquid investments. We consider all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The majority of the Operating Partnership’s cash and cash equivalents are held at major commercial banks.
	Restricted Cash
	Restricted cash consists of escrow deposits held by lenders for real estate taxes, insurance and replacement reserves, and security deposits.
	Revenue and Real Estate Sales Gain Recognition
	Rental income related to leases is recognized on an accrual basis when due from residents and tenants in accordance with GAAP. Rental payments are generally due on a monthly basis and recognized when earned. The Operating Partnership recognizes interest income, management and other fees and incentives when earned, fixed and determinable.
	For sale transactions meeting the requirements for full accrual profit recognition, we remove the related assets and liabilities from our Consolidated Balance Sheets and record the gain or loss in the period the transaction closes. For sale transactions that do not meet the full accrual sale criteria due to our continuing involvement, we evaluate the nature of the continuing involvement and account for the transaction under an alternate method of accounting. Unless certain limited criteria are met, non-monetary transactions, including property exchanges, are accounted for at fair value.
	Sales to entities in which we or our General Partner retain or otherwise own an interest are accounted for as partial sales. If all other requirements for recognizing profit under the full accrual method have been satisfied and no other forms of continuing involvement are present, we recognize profit proportionate to the outside interest in the buyer and defer the gain on the interest we or our General Partner retain. The Operating Partnership recognizes any deferred gain when the property is sold to a third party. In transactions accounted by us as partial sales, we determine if the buyer of the majority equity interest in the venture was provided a preference as to cash flows in either an operating or a capital waterfall. If a cash flow preference has been provided, we recognize profit only to the extent that proceeds from the sale of the majority equity interest exceed costs related to the entire property.
	Derivative Financial Instruments
	The General Partner utilizes derivative financial instruments to manage interest rate risk and generally designates these financial instruments as cash flow hedges. Derivative financial instruments associated with the Operating Partnership’s allocation of the General Partner’s debt are recorded on our Consolidated Balance Sheets as either an asset or liability and measured quarterly at their fair value. The changes in fair value for the General Partner’s cash flow hedges allocated to the Operating Partnership that are deemed effective are reflected in other comprehensive income and for non-designated derivative financial instruments in earnings. The ineffective component of cash flow hedges, if any, is recorded in earnings.
	Noncontrolling Interests
	The noncontrolling interests represent the General Partner’s interests in certain consolidated subsidiaries and are presented in the capital section of the Consolidated Balance Sheets since these interests are not convertible or redeemable into any other ownership interests of the Operating Partnership.
	During the year ended December 31, 2013, the Operating Partnership corrected an error in the General Partner’s ownership interest in one of the consolidated subsidiaries. The correction increased the General Partner’s ownership interest resulting in a cumulative adjustment increasing Net (income)/loss attributable to noncontrolling interests by $3.3 million on the Consolidated Statements of Operations with a corresponding increase to Noncontrolling interests on the Consolidated Balance Sheets. Management believes the impact of the cumulative adjustment in 2013 is immaterial to the financial statements taken as a whole.
	Income Taxes
	The taxable income or loss of the Operating Partnership is reported on the tax returns of the partners. Accordingly, no provision has been made in the accompanying financial statements for federal or state income taxes on income that is passed through to the partners. However, any state or local revenue, excise or franchise taxes that result from the operating activities of the Operating Partnership are recorded at the entity level. The Operating Partnership’s tax returns are subject to examination by federal and state taxing authorities. Net income for financial reporting purposes differs from the net income for income tax reporting purposes primarily due to temporary differences, principally real estate depreciation and the tax deferral of certain gains on property sales. The differences in depreciation result from differences in the book and tax basis of certain real estate assets and the differences in the methods of depreciation and lives of the real estate assets.
	The Operating Partnership follows the accounting guidance within GAAP, with respect to how uncertain tax positions should be recognized, measured, presented, and disclosed in the financial statements. The guidance requires the accounting and disclosure of tax positions taken or expected to be taken in the course of preparing the Operating Partnership’s tax returns to determine whether the tax positions are “more-likely-than-not” of being sustained by the applicable tax authority. Tax positions not deemed to meet the more-likely-than-not threshold would be recorded as a tax benefit or expense in the current year. Management of the Operating Partnership is required to analyze all open tax years, as defined by the statute of limitations, for all major jurisdictions, which include federal and certain states. The Operating Partnership has no examinations in progress and none are expected at this time.
	Management of the Operating Partnership has reviewed all open tax years (2010 through 2013) and major jurisdictions, and concluded there is no tax liability resulting from unrecognized tax benefits relating to uncertain income tax positions taken or expected to be taken in future tax returns.
	Discontinued Operations
	Under GAAP, the results of operations for those properties sold during the year or classified as held for sale at the end of the current year are classified as discontinued operations in the current and prior periods. Further, to meet the discontinued operations criteria, the Operating Partnership or related parties will not have any significant continuing involvement in the ownership or operation of the property after the sale or disposition. Once a property is classified as held for sale, depreciation is no longer recorded. However, if the Operating Partnership determines that the property no longer meets the criteria for held for sale, the Operating Partnership will recapture any unrecorded depreciation on the property. The assets and liabilities, if any, of properties classified as held for sale are presented separately on the Consolidated Balance Sheets at lower of their carrying amount or their estimated fair value less the costs to sell the assets. (See Note 3, Discontinued Operations and Assets Held for Sale, for further discussion).
	Allocation of General and Administrative Expenses
	The Operating Partnership is charged directly for general and administrative expenses it incurs. The Operating Partnership is also charged with other general and administrative expenses that have been allocated by the General Partner to each of its subsidiaries, including the Operating Partnership, based on each subsidiary’s pro-rata portion of UDR’s total apartment homes. (See Note 6, Related Party Transactions.)
	Advertising Costs
	All advertising costs are expensed as incurred and reported on the Consolidated Statements of Operations within the line item General and administrative. During the years ended December 31, 2014, 2013, and 2012, total advertising expense from continuing and discontinued operations was $2.5 million, $2.5 million, and $2.4 million, respectively.
	Comprehensive Income/(Loss)
	Comprehensive income/(loss), which is defined as the change in capital during each period from transactions and other events and circumstances from nonowner sources, including all changes in capital during a period except for those resulting from investments by or distributions to partners, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the years ended December 31, 2014, 2013, and 2012, the Operating Partnership’s other comprehensive income/(loss) consisted of the gain/(loss) (effective portion) on derivative instruments that are designated as and qualify as cash flow hedges and (gain)/loss reclassified from other comprehensive income/(loss) into earnings. The (gain)/loss reclassified from other comprehensive income/(loss) is included in Interest expense on the Consolidated Statements of Operations. See Note 8, Derivatives and Hedging Activity, for further discussion.
	Use of Estimates
	The preparation of these financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates.
	Market Concentration Risk
	The Operating Partnership is subject to increased exposure from economic and other competitive factors specific to those markets where it holds a significant percentage of the carrying value of its real estate portfolio at December 31, 2014, the Operating Partnership held greater than 10% of the carrying value of its real estate portfolio in the Orange County, California; San Francisco, California; Metropolitan D.C.; and New York, New York markets.

Real_Estate_Owned_UNITED_DOMIN

Real Estate Owned (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
REAL ESTATE OWNED	REAL ESTATE OWNED
	Real estate assets owned by the Company consist of income producing operating properties, properties under development, land held for future development, and sold or held for sale properties. As of December 31, 2014, the Company owned and consolidated 139 communities in 10 states plus the District of Columbia totaling 39,851 apartment homes. The following table summarizes the carrying amounts for our real estate owned (at cost) as of December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Land and land improvements	$	1,980,221		$	1,847,127
	Depreciable property — held and used:
	Building, improvements, and furniture, fixtures and equipment	6,225,406			5,876,717
	Under development:
	Land	24,584			110,769
	Building, improvements, and furniture, fixtures and equipment	153,048			356,644
	Real estate held for disposition:
	Land	—			10,751
	Building, improvements, and furniture, fixtures and equipment	—			5,969
	Real estate owned	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Real estate owned, net	$	5,948,487		$	5,999,183
	During the year ended December 31, 2014, the Company sold nine communities consisting of a total of 2,500 apartment homes, an adjacent parcel of land, and one operating property for gross proceeds of $328.4 million, resulting in net proceeds of $324.4 million and a total gain, net of tax, of $138.6 million. A portion of the sale proceeds was designated for tax-deferred exchanges under Section 1031 of the Internal Revenue Code and was used to fund acquisitions of real estate as discussed below.
	In December 2014, the Company sold a 49% interest in 13th and Market and a 50% interest in 3033 Wilshire to MetLife for approximately $54.2 million and $8.3 million, respectively, and recognized, net of tax, a gain of $7.2 million and a loss of $2.2 million, respectively. Subsequent to the sale, the two communities are accounted for under the equity method of accounting and are included in Investment in and advances to unconsolidated joint ventures, net on the Consolidated Balance Sheets. See further discussion of this transaction in Note 5, Joint Ventures and Partnerships. The activity of the two communities prior to sale is classified as a component of continuing operations on the Consolidated Statements of Operations.
	In 2014, the Company acquired a fully-entitled land parcel for future development located in Huntington Beach, California for $77.8 million, two communities, located in Seattle, Washington and Kirkland, Washington, with a total of 358 apartment homes for $45.5 million and $75.2 million, respectively, a land parcel for future development located in Boston, Massachusetts for $32.2 million. The four acquisitions during the year ended December 31, 2014 were accomplished through tax-deferred exchanges under Section 1031 of the Internal Revenue Code.
	In June 2013, the Company sold a 50% interest in five partnerships (the “UDR/MetLife Vitruvian Park® Partnerships”) to MetLife for approximately $141.3 million, before transaction costs of $936,000. The properties held by the UDR/MetLife Vitruvian Park® Partnerships are located in Addison, Texas and consist of two operating communities with 739 apartment homes, one recently completed development community in lease-up with 391 apartment homes, and 28.4 acres of developable land parcels. The transaction resulted in a gain of approximately $436,000 which the Company has deferred until the terms of the construction completion guarantee have been met. The UDR/MetLife Vitruvian Park® Partnerships are accounted for under the equity method of accounting and are included in Investment In and Advances To Unconsolidated Joint Ventures, Net on the Consolidated Balance Sheets. See further discussion of this transaction in Note 5, Joint Ventures and Partnerships.
	The operations of the UDR/MetLife Vitruvian Park® Partnerships' assets, prior to the sale of a 50% interest, have been classified as a component of continuing operations on the Consolidated Statements of Operations, as UDR has continuing involvement over the duration of the partnership.
	In December 2013, the Company sold a 49% interest to MetLife in the Company’s fully-entitled 399 Fremont land parcel located in San Francisco, California for approximately $29.9 million. In conjunction with the sale, the Company formed a new unconsolidated joint venture, UDR/MetLife 399 Fremont, to develop a $318 million, 447-home, luxury high-rise tower on the site. As the Company recently acquired the 399 Fremont land parcel, the sale price was equivalent to the cost basis resulting in no gain or loss on the transaction. For more information on this transaction see Note 5, Joint Ventures and Partnerships.
	In December 2013, the Company became the managing partner of two joint ventures resulting in consolidation of both and increasing the real estate owned by $129.4 million. See Note 5, Joint Ventures and Partnerships, for further details.
	The Company incurred $373,000, $59,000 and $2.3 million of acquisition-related costs during the years ended December 31, 2014, 2013, and 2012, respectively. These expenses are reported within the line item General and Administrative on the Consolidated Statements of Operations.
	In February 2015, the Company acquired an office building in Highlands Ranch, Colorado, for total consideration of approximately $24.0 million, which was comprised of assumed debt. The Company’s corporate offices, as well as other leased office space, are located in the acquired building. The building consists of approximately 120,000 square feet, of which UDR occupies approximately 44,000 square feet. All existing leases were assumed by the Company at the time of the acquisition.
United Dominion Reality L.P.
Entity Information [Line Items]
REAL ESTATE OWNED	REAL ESTATE OWNED
	Real estate assets owned by the Operating Partnership consists of income producing operating properties, properties under development, land held for future development, and sold or held for sale properties. At December 31, 2014, the Operating Partnership owned and consolidated 68 communities in nine states plus the District of Columbia totaling 20,814 apartment homes. The following table summarizes the carrying amounts for our real estate owned (at cost) as of December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Land	$	1,008,014		$	1,004,447
	Depreciable property — held and used:
	Buildings, improvements, and furniture, fixtures and equipment	3,230,756			3,103,970
	Under development:
	Land	—			9,447
	Construction in progress	—			70,616
	Real estate owned	4,238,770			4,188,480
	Accumulated depreciation	(1,403,303		)	(1,241,574		)
	Real estate owned, net	$	2,835,467		$	2,946,906
	The Operating Partnership had no acquisitions during the years ended December 31, 2014, 2013 and 2012.
	During the year ended December 31, 2014, the Operating Partnership sold one community and an adjacent parcel of land in San Diego, California for gross proceeds of $48.7 million, resulting in a $24.4 million gain and net proceeds of $47.9 million. The Operating Partnership also recorded a gain of $39.2 million in connection with the sale of two communities, one in Tampa, Florida and one in Los Angeles, California, which was previously deferred. The total gains of $63.6 million were included in Gain/(loss) on sale of real estate owned on the Consolidated Statements of Operations.
	In November 2013, the Operating Partnership distributed the development property Los Alisos to the General Partner. See Note 6, Related Party Transactions, for more details.

Discontinued_Operations_UNITED

Discontinued Operations (UNITED DOMINION REALTY, L.P.) (United Dominion Reality L.P.)	12 Months Ended
	Dec. 31, 2014
United Dominion Reality L.P.
Entity Information [Line Items]
DISCONTINUED OPERATIONS	DISCONTINUED OPERATIONS AND ASSETS HELD FOR SALE
	Effective January 1, 2014, UDR, L.P. prospectively adopted ASU No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, for all communities not previously sold or classified as held for sale. The standard had a material impact on the Operating Partnership’s consolidated financial statements. As a result of adopting the ASU, during the year ended December 31, 2014, gains, net of tax, of $62.5 million from disposition of real estate, excluding a $1.1 million gain related to the sale of land, are included in Gain/(loss) on sale of real estate owned, net of tax on the Consolidated Statements of Operations rather than in Income/(loss) from discontinued operations, net of tax on the Consolidated Statements of Operations.
	Prior to the prospective adoption of ASU 2014-08, FASB Accounting Standards Codification ("ASC") Subtopic 205-20 required, among other things, that the primary assets and liabilities and the results of operations of the Operating Partnership’s real properties that have been sold or are held for disposition, be classified as discontinued operations and segregated in UDR, L.P.’s Consolidated Statements of Operations and Consolidated Balance Sheets. Consequently, the primary assets and liabilities and the net operating results of those properties sold or classified as held for disposition prior to January 1, 2014 are accounted for as discontinued operations for all periods presented. This presentation does not have an impact on net income available to common stockholders; it only results in the reclassification of the operating results within the Consolidated Statements of Operations for the periods ended December 31, 2014, 2013, and 2012.
	During the year ended December 31, 2013, the Operating Partnership sold two communities in the Sacramento market with 914 apartment homes for gross proceeds of $81.1 million. During the year ended December 31, 2012, the Operating Partnership sold four communities with 1,314 apartment homes. At December 31, 2014 and 2013, the Operating Partnership had no communities that met the criteria to be classified as held for sale and included in Income/(loss) from discontinued operations on the Consolidated Statements of Operations.
	During the years ended December 31, 2014, 2013, and 2012, the Operating Partnership recognized net gain/(loss) on the sale of depreciable properties of $0, $41.5 million, and $51.1 million, respectively, in Income/(loss) from discontinued operations on the Consolidated Statements of Operations.
	The following is a summary of income from discontinued operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014		2013		2012
	Rental income	$	—	$	8,989	$	15,745
	Rental expenses	—		3,149		5,444
	Property management	—		247		432
	Real estate depreciation	—		1,935		3,320
	Income/(loss) attributable to disposed properties	—		3,658		6,549
	Net gain/(loss) on the sale of depreciable properties	—		41,518		51,094
	Income/(loss) from discontinued operations	$	—	$	45,176	$	57,643

Debt_UNITED_DOMINION_REALTY_LP

Debt (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
DEBT	SECURED AND UNSECURED DEBT
	The following is a summary of our secured and unsecured debt at December 31, 2014 and 2013 (dollars in thousands):
		Principal Outstanding						For the Year Ended December 31, 2014
								Weighted Average			Weighted Average			Number of Communities
		December 31,						Interest Rate			Years to Maturity			Encumbered
		2014			2013
	Secured Debt:
	Fixed Rate Debt
	Mortgage notes payable (a)	$	401,210		$	445,706		5.46	%		1.6			6
	Fannie Mae credit facilities (b)	568,086			626,667			5.12	%		4			22
	Total fixed rate secured debt	969,296			1,072,373			5.26	%		3			28
	Variable Rate Debt
	Mortgage notes payable	31,337			63,595			1.94	%		2.1			1
	Tax-exempt secured notes payable (c)	94,700			94,700			0.83	%		8.2			2
	Fannie Mae credit facilities (b)	266,196			211,409			1.6	%		5.2			7
	Total variable rate secured debt	392,233			369,704			1.44	%		5.7			10
	Total Secured Debt	1,361,529			1,442,077			4.16	%		3.8			38
	Unsecured Debt:
	Commercial Banks
	Borrowings outstanding under an unsecured credit facility due December 2017 (d) (h)	152,500			—			1.09	%		2.9
	Senior Unsecured Notes
	5.13% Medium-Term Notes due January 2014 (e)	—			184,000			—	%		—
	5.50% Medium-Term Notes due April 2014 (net of discount of $20) (e)	—			128,480			—	%		—
	5.25% Medium-Term Notes due January 2015 (net of discounts of $6 and $134, respectively) (f)	325,169			325,041			5.25	%		—
	5.25% Medium-Term Notes due January 2016	83,260			83,260			5.25	%		1
	4.25% Medium-Term Notes due June 2018 (net of discounts of $1,465 and $1,893, respectively) (h)	298,535			298,107			4.25	%		3.4
	2.17% Term Notes due June 2018 (h)	215,000			250,000			2.17	%		3.4
	1.53% Term Notes due June 2018 (h)	100,000			65,000			1.53	%		3.4
	1.31% Term Notes due June 2018 (h)	35,000			35,000			1.31	%		3.4
	3.70% Medium-Term Notes due October 2020 (net of discounts of $46 and $54, respectively) (h)	299,954			299,946			3.7	%		5.8
	4.63% Medium-Term Notes due January 2022 (net of discounts of $2,523 and $2,882, respectively) (h)	397,477			397,118			4.63	%		7
	3.75% Medium-Term Notes due July 2024 (net of discount of $990) (g) (h)	299,010			—			3.75	%		9.5
	8.50% Debentures due September 2024	15,644			15,644			8.5	%		9.7
	Other	27			30			N/A			N/A
	Total Unsecured Debt	2,221,576			2,081,626			3.81	%		4.6
	Total Debt	$	3,583,105		$	3,523,703		3.94	%		4.3
	Our secured debt instruments generally feature either monthly interest and principal or monthly interest-only payments with balloon payments due at maturity. For purposes of classification of the above table, variable rate debt with a derivative financial instrument designated as a cash flow hedge is deemed as fixed rate debt due to the Company having effectively established a fixed interest rate for the underlying debt instrument. As of December 31, 2014, secured debt encumbered $2.2 billion or 26.6% of UDR’s total real estate owned based upon gross book value ($6.2 billion or 73.4% of UDR’s real estate owned based on gross book value is unencumbered).
	(a) At December 31, 2014, fixed rate mortgage notes payable are generally due in monthly installments of principal and interest and mature at various dates from December 2015 through May 2019 and carry interest rates ranging from 3.43% to 5.94%.
	The Company will from time to time acquire properties subject to fixed rate debt instruments. In those situations, management will record the secured debt at its estimated fair value and amortize any difference between the fair value and par to interest expense over the life of the underlying debt instrument. During the years ended December 31, 2014, 2013, and 2012, the Company had $5.1 million, $5.1 million, and $4.9 million, respectively, of amortization expense on the fair market adjustment of debt assumed in acquisition of properties, which was included in Interest expense on the Consolidated Statements of Operations. The unamortized fair market adjustment was a net premium of $6.7 million and $11.8 million at December 31, 2014 and 2013, respectively.
	(b) UDR has three secured credit facilities with Fannie Mae with an aggregate commitment of $834.3 million at December 31, 2014. The Fannie Mae credit facilities are for terms of seven to ten years (maturing at various dates from May 2017 through July 2023) and bear interest at floating and fixed rates. At December 31, 2014, we have $568.1 million of the outstanding balance is fixed at a weighted average interest rate of 5.12% and the remaining balance of $266.2 million on these facilities is currently at a weighted average variable interest rate of 1.60%.
	Further information related to these credit facilities is as follows (dollars in thousands):
		December 31, 2014			31-Dec-13
	Borrowings outstanding	$	834,282		$	838,076
	Weighted average borrowings during the period ended	835,873			839,597
	Maximum daily borrowings during the period ended	837,564			841,494
	Weighted average interest rate during the period ended	4.1		%	4.2		%
	Weighted average interest rate at the end of the period	4		%	4.1		%
	(c) The variable rate mortgage notes payable that secure tax-exempt housing bond issues mature on August 2019 and March 2032. Interest on these notes is payable in monthly installments. The variable mortgage notes have interest rates of 0.78% and 0.93%, respectively, as of December 31, 2014.
	(d) The Company has a $900 million unsecured revolving credit facility with a maturity date to December 2017, a six month extension option, and an accordion feature that allows the Company to increase the facility to $1.45 billion. Based on the Company's current credit rating, the credit facility carries an interest rate equal to LIBOR plus a spread of 100 basis points and a facility fee of 15 basis points. As of December 31, 2014, the Company had a balance of $152.5 million outstanding under the revolving credit facility.
	The following is a summary of short-term bank borrowings under UDR’s bank credit facility at December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Total revolving credit facility	$	900,000		$	900,000
	Borrowings outstanding at end of period (1)	152,500			—
	Weighted average daily borrowings during the period ended	291,761			169,844
	Maximum daily borrowings during the period ended	625,000			372,000
	Weighted average interest rate during the period ended	1.2		%	1.2		%
	Interest rate at end of the period	1.1		%	1.3		%
	(1) Excludes $1.9 million and $2.2 million of letters of credit at December 31, 2014 and 2013, respectively.
	(e) Paid off at maturity with borrowings under the Company’s $900 million unsecured revolving credit facility.
	(f)	In January 2015, we paid off $325.2 million of 5.25% medium-term notes due January 2015 with borrowings under the Company’s $900 million unsecured revolving credit facility.
	(g) In June 2014, the Company issued $300 million of 3.750% senior unsecured medium-term notes due July 1, 2024. Interest is payable semi-annually beginning on January 1, 2015. These notes were issued at 99.652% of the principal amount and had a discount of $1.0 million at December 31, 2014. The Company used the net proceeds to pay down borrowings outstanding on our $900 million unsecured credit facility and for general corporate purposes.
	(h) The Operating Partnership is a guarantor at December 31, 2014 and 2013.
	The aggregate maturities, including amortizing principal payments of secured debt, of total debt for the next five years subsequent to December 31, 2014 are as follows (dollars in thousands):
	Year		Secured Fixed Rate Debt			Secured Variable Rate Debt			Total Secured Debt				Total Unsecured Debt (a)			Total Debt
2015		$	196,648		$	—		$	196,648			$	324,286		$	520,934
2016		135,167			31,337			166,504				82,377			248,881
2017		177,774			65,000			242,774				152,500			395,274
2018		120,969			104,787			225,756				648,443			874,199
2019		248,738			67,700			316,438				—			316,438
Thereafter		90,000			123,409			213,409				1,013,970			1,227,379
Total		$	969,296		$	392,233		$	1,361,529			$	2,221,576		$	3,583,105
(a) With the exception of the 1.31% Term Notes due June 2018 and revolving credit facility which carry a variable interest rate, all unsecured debt carries fixed interest rates.
We were in compliance with the covenants of our debt instruments at December 31, 2014.
United Dominion Reality L.P.
Entity Information [Line Items]
DEBT	DEBT
	Our secured debt instruments generally feature either monthly interest and principal or monthly interest-only payments with balloon payments due at maturity. For purposes of classification in the following table, variable rate debt with a derivative financial instrument designated as a cash flow hedge is deemed as fixed rate debt due to the Operating Partnership having effectively established the fixed interest rate for the underlying debt instrument. Secured debt consists of the following as of December 31, 2014 and 2013 (dollars in thousands):
		Principal Outstanding						For the Year Ended December 31, 2014
		December 31,						Weighted Average			Weighted Average			Number of Communities
		2014			2013			Interest Rate			Years to Maturity			Encumbered
	Fixed Rate Debt
	Mortgage notes payable	$	378,371		$	386,803		5.47	%		1.6			5
	Fannie Mae credit facilities	333,828			379,003			4.9	%		4.6			10
	Total fixed rate secured debt	712,199			765,806			5.2	%		3			15
	Variable Rate Debt
	Tax-exempt secured note payable	27,000			27,000			0.93	%		17.2			1
	Fannie Mae credit facilities	192,760			142,059			1.83	%		6			5
	Total variable rate secured debt	219,760			169,059			1.72	%		7.4			6
	Total secured debt	$	931,959		$	934,865		4.38	%		4			21
	As of December 31, 2014, an aggregate commitment of $526.6 million of the General Partner's secured credit facilities with Fannie Mae was allocated to the Operating Partnership based on the ownership of the assets securing the debt. The entire commitment was outstanding at December 31, 2014. The Fannie Mae credit facilities mature at various dates from May 2017 through July 2023 and bear interest at floating and fixed rates. At December 31, 2014, $333.8 million of the outstanding balance was fixed at a weighted average interest rate of 4.90% and the remaining balance of $192.8 million on these facilities had a weighted average variable interest rate of 1.83%. During 2013, the General Partner reallocated an additional $13.7 million of the Fannie Mae credit facilities to the Operating Partnership. The following is information related to the credit facilities allocated to the Operating Partnership (dollars in thousands):
		December 31, 2014			December 31, 2013
	Borrowings outstanding	$	526,588		$	521,062
	Weighted average borrowings during the period ended	527,592			522,007
	Maximum daily borrowings during the period ended	528,659			523,187
	Weighted average interest rate during the period ended	4.1		%	4.2		%
	Interest rate at the end of the period	4		%	4.1		%
	The Operating Partnership may from time to time acquire properties subject to fixed rate debt instruments. In those situations, management will record the secured debt at its estimated fair value and amortize any difference between the fair value and par to interest expense over the life of the underlying debt instrument. The unamortized fair value adjustment of the fixed rate debt instruments on the Operating Partnership’s properties was a net premium of $6.2 million and $10.0 million at December 31, 2014 and 2013, respectively.
	Fixed Rate Debt
	Mortgage notes payable. Fixed rate mortgage notes payable are generally due in monthly installments of principal and interest and mature at various dates from December 2015 through May 2019 and carry interest rates ranging from 3.43% to 5.94%.
	Secured credit facilities. At December 31, 2014, the General Partner had borrowings against its fixed rate facilities of $568.1 million, of which $333.8 million was allocated to the Operating Partnership based on the ownership of the assets securing the debt. As of December 31, 2014, the fixed rate Fannie Mae credit facilities allocated to the Operating Partnership had a weighted average fixed interest rate of 4.90%.
	Variable Rate Debt
	Tax-exempt secured note payable. The variable rate mortgage note payable that secures tax-exempt housing bond issues matures in March 2032. Interest on this note is payable in monthly installments. The mortgage note payable has an interest rate of 0.93% as of December 31, 2014.
	Secured credit facilities. At December 31, 2014, the General Partner had borrowings against its variable rate facilities of $266.2 million, of which $192.8 million was allocated to the Operating Partnership based on the ownership of the assets securing the debt. As of December 31, 2014, the variable rate borrowings under the Fannie Mae credit facilities allocated to the Operating Partnership had a weighted average floating interest rate of 1.83%.
	The aggregate maturities of the Operating Partnership’s secured debt due during each of the next five calendar years subsequent to December 31, 2014 are as follows (dollars in thousands):
		Fixed						Variable
		Mortgage			Secured Credit			Tax-Exempt				Secured Credit			Total
		Notes Payable			Facilities			Secured Notes Payable				Facilities
	2015	$	192,637		$	366		$	—			$	—		$	193,003
	2016	130,951			385			—				—			131,336
	2017	913			15,640			—				6,566			23,119
	2018	968			111,052			—				96,974			208,994
	2019	52,902			123,096			—				—			175,998
	Thereafter	—			83,289			27,000				89,220			199,509
	Total	$	378,371		$	333,828		$	27,000			$	192,760		$	931,959
	Guarantor on Unsecured Debt
	The Operating Partnership is a guarantor on the General Partner’s unsecured revolving credit facility, with an aggregate borrowing capacity of $900 million, $250 million of term notes due June 2018, $100 million of term notes due June 2018, $300 million of medium-term notes due June 2018, $300 million of medium-term notes due October 2020, $400 million of medium-term notes due January 2022, and $300 million of medium-term notes due July 2024. As of December 31, 2014, there were $152.5 million outstanding borrowings under the unsecured credit facility. As of December 31, 2013, there was no outstanding balance under the unsecured credit facility.

Related_Party_Transactions_UNI

Related Party Transactions (UNITED DOMINION REALTY, L.P.) (United Dominion Reality L.P.)	12 Months Ended
	Dec. 31, 2014
United Dominion Reality L.P.
Entity Information [Line Items]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS
	Advances (To)/From the General Partner
	The Operating Partnership participates in the General Partner’s central cash management program, wherein all the Operating Partnership’s cash receipts are remitted to the General Partner and all cash disbursements are funded by the General Partner. In addition, other miscellaneous costs such as administrative expenses are incurred by the General Partner on behalf of the Operating Partnership. As a result of these various transactions between the Operating Partnership and the General Partner, the Operating Partnership had net advances (to)/from the General Partner of $13.6 million and $(9.9) million at December 31, 2014 and 2013, respectively, which is reflected as an increase/(reduction) of capital on the Consolidated Balance Sheets.
	Allocation of General and Administrative Expenses
	The General Partner provides various general and administrative and other overhead services for the Operating Partnership including legal assistance, acquisitions analysis, marketing and advertising, and allocates these expenses to the Operating Partnership first on the basis of direct usage when identifiable, with the remainder allocated based on its pro-rata portion of UDR’s total apartment homes. During the years ended December 31, 2014, 2013, and 2012, the general and administrative expenses allocated to the Operating Partnership by UDR were $27.4 million, $23.5 million, and $25.2 million, respectively, and are included in General and administrative on the Consolidated Statements of Operations. In the opinion of management, this method of allocation reflects the level of services received by the Operating Partnership from the General Partner.
	During the years ended December 31, 2014, 2013, and 2012, the Operating Partnership incurred $12.7 million, $12.3 million, and $11.9 million, respectively, of related party management fees related to a management agreement entered into in 2011 with wholly-owned subsidiaries of our TRS. (See further discussion in paragraph below.) These related party management fees are initially recorded within the line item General and administrative on the Consolidated Statements of Operations, and a portion related to management fees charged by the TRS of the General Partner is reclassified to Property management on the Consolidated Statements of Operations. (See further discussion below.)
	Management Fee
	In 2011, the Operating Partnership entered into a management agreement with wholly-owned subsidiaries of our TRS. Under the management agreement, the Operating Partnership is charged a management fee equal to 2.75% of gross rental revenues, which is reported in Property management on the Consolidated Statements of Operations.
	Guaranties by the General Partner
	The Operating Partnership provided a “bottom dollar” guaranty to certain limited partners as part of their original contribution to the Operating Partnership. The guaranty protects the tax basis of the underlying contribution and is reflected on the OP unitholder’s Schedule K-1 tax form. The guaranty was made in the form of a note payable issued by the Operating Partnership to the General Partner at an annual interest rate of 5.18% for the years ended December 31, 2014 and 2013, respectively. On December 31, 2013, the note was renewed at an annual interest rate of 5.18%. Interest payments are made monthly and the renewed note is due December 31, 2023. At December 31, 2014 and 2013, the note payable due to the General Partner was $83.2 million, respectively.
	In 2011, the Operating Partnership also provided a “bottom dollar” guaranty in conjunction with 1,802,239 OP Units issued in partial consideration to the seller for the acquisition of an operating community. The guaranty was made in the form of a note payable issued by the Operating Partnership to the General Partner at an annual interest rate of 5.34%. Interest payments are due monthly and the note matures on August 31, 2021. At December 31, 2014 and 2013, the note payable due to the General Partner was $5.5 million.
	In November 2013, the Operating Partnership distributed the development property Los Alisos to the General Partner as a capital distribution. Upon the distribution of the property, the Operating Partnership redeemed 1,002,556 limited partnership units owned by UDR and affiliated entities and reduced its receivable from the General Partner by $53.7 million, resulting in a net capital reduction of $77.0 million.

Fair_Value_of_Derivatives_and_1

Fair Value of Derivatives and Financial Instruments (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS	FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS
	Fair value is based on the price that would be received to sell an asset or the exit price that would be paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three-level valuation hierarchy prioritizes observable and unobservable inputs used to measure fair value. The fair value hierarchy consists of three broad levels, which are described below:
	•	Level 1 — Quoted prices in active markets for identical assets or liabilities that the entity has the ability to access.
	•	Level 2 — Observable inputs other than prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated with observable market data.
	•	Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.
	The estimated fair values of the Company’s financial instruments either recorded or disclosed on a recurring basis as of December 31, 2014 and 2013 are summarized as follows (dollars in thousands):
						Fair Value at December 31, 2014, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2014		Fair Value Estimate at December 31, 2014		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs
						Assets or		Inputs		(Level 3)
						Liabilities		(Level 2)
						(Level 1)
	Description:
	Notes receivable (a)	$	14,369	$	14,808	$	—	$	—	$	14,808
	Derivatives - Interest rate contracts (b)	88		88		—		88		—
	Total assets	$	14,457	$	14,896	$	—	$	88	$	14,808
	Derivatives - Interest rate contracts (b)	$	10,368	$	10,368	$	—	$	10,368	$	—
	Secured debt instruments - fixed rate: (c)
	Mortgage notes payable	401,210		415,663		—		—		415,663
	Fannie Mae credit facilities	568,086		606,623		—		—		606,623
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	31,337		31,337		—		—		31,337
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	266,196		266,196		—		—		266,196
	Unsecured debt instruments (c):
	Commercial banks	152,500		152,500		—		—		152,500
	Senior unsecured notes	2,069,076		2,144,125		—		—		2,144,125
	Total liabilities	$	3,593,473	$	3,721,512	$	—	$	10,368	$	3,711,144
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	282,480	$	282,480	$	—	$	282,480	$	—
						Fair Value at December 31, 2013, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2013		Fair Value Estimate at December 31, 2013		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs (Level 3)
						Assets or		Inputs (Level 2)
						Liabilities (Level 1)
	Description:
	Notes receivable (a)	$	83,033	$	83,833	$	—	$	—	83,833
	Total assets	$	83,033	$	83,833	$	—	$	—	$	83,833
	Derivatives- Interest rate contracts (b)	$	4,965	$	4,965	$	—	$	4,965	$	—
	Secured debt instruments- fixed rate: (c)
	Mortgage notes payable	445,706		466,375		—		—		466,375
	Fannie Mae credit facilities	626,667		661,094		—		—		661,094
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	63,595		63,595		—		—		63,595
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	211,409		211,409		—		—		211,409
	Unsecured debt instruments: (c)
	Senior unsecured notes	2,081,626		2,149,003		—		—		2,149,003
	Total liabilities	$	3,528,668	$	3,651,141	$	—	$	4,965	$	3,646,176
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	217,597	$	217,597	$	—	$	217,597	$	—
	(a)	See Note 2, Significant Accounting Policies.
	(b)	See Note 13, Derivatives and Hedging Activity.
	(c)	See Note 6, Secured Debt and Unsecured Debt.
	(d)	See Note 11, Noncontrolling Interests.
	There were no transfers into or out of each of the levels of the fair value hierarchy.
	Financial Instruments Carried at Fair Value
	The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The fair values of interest rate options are determined using the market standard methodology of discounting the future expected cash receipts that would occur if variable interest rates rise above the strike rate of the caps. The variable interest rates used in the calculation of projected receipts on the cap are based on an expectation of future interest rates derived from observable market interest rate curves and volatilities.
	The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees.
	Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. However, as of December 31, 2014 and 2013, the Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. In conjunction with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio.
	Redeemable noncontrolling interests in the Operating Partnership have a redemption feature and are marked to their redemption value. The redemption value is based on the fair value of the Company’s common stock at the redemption date, and therefore, is calculated based on the fair value of the Company’s common stock at the balance sheet date. Since the valuation is based on observable inputs such as quoted prices for similar instruments in active markets, redeemable noncontrolling interests in the Operating Partnership are classified as Level 2.
	Financial Instruments Not Carried at Fair Value
	At December 31, 2014, the fair values of cash and cash equivalents, restricted cash, accounts receivable, prepaids, real estate taxes payable, accrued interest payable, security deposits and prepaid rent, distributions payable and accounts payable approximated their carrying values because of the short term nature of these instruments. The estimated fair values of other financial instruments were determined by the Company using available market information and appropriate valuation methodologies. Considerable judgment is necessary to interpret market data and develop estimated fair values. Accordingly, the estimates presented herein are not necessarily indicative of the amounts the Company would realize on the disposition of the financial instruments. The use of different market assumptions or estimation methodologies may have a material effect on the estimated fair value amounts.
	We estimate the fair value of our notes receivable and debt instruments by discounting the remaining cash flows of the debt instrument at a discount rate equal to the replacement market credit spread plus the corresponding treasury yields. Factors considered in determining a replacement market credit spread include general market conditions, borrower specific credit spreads, time remaining to maturity, loan-to-value ratios and collateral quality, where applicable (Level 3).
We record impairment losses on long-lived assets used in operations when events and circumstances indicate that the assets might be impaired and the undiscounted cash flows estimated to be generated by the future operation and disposition of those assets are less than the net book value of those assets. Our cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. The net book value of impaired assets is reduced to fair value. Our estimates of fair value represent our best estimate based upon Level 3 inputs such as industry trends and reference to market rates and transactions.
We consider various factors to determine if a decrease in the value of our investment in and advances to unconsolidated joint ventures, net is other-than-temporary. These factors include, but are not limited to, age of the venture, our intent and ability to retain our investment in the entity, the financial condition and long-term prospects of the entity, and the relationships with the other joint venture partners and its lenders. Based on the significance of the unobservable inputs, we classify these fair value measurements within Level 3 of the valuation hierarchy. The Company did not incur any other-than-temporary decrease in the value of its investments in unconsolidated joint ventures during the years ended December 31, 2014, 2013, and 2012.
After determining an other-than-temporary decrease in the value of an equity method investment has occurred, we estimate the fair value of our investment by estimating the proceeds we would receive upon a hypothetical liquidation of the investment at the date of measurement. Inputs reflect management’s best estimate of what market participants would use in pricing the investment giving consideration to the terms of the joint venture agreement and the estimated discounted future cash flows to be generated from the underlying joint venture assets. The inputs and assumptions utilized to estimate the future cash flows of the underlying assets are based upon the Company’s evaluation of the economy, market trends, operating results, and other factors, including judgments regarding costs to complete any construction activities, lease up and occupancy rates, rental rates, inflation rates, capitalization rates utilized to estimate the projected cash flows at the disposition, and discount rates.
United Dominion Reality L.P.
Entity Information [Line Items]
FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS	FAIR VALUE OF DERIVATIVES AND FINANCIAL INSTRUMENTS
	Fair value is based on the price that would be received to sell an asset or the exit price that would be paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three-level valuation hierarchy prioritizes observable and unobservable inputs used to measure fair value. The fair value hierarchy consists of three broad levels, which are described below:
	•	Level 1 — Quoted prices in active markets for identical assets or liabilities that the entity has the ability to access.
	•	Level 2 — Observable inputs other than prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated with observable market data.
	•	Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.
	The estimated fair values of the Operating Partnership’s financial instruments either recorded or disclosed on a recurring basis as of December 31, 2014 and 2013 are summarized as follows (dollars in thousands):
						Fair Value at December 31, 2014, Using
		Total Carrying Amount in Statement of Financial Position at		Fair Value Estimate at		Quoted Prices in		Significant Other		Significant
						Active Markets		Observable		Unobservable
						for Identical		Inputs		Inputs
						Assets or		(Level 2)		(Level 3)
						Liabilities
		December 31, 2014		December 31, 2014		(Level 1)
	Description:
	Derivatives- Interest rate contracts (a)	$	39	$	39	$	—	$	39	$	—
	Total assets	$	39	$	39	$	—	$	39	$	—
	Derivatives - Interest rate contracts (a)	$	918	$	918	$	—	$	918	$	—
	Secured debt instruments - fixed rate: (b)
	Mortgage notes payable	378,371		391,835		—		—		391,835
	Fannie Mae credit facilities	333,828		355,470		—		—		355,470
	Secured debt instruments - variable rate: (b)
	Tax-exempt secured notes payable	27,000		27,000		—		—		27,000
	Fannie Mae credit facilities	192,760		192,760		—		—		192,760
	Total liabilities	$	932,877	$	967,983	$	—	$	918	$	967,065
						Fair Value at December 31, 2013, Using
		Total Carrying Amount in Statement of Financial Position at		Fair Value Estimate at		Quoted Prices in		Significant Other		Significant
						Active Markets		Observable		Unobservable
						for Identical		Inputs		Inputs
						Assets or		(Level 2)		(Level 3)
						Liabilities
		December 31, 2013		December 31, 2013		(Level 1)
	Description:
	Derivatives- Interest rate contracts (a)	$	2,731	$	2,731	$	—	$	2,731	$	—
	Secured debt instruments - fixed rate: (b)
	Mortgage notes payable	386,803		403,695		—		—		403,695
	Fannie Mae credit facilities	379,003		394,239		—		—		394,239
	Secured debt instruments - variable rate: (b)
	Tax-exempt secured notes payable	27,000		27,000		—		—		27,000
	Fannie Mae credit facilities	142,059		142,059		—		—		142,059
	Total liabilities	$	937,596	$	969,724	$	—	$	2,731	$	966,993
	(a)	See Note 8, Derivatives and Hedging Activity.
	(b)	See Note 5, Debt.
	There were no transfers into or out of each of the levels of the fair value hierarchy.
	Financial Instruments Carried at Fair Value
	The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The fair values of interest rate options are determined using the market standard methodology of discounting the future expected cash receipts that would occur if variable interest rates rise above the strike rate of the caps. The variable interest rates used in the calculation of projected receipts on the cap are based on an expectation of future interest rates derived from observable market interest rate curves and volatilities.
	The Operating Partnership incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Operating Partnership has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees.
	Although the Operating Partnership has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. However, as of December 31, 2014 and December 31, 2013, the Operating Partnership has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Operating Partnership has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. In conjunction with the FASB’s fair value measurement guidance, the Operating Partnership made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio.
	Financial Instruments Not Carried at Fair Value
	At December 31, 2014, the fair values of cash and cash equivalents, restricted cash, accounts receivable, prepaids, real estate taxes payable, accrued interest payable, security deposits and prepaid rent, distributions payable and accounts payable approximated their carrying values because of the short term nature of these instruments. The estimated fair values of other financial instruments were determined by the Operating Partnership using available market information and appropriate valuation methodologies. Considerable judgment is necessary to interpret market data and develop estimated fair values. Accordingly, the estimates presented herein are not necessarily indicative of the amounts the Operating Partnership would realize on the disposition of the financial instruments. The use of different market assumptions or estimation methodologies may have a material effect on the estimated fair value amounts.
	The General Partner estimates the fair value of our debt instruments by discounting the remaining cash flows of the debt instrument at a discount rate equal to the replacement market credit spread plus the corresponding treasury yields. Factors considered in determining a replacement market credit spread include general market conditions, borrower specific credit spreads, time remaining to maturity, loan-to-value ratios and collateral quality (Level 3).
	The Operating Partnership records impairment losses on long-lived assets used in operations when events and circumstances indicate that the assets might be impaired and the undiscounted cash flows estimated to be generated by the future operation and disposition of those assets are less than the net book value of those assets. Cash flow estimates are based upon historical results adjusted to reflect management’s best estimate of future market and operating conditions and our estimated holding periods. The net book value of impaired assets is reduced to fair value. The General Partner’s estimates of fair value represent management’s estimates based upon Level 3 inputs such as industry trends and reference to market rates and transactions.

Derivatives_and_Hedging_Activi1

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
DERIVATIVES AND HEDGING ACTIVITY	DERIVATIVES AND HEDGING ACTIVITY
	Risk Management Objective of Using Derivatives
	The Company is exposed to certain risks arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk primarily by managing the amount, sources, and duration of its debt funding and through the use of derivative financial instruments. Specifically, the Company may enter into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s investments and borrowings.
	Cash Flow Hedges of Interest Rate Risk
	The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company primarily uses interest rate swaps and caps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Interest rate caps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty if interest rates rise above the strike rate on the contract in exchange for an up front premium.
	The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in Accumulated other comprehensive income/(loss), net in the Consolidated Balance Sheets and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. During the years ended December 31, 2014, 2013, and 2012, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt and forecasted issuances of fixed-rate debt. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings. During the year ended December 31, 2014 the Company recorded a gain of approximately $3,000 from ineffectiveness in earnings attributable to a timing mismatch between the derivative and the hedged item. During the years ended December 31, 2013, and 2012, the Company recorded less than $1,000 of loss from ineffectiveness in earnings attributable to reset date and index mismatches between the derivative and the hedged item, and interest rate swaps with a fair value other than zero at inception of the hedging relationship.
	Amounts reported in Accumulated other comprehensive income/(loss), net in the Consolidated Balance Sheets relate to derivatives that will be reclassified to interest expense as interest payments are made on the Company’s variable-rate debt. Through December 31, 2015, the Company estimates that an additional $5.0 million will be reclassified as an increase to interest expense.
	As of December 31, 2014, the Company had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk (dollars in thousands):
	Interest Rate Derivative		Number of Instruments		Notional
	Interest rate swaps		14		$	365,000
	Interest rate caps		3		$	243,079
	Derivatives not designated as hedges are not speculative and are used to manage the Company’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings and resulted in a gain/(loss) of $(4,000), $271,000, and $290,000 for the years ended December 31, 2014, 2013, and 2012, respectively.
	As of December 31, 2014, the Company had the following outstanding derivatives that were not designated as hedges in qualifying hedging relationships (dollars in thousands):
	Product		Number of Instruments		Notional
	Interest rate caps		1		$	96,409
	Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet
	The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2014 and 2013 (dollars in thousands):
		Asset Derivatives								Liability Derivatives
		(included in Other assets)								(included in Other liabilities)
		Fair Value at:								Fair Value at:
		December 31,				December 31,				December 31,				December 31,
		2014				2013				2014				2013
	Derivatives designated as hedging instruments:
	Interest rate products	$	86			$	—			$	10,368			$	4,965
	Derivatives not designated as hedging instruments:
	Interest rate products	$	2			$	—			$	—			$	—
	Tabular Disclosure of the Effect of Derivative Instruments on the Consolidated Statements of Operations
	The tables below present the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	Derivatives in Cash Flow Hedging Relationships		Unrealized holding gain/(loss) Recognized in OCI												Gain/(Loss) Reclassified from Accumulated OCI into											Gain/(Loss) Recognized in Interest expense
			(Effective Portion)												Interest expense											(Ineffective Portion and Amount Excluded from Effectiveness Testing)
															(Effective Portion)
			Year ended December 31,												Year ended December 31,											Year ended December 31,
			2014				2013				2012				2014				2013				2012			2014		2013		2012
	Interest rate products		$	(8,695	)		$	(469	)		$	(4,924	)		$	(4,834	)		$	(6,851	)		$	(7,649	)	$	3	$	—	$	—
			Gain/(Loss) Recognized in
			Interest and other income/(expense), net
			Year ended December 31,
	Derivatives Not Designated as Hedging Instruments		2014				2013				2012
	Interest rate products		$	(4	)		$	271			$	290
	Credit-risk-related Contingent Features
	The Company has agreements with some of its derivative counterparties that contain a provision where (1) if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then the Company could also be declared in default on its derivative obligations; or (2) the Company could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the Company’s default on the indebtedness.
	Certain of the Company’s agreements with its derivative counterparties contain provisions where if there is a change in the Company’s financial condition that materially changes the Company’s creditworthiness in an adverse manner, the Company may be required to fully collateralize its obligations under the derivative instrument. At December 31, 2014 and 2013, no cash collateral was posted or required to be posted by the Company or by a counterparty.
	The Company also has an agreement with a derivative counterparty that incorporates the loan and financial covenant provisions of the Company’s indebtedness with a lender affiliate of the derivative counterparty. Failure to comply with these covenant provisions would result in the Company being in default on any derivative instrument obligations covered by the agreement.
	The Company has certain agreements with some of its derivative counterparties that contain a provision where, in the event of default by the Company or the counterparty, the right of setoff may be exercised. Any amount payable to one party by the other party may be reduced by its setoff against any amounts payable by the other party. Events that give rise to default by either party may include, but are not limited to, the failure to pay or deliver payment under the derivative contract, the failure to comply with or perform under the derivative agreement, bankruptcy, a merger without assumption of the derivative agreement, or in a merger, a surviving entity's creditworthiness is materially weaker than the original party to the derivative agreement.
	As of December 31, 2014, the fair value of derivatives in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements was $10.6 million. If the Company had breached any of these provisions at December 31, 2014, it would have been required to settle its obligations under the agreements at their termination value of $10.6 million.
	The Company has elected not to offset derivative positions in the consolidated financial statements. The tables below present the effect on its financial position had the Company made the election to offset its derivative positions as of December 31, 2014 and December 31, 2013 (dollars in thousands):
	Offsetting of Derivative Assets
			Gross Amounts of Recognized Assets				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets								Net Amount
															Financial Instruments				Cash Collateral Received
	December 31, 2014		$	88			$	—			$	88			$	(27	)		$	—			$	61
	December 31, 2013		$	—			$	—			$	—			$	—			$	—			$	—
	(a) Amounts reconcile to the aggregate fair value of derivative assets in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.
	Offsetting of Derivative Liabilities
			Gross Amounts of Recognized Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Liabilities Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets								Net Amount
															Financial Instruments				Cash Collateral Posted
	December 31, 2014		$	10,368			$	—			$	10,368			$	(27	)		$	—			$	10,341
	December 31, 2013		$	4,965			$	—			$	4,965			$	—			$	—			$	4,965
	(a) Amounts reconcile to the aggregate fair value of derivative liabilities in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.
United Dominion Reality L.P.
Entity Information [Line Items]
DERIVATIVES AND HEDGING ACTIVITY	DERIVATIVES AND HEDGING ACTIVITY
	Risk Management Objective of Using Derivatives
	The Operating Partnership is exposed to certain risks arising from both its business operations and economic conditions. The General Partner principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The General Partner manages economic risks, including interest rate, liquidity, and credit risk primarily by managing the amount, sources, and duration of its debt funding and through the use of derivative financial instruments. Specifically, the General Partner enters into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The General Partner’s and the Operating Partnership’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the General Partner’s known or expected cash payments principally related to the General Partner’s borrowings.
	Cash Flow Hedges of Interest Rate Risk
	The General Partner’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the General Partner primarily uses interest rate swaps and caps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the General Partner making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Interest rate caps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty if interest rates rise above the strike rate on the contract in exchange for an up front premium.
	A portion of the General Partner’s interest rate derivatives have been allocated to the Operating Partnership based on the General Partner’s underlying debt instruments allocated to the Operating Partnership. (See Note 5, Debt.)
	The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in Accumulated other comprehensive loss in the Consolidated Balance Sheets, and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. During the years ended December 31, 2014, 2013, and 2012, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt and forecasted issuances of fixed-rate debt. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings. During the years ended December 31, 2014, 2013, and 2012, the Operating Partnership recorded less than $1,000 of ineffectiveness in earnings attributable to reset date and index mismatches between the derivative and the hedged item.
	Amounts reported in Accumulated other comprehensive loss related to derivatives will be reclassified to interest expense as interest payments are made on the General Partner’s variable-rate debt that is allocated to the Operating Partnership. During the next twelve months through December 31, 2015, we estimate that an additional $946,000 will be reclassified as an increase to interest expense.
	As of December 31, 2014, the Operating Partnership had the following outstanding interest rate derivatives designated as cash flow hedges of interest rate risk (dollars in thousands):
	Interest Rate Derivative		Number of Instruments		Notional
	Interest rate swaps		1		$	46,272
	Interest rate caps		2		$	166,341
	Derivatives not designated as hedges are not speculative and are used to manage the Operating Partnership’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings and resulted in losses of $3,000, $9,000, and $9,000 for the years ended December 31, 2014, 2013, and 2012, respectively.
	As of December 31, 2014, we had the following outstanding derivatives that were not designated as hedges in qualifying hedging relationships (dollars in thousands):
	Product		Number of Instruments		Notional
	Interest rate caps		1		$	89,220
	Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet
	The table below presents the fair value of the Operating Partnership’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2014 and 2013 (dollars in thousands):
		Asset Derivatives								Liability Derivatives
		(included in Other assets)								(Included in Other liabilities)
		Fair Value at:								Fair Value at:
		December 31,				December 31,				December 31,				December 31,
		2014				2013				2014				2013
	Derivatives designated as hedging instruments:
	Interest rate products	$	37			$	—			$	918			$	2,731
	Derivatives not designated as hedging instruments:
	Interest rate products	$	2			$	—			$	—			$	—
	Tabular Disclosure of the Effect of Derivative Instruments on the Consolidated Statements of Operations
	The tables below present the effect of the derivative financial instruments on the Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	Derivatives in Cash Flow Hedging Relationships		Unrealized holding gain/(loss) Recognized in OCI										Gain/(Loss) Reclassified from Accumulated OCI into
			(Effective Portion)										Interest expense
													(Effective Portion)
			Year ended December 31,										Year ended December 31,
			2014				2013				2012		2014				2013				2012
	Interest rate products		$	(285	)		$	(348	)		($1,898)		$	(2,275	)		$	(2,652	)		$	(3,431	)
	Derivatives Not Designated as Hedging Instruments		Gain/(Loss) Recognized in
			Interest and other income/(expense), net
			Year ended December 31,
			2014				2013				2012
	Interest rate products		$	(3	)		$	(9	)		$	(9	)
	Credit-risk-related Contingent Features
	The General Partner has agreements with some of its derivative counterparties that contain a provision where (1) if the General Partner defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then the General Partner could also be declared in default on its derivative obligations; or (2) the General Partner could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the General Partner’s default on the indebtedness.
	Certain of the General Partner’s agreements with its derivative counterparties contain provisions where if there is a change in the General Partner’s financial condition that materially changes the General Partner’s creditworthiness in an adverse manner, the General Partner may be required to fully collateralize its obligations under the derivative instrument. At December 31, 2014 and 2013, no cash collateral was posted or required to be posted by the General Partner or by a counterparty.
	The General Partner also has an agreement with a derivative counterparty that incorporates the loan and financial covenant provisions of the General Partner’s indebtedness with a lender affiliate of the derivative counterparty. Failure to comply with these covenant provisions would result in the General Partner being in default on any derivative instrument obligations covered by the agreement.
	As of December 31, 2014, the fair value of derivatives in a net liability position that were allocated to the Operating Partnership, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements was $969,000. If the General Partner had breached any of these provisions at December 31, 2014, it would have been required to settle its obligations under the agreements at their termination value of $969,000.
	The General Partner has elected not to offset derivative positions in the consolidated financial statements. The table below presents the effect on the Operating Partnership's financial position had the General Partner made the election to offset its derivative positions as of December 31, 2014 and December 31, 2013:
	Offsetting of Derivative Assets
															Gross Amounts Not Offset in the Consolidated Balance Sheets
			Gross Amounts of Recognized Assets				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)				Financial Instruments				Cash Collateral Received				Net Amount
	December 31, 2014		$	39			$	—			$	39			$	—			$	—			$	39
	December 31, 2013		$	—			$	—			$	—			$	—			$	—			$	—
	(a) Amounts reconcile to the aggregate fair value of derivative assets in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.
	Offsetting of Derivative Liabilities
															Gross Amounts Not Offset in the Consolidated Balance Sheets
			Gross Amounts of Recognized Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Liabilities Presented in the Consolidated Balance Sheets (b)				Financial Instruments				Cash Collateral Posted				Net Amount
	December 31, 2014		$	918			$	—			$	918			$	—			$	—			$	918
	December 31, 2013		$	2,731			$	—			$	2,731			$	—			$	—			$	2,731
	(b) Amounts reconcile to the aggregate fair value of derivative liabilities in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.

Capital_Structure_UNITED_DOMIN

Capital Structure (UNITED DOMINION REALTY, L.P.) (United Dominion Reality L.P.)	12 Months Ended
	Dec. 31, 2014
United Dominion Reality L.P.
Entity Information [Line Items]
CAPITAL STRUCTURE	CAPITAL STRUCTURE
	General Partnership Units
	The General Partner has complete discretion to manage and control the operations and business of the Operating Partnership, which includes but is not limited to the acquisition and disposition of real property, construction of buildings and making capital improvements, and the borrowing of funds from outside lenders or UDR and its subsidiaries to finance such activities. The General Partner can generally authorize, issue, sell, redeem or purchase any OP Unit or securities of the Operating Partnership without the approval of the limited partners. The General Partner can also approve, with regard to the issuances of OP Units, the class or one or more series of classes, with designations, preferences, participating, optional or other special rights, powers and duties including rights, powers and duties senior to limited partnership interests without approval of any limited partners except holders of Class A Limited Partnership Units. There were 110,883 General Partnership units outstanding at December 31, 2014 and 2013, all of which were held by UDR.
	Limited Partnership Units
	At December 31, 2014 and 2013, there were 183,167,815 limited partnership units outstanding, of which 1,873,332 were Class A Limited Partnership Units. UDR owned 174,002,342 limited partnership units or 95.0% and 173,848,891 limited partnership units or 94.9% at December 31, 2014 and 2013, respectively. The remaining 9,165,473 or 5.0% and 9,318,924 or 5.1% OP Units outstanding were held by non-affiliated partners at December 31, 2014 and 2013, respectively, of which 1,751,671 were Class A Limited Partnership Units.
	Subject to the terms of the Operating Partnership Agreement, the limited partners have the right to require the Operating Partnership to redeem all or a portion of the OP Units held by the limited partner at a redemption price equal to and in the form of the Cash Amount (as defined in the Operating Partnership Agreement), provided that such OP Units have been outstanding for at least one year. UDR, as general partner of the Operating Partnership, may, in its sole discretion, purchase the OP Units by paying to the limited partner either the Cash Amount or the REIT Share Amount (generally one share of common stock of UDR for each OP Unit), as defined in the Operating Partnership Agreement.
	The non-affiliated limited partners’ capital is adjusted to redemption value at the end of each reporting period with the corresponding offset against UDR’s limited partner capital account based on the redemption rights noted above. The aggregate value upon redemption of the then-outstanding OP Units held by limited partners was $282.5 million and $217.6 million as of December 31, 2014 and December 31, 2013, respectively, based on the value of UDR’s common stock at each period end. A limited partner has no right to receive any distributions from the Operating Partnership on or after the date of redemption of its OP Units.
	Class A Limited Partnership Units
	Class A Limited Partnership Units have a cumulative, annual, non-compounded preferred return, which is equal to 8% based on a value of $16.61 per Class A Limited Partnership Unit.
	Holders of the Class A Limited Partnership Units exclusively possess certain voting rights. The Operating Partnership may not do the following without approval of the holders of the Class A Limited Partnership Units: (i) increase the authorized or issued amount of Class A Limited Partnership Units, (ii) reclassify any other partnership interest into Class A Limited Partnership Units, (iii) create, authorize or issue any obligations or security convertible into or the right to purchase any Class of Limited Partnership units, without the approval of the holders of the Class A Limited Partnership Units, (iv) enter into a merger or acquisition, or (v) amend or modify the Agreement of Limited Partnership of the Operating Partnership in a manner that adversely affects the relative rights, preferences or privileges of the Class A Limited Partnership Units.
	The following table shows OP Units outstanding and OP Unit activity as of and for the years ended December 31, 2014, 2013, and 2012:
					UDR, Inc.
		Class A Limited	Limited		Limited		General	Total
		Partner	Partners		Partner		Partner
	Ending balance at December 31, 2011	1,751,671	7,669,632		174,749,068		110,883	184,281,254
	OP redemptions for cash	—	(5,646	)	5,646		—	—
	OP redemptions for UDR stock	—	(20,438	)	20,438		—	—
	Ending balance at December 31, 2012	1,751,671	7,643,548		174,775,152		110,883	184,281,254
	OP Units redeemed for the distribution of real estate to the General partner (a)	—	—		(1,002,556	)	—	(1,002,556	)
	OP redemptions for UDR stock	—	(76,295	)	76,295		—	—
	Ending balance at December 31, 2013	1,751,671	7,567,253		173,848,891		110,883	183,278,698
	OP redemptions for UDR stock	—	(153,451	)	153,451		—	—
	Ending balance at December 31, 2014	1,751,671	7,413,802		174,002,342		110,883	183,278,698
	(a) In November 2013, the Operating Partnership distributed the development property Los Alisos to the General Partner as a capital distribution. Upon the distribution of the property, the Operating Partnership redeemed 1,002,556 limited partnership units owned by UDR and affiliated entities, resulting in a capital reduction of $23.3 million.
	Allocation of Profits and Losses
	Profit of the Operating Partnership is allocated in the following order: (i) to the General Partner and the Limited Partners in proportion to and up to the amount of cash distributions made during the year, and (ii) to the General Partner and Limited Partners in accordance with their percentage interests. Losses and depreciation and amortization expenses, non-recourse liabilities are allocated to the General Partner and Limited Partners in accordance with their percentage interests. Losses allocated to the Limited Partners are capped to the extent that such an allocation would not cause a deficit in the Limited Partners capital account. Such losses are, therefore, allocated to the General Partner. If any Partner’s capital balance were to fall into a deficit any income and gains are allocated to each Partner sufficient to eliminate its negative capital balance.

Commitments_and_Contingencies_

Commitments and Contingencies (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES
	Commitments
	Real Estate Under Development
	The following summarizes the Company’s real estate commitments at December 31, 2014 (dollars in thousands):
		Number of		Costs Incurred				Expected Costs			Average Ownership
		Properties		to Date (a)				to Complete (unaudited)			Stake
	Wholly-owned — under development	1		$	177,632		(b)	$	40,068		100	%
	Wholly-owned — redevelopment	1		83,778			(b)	14,222			100	%
	Joint ventures:
	Unconsolidated joint ventures	3		225,013				172,155		(c)	Various
	Participating loan investments	1		62,707			(d)	29,302		(e)	0	%
	Total			$	549,130			$	255,747
	(a) Represents 100% of project costs incurred to date.
	(b) Costs incurred to date include $14.7 million and $1.8 million of accrued fixed assets for development and redevelopment, respectively.
	(c) Represents UDR’s contributed and remaining equity commitment in unconsolidated joint ventures.
	(d) Represents the participating loan balance funded as of December 31, 2014.
	(e) Represents UDR’s remaining participating loan commitment for Steele Creek.
	Ground and Other Leases
	UDR owns six communities which are subject to ground leases expiring between 2019 and 2103. In addition, UDR is a lessee to various operating leases related to office space rented by the Company with expiration dates through 2016. Future minimum lease payments as of December 31, 2014 are as follows (dollars in thousands):
		Ground				Office Space
		Leases (a)
	2015	$	5,412			$	709
	2016	5,412				124
	2017	5,412				76
	2018	5,412				76
	2019	5,412				76
	Thereafter	313,735				109
	Total	$	340,795			$	1,170
	(a)	For purposes of our ground lease contracts, the Company uses the minimum lease payment, if stated in the agreement. For ground lease agreements where there is a reset provision based on the communities appraised value or consumer price index but does not include a specified minimum lease payment, the Company uses the current rent over the remainder of the lease term.
	UDR incurred $5.4 million, $5.2 million, $5.1 million of ground rent expense for the years ended December 31, 2014, 2013, and 2012, respectively. These costs are reported within the line item Other Operating Expenses on the Consolidated Statements of Operations. The Company incurred $1.3 million, $1.3 million, $1.1 million of rent expense related to office space for the years ended December 31, 2014, 2013, and 2012, respectively. These costs are included in General and Administrative on the Consolidated Statements of Operations. In February 2015, the Company acquired the office building in Highlands Ranch, Colorado, which housed its corporate offices it had previously leased. See Note 4, Real Estate Owned, for additional details.
	Contingencies
	Litigation and Legal Matters
	The Company is subject to various legal proceedings and claims arising in the ordinary course of business. The Company cannot determine the ultimate liability with respect to such legal proceedings and claims at this time. The Company believes that such liability, to the extent not provided for through insurance or otherwise, will not have a material adverse effect on our financial condition, results of operations or cash flow.
United Dominion Reality L.P.
Entity Information [Line Items]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES
	Commitments
	Ground Leases
	The Operating Partnership owns five communities, which are subject to ground leases expiring between 2019 and 2103. Future minimum lease payments as of December 31, 2014 are $5.3 million for each of the years ending December 31, 2014 to 2018, and a total of $313.6 million for years thereafter. For purposes of our ground lease contracts, the Operating Partnership uses the minimum lease payment, if stated in the agreement. For ground lease agreements where there is a reset provision based on the communities appraised value or consumer price index but does not include a specified minimum lease payment, the Operating Partnership uses the current rent over the remainder of the lease term.
	The Operating Partnership incurred $5.3 million, $5.1 million, and $5.0 million of ground rent expense for the years ended December 31, 2014, 2013, and 2012, respectively.
	Contingencies
	Litigation and Legal Matters
	The Operating Partnership is subject to various legal proceedings and claims arising in the ordinary course of business. The Operating Partnership cannot determine the ultimate liability with respect to such legal proceedings and claims at this time. The General Partner believes that such liability, to the extent not provided for through insurance or otherwise, will not have a material adverse effect on the Operating Partnership’s financial condition, results of operations or cash flow.

Reportable_Segments_UNITED_DOM

Reportable Segments (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
REPORTABLE SEGMENTS	REPORTABLE SEGMENTS
	GAAP guidance requires that segment disclosures present the measure(s) used by the chief operating decision maker to decide how to allocate resources and for purposes of assessing such segments’ performance. UDR’s chief operating decision maker is comprised of several members of its executive management team who use several generally accepted industry financial measures to assess the performance of the business for our reportable operating segments.
	UDR owns and operates multifamily apartment communities that generate rental and other property related income through the leasing of apartment homes to a diverse base of tenants. The primary financial measures for UDR’s apartment communities are rental income and NOI. Rental income represents gross market rent less adjustments for concessions, vacancy loss and bad debt. NOI is defined as rental income less direct property rental expenses. Rental expenses include real estate taxes, insurance, personnel, utilities, repairs and maintenance, administrative and marketing. Excluded from NOI is property management expense which is calculated as 2.75% of property revenue to cover the regional supervision and accounting costs related to consolidated property operations, and land rent. UDR’s chief operating decision maker utilizes NOI as the key measure of segment profit or loss.
	UDR’s two reportable segments are Same-Store Communities and Non-Mature Communities/Other:
	•	Same-Store Communities represent those communities acquired, developed, and stabilized prior to January 1, 2013 and held as of December 31, 2014. A comparison of operating results from the prior year is meaningful as these communities were owned and had stabilized occupancy and operating expenses as of the beginning of the prior year, there is no plan to conduct substantial redevelopment activities, and the community is not held for disposition within the current year. A community is considered to have stabilized occupancy once it achieves 90% occupancy for at least three consecutive months.
	•	Non-Mature Communities/Other represent those communities that do not meet the criteria to be included in Same-Store Communities, including, but not limited to, recently acquired, developed and redeveloped communities, and the non-apartment components of mixed use properties.
	Management evaluates the performance of each of our apartment communities on a Same-Store Community and Non-Mature Community/Other basis, as well as individually and geographically. This is consistent with the aggregation criteria under GAAP as each of our apartment communities generally has similar economic characteristics, facilities, services, and tenants. Therefore, the Company’s reportable segments have been aggregated by geography in a manner identical to that which is provided to the chief operating decision maker.
	All revenues are from external customers and no single tenant or related group of tenants contributed 10% or more of UDR’s total revenues during the years ended December 31, 2014, 2013, and 2012.
	The following table details rental income and NOI from continuing and discontinued operations for UDR’s reportable segments for the years ended December 31, 2014, 2013, and 2012, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. in the Consolidated Statements of Operations (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Reportable apartment home segment rental income
	Same-Store Communities
	West Region	$	245,803		$	231,156		$	218,268
	Mid-Atlantic Region	161,566			160,208			155,777
	Southeast Region	107,991			102,988			97,699
	Northeast Region	60,796			58,075			54,461
	Southwest Region	54,810			52,302			46,800
	Non-Mature Communities/Other	174,183			150,907			171,239
	Total segment and consolidated rental income	$	805,149		$	755,636		$	744,244
	Reportable apartment home segment NOI
	Same-Store Communities
	West Region	$	178,926		$	166,033		$	154,205
	Mid-Atlantic Region	111,762			111,643			108,490
	Southeast Region	71,528			67,264			63,122
	Northeast Region	44,897			42,350			39,377
	Southwest Region	33,725			31,927			27,878
	Non-Mature Communities/Other	115,483			94,824			111,128
	Total segment and consolidated NOI	556,321			514,041			504,200
	Reconciling items:
	Joint venture management and other fees	13,044			12,442			11,911
	Property management	(22,142		)	(20,780		)	(20,465		)
	Other operating expenses	(8,271		)	(7,136		)	(5,718		)
	Real estate depreciation and amortization	(358,154		)	(341,490		)	(350,401		)
	General and administrative	(47,800		)	(42,238		)	(43,792		)
	Casualty-related recoveries/(charges), net	(541		)	12,253			(8,495		)
	Other depreciation and amortization	(5,775		)	(6,741		)	(4,105		)
	Income/(loss) from unconsolidated entities	(7,006		)	(415		)	(8,579		)
	Interest expense	(130,454		)	(126,083		)	(138,792		)
	Interest and other income/(expense), net	11,837			4,681			2,703
	Tax benefit/(provision), net	15,136			7,299			30,282
	Gain/(loss) on sale of real estate owned, net of tax	143,647			40,449			251,554
	Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)	(1,530		)	(7,986		)
	Net (income)/loss attributable to noncontrolling interests	3			60			(140		)
	Net income/(loss) attributable to UDR, Inc.	$	154,334		$	44,812		$	212,177
	The following table details the assets of UDR’s reportable segments as of December 31, 2014 and 2013 (dollars in thousands):
		December 31,			December 31,
		2014			2013
	Reportable apartment home segment assets:
	Same-Store communities:
	West Region	$	2,358,444		$	2,337,980
	Mid-Atlantic Region	1,410,156			1,395,772
	Southeast Region	786,438			785,134
	Northeast Region	746,550			738,805
	Southwest Region	440,721			434,875
	Non-mature Communities/Other	2,640,950			2,515,411
	Total segment assets	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Total segment assets — net book value	5,948,487			5,999,183
	Reconciling items:
	Cash and cash equivalents	15,224			30,249
	Restricted cash	22,340			22,796
	Deferred financing costs, net	22,686			26,924
	Notes receivable, net	14,369			83,033
Investment in and advances to unconsolidated joint ventures, net	718,226			507,655
Other assets	105,202			137,882
Total consolidated assets	$	6,846,534		$	6,807,722
Capital expenditures related to our Same-Store Communities totaled $55.3 million, $47.5 million, and $46.4 million for the years ended December 31, 2014, 2013, and 2012, respectively. Capital expenditures related to our Non-Mature Communities/Other totaled $8.1 million, $8.3 million, and $8.7 million for the years ended December 31, 2014, 2013, and 2012, respectively.
Markets included in the above geographic segments are as follows:
i.	West Region — Orange County, San Francisco, Seattle, Monterey Peninsula, Los Angeles, Other Southern California, and Portland
ii.	Mid-Atlantic Region — Metropolitan D.C., Baltimore, Richmond, Norfolk, and Other Mid-Atlantic
iii.	Southeast Region — Tampa, Orlando, Nashville, and Other Florida
iv.	Northeast Region — New York and Boston
v.	Southwest Region — Dallas and Austin
United Dominion Reality L.P.
Entity Information [Line Items]
REPORTABLE SEGMENTS	REPORTABLE SEGMENTS
	GAAP guidance requires that segment disclosures present the measure(s) used by the chief operating decision maker to decide how to allocate resources and for purposes of assessing such segments’ performance. The Operating Partnership has the same chief operating decision maker as that of its parent, the General Partner. The chief operating decision maker consists of several members of UDR’s executive management team who use several generally accepted industry financial measures to assess the performance of the business for our reportable operating segments.
	The Operating Partnership owns and operates multifamily apartment communities throughout the United States that generate rental and other property related income through the leasing of apartment homes to a diverse base of tenants. The primary financial measures of the Operating Partnership’s apartment communities are rental income and NOI, and are included in the chief operating decision maker’s assessment of UDR’s performance on a consolidated basis. Rental income represents gross market rent less adjustments for concessions, vacancy loss and bad debt. NOI is defined as total revenues less direct property operating expenses. Rental expenses include real estate taxes, insurance, personnel, utilities, repairs and maintenance, administrative and marketing. Excluded from NOI is property management expense, which is calculated as 2.75% of property revenue to cover the regional supervision and accounting costs related to consolidated property operations and land rent. The chief operating decision maker of the General Partner utilizes NOI as the key measure of segment profit or loss.
	The Operating Partnership’s two reportable segments are Same-Store Communities and Non-Mature/Other communities:
	•	Same-Store Communities represent those communities acquired, developed, and stabilized prior to January 1, 2013 and held as of December 31, 2014. A comparison of operating results from the prior year is meaningful as these communities were owned and had stabilized occupancy and operating expenses as of the beginning of the prior year, there is no plan to conduct substantial redevelopment activities, and the communities are not held for disposition within the current year. A community is considered to have stabilized occupancy once it achieves 90% occupancy for at least three consecutive months.
	•	Non-Mature Communities/Other represent those communities that do not meet the criteria to be included in Same-Store Communities, including, but not limited to, recently acquired, developed and redeveloped communities, and the non-apartment components of mixed use properties.
	Management of the General Partner evaluates the performance of each of the Operating Partnership's apartment communities on a Same-Store Community and Non-Mature Community/Other basis, as well as individually and geographically. This is consistent with the aggregation criteria under GAAP as each of our apartment communities generally has similar economic characteristics, facilities, services, and tenants. Therefore, the Operating Partnership’s reportable segments have been aggregated by geography in a manner identical to that which is provided to the chief operating decision maker.
	All revenues are from external customers and no single tenant or related group of tenants contributed 10% or more of the Operating Partnership’s total revenues during the years ended December 31, 2014, 2013, and 2012.
	The following table details rental income and NOI from continuing and discontinued operations for the Operating Partnership’s reportable segments for the years ended December 31, 2014, 2013, and 2012, and reconciles NOI to Net income/(loss) attributable to OP unitholders in the Consolidated Statements of Operations (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Reportable apartment home segment rental income
	Same-Store Communities
	West Region	$	194,105		$	181,935		$	172,096
	Mid-Atlantic Region	68,822			68,205			66,487
	Northeast Region	38,087			36,623			34,579
	Southeast Region	45,224			43,208			40,771
	Southwest Region	26,580			25,614			23,980
	Non-Mature Communities/Other	49,816			55,257			62,778
	Total segment and consolidated rental income	$	422,634		$	410,842		$	400,691
	Reportable apartment home segment NOI
	Same-Store Communities
	West Region	$	142,388		$	131,276		$	122,477
	Mid-Atlantic Region	46,639			46,770			45,801
	Northeast Region	28,930			27,149			25,653
	Southeast Region	29,815			28,105			26,510
	Southwest Region	16,821			16,057			14,738
	Non-Mature Communities/Other	35,720			38,178			46,359
	Total segment and consolidated NOI	300,313			287,535			281,538
	Reconciling items:
	Property management	(11,622		)	(11,298		)	(11,019		)
	Other operating expenses	(5,172		)	(5,728		)	(5,272		)
	Real estate depreciation and amortization	(179,176		)	(181,302		)	(195,051		)
	General and administrative	(28,541		)	(24,808		)	(26,204		)
	Casualty-related recoveries/(charges), net	(541		)	8,083			(5,518		)
	Interest expense	(41,717		)	(36,058		)	(45,234		)
	Gain/(loss) on sale of real estate owned, net of tax	63,635			41,518			51,094
	Net income/(loss) attributable to noncontrolling interests	(952		)	(4,566		)	(352		)
	Net income/(loss) attributable to OP unitholders	$	96,227		$	73,376		$	43,982
	The following table details the assets of the Operating Partnership’s reportable segments as of December 31, 2014 and 2013 (dollars in thousands):
		December 31,			December 31, 2013
		2014
	Reportable apartment home segment assets
	Same-Store Communities
	West Region	$	1,749,494		$	1,733,144
	Mid-Atlantic Region	713,093			706,447
	Northeast Region	447,269			443,483
	Southeast Region	333,428			328,150
	Southwest Region	228,996			226,252
	Non-Mature Communities/Other	766,490			751,004
	Total segment assets	4,238,770			4,188,480
	Accumulated depreciation	(1,403,303		)	(1,241,574		)
	Total segment assets - net book value	2,835,467			2,946,906
	Reconciling items:
	Cash and cash equivalents	502			1,897
	Restricted cash	13,811			13,526
	Deferred financing costs, net	4,475			5,848
	Other assets	24,029			25,064
	Total consolidated assets	$	2,878,284		$	2,993,241
	Capital expenditures related to the Operating Partnership’s Same-Store Communities totaled $32.8 million and $25.8 million for the years ended December 31, 2014 and 2013, respectively. Capital expenditures related to the Operating Partnership’s Non-Mature Communities/Other totaled $1.0 million and $2.0 million for the years ended December 31, 2014 and 2013, respectively.
	Markets included in the above geographic segments are as follows:
	i.	West Region — Orange County, San Francisco, Monterey Peninsula, Los Angeles, Seattle, Inland Empire, Portland, and San Diego
	ii.	Mid-Atlantic Region — Metropolitan, D.C. and Baltimore
	iii.	Northeast Region — New York and Boston
iv.	Southeast Region — Nashville, Tampa, and Other Florida
v.	Southwest Region — Dallas

Hurricane_Related_Charges_UNIT

Hurricane Related Charges (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Hurricane Related Charges	-RELATED (RECOVERIES)/CHARGES
	In October 2012, Hurricane Sandy hit the East Coast, affecting three of the Company’s operating communities (1,706 apartment homes) located in New York City. The properties suffered some physical damage, and were closed to residents for a period following the hurricane. The Company has insurance policies that provide coverage for property damage and business interruption, subject to applicable retention.
	Based on the claims filed and management’s estimates, the Company recognized a $9.0 million impairment charge for the damaged assets’ net book value and incurred $10.4 million of repair and cleanup costs during the year ended December 31, 2012. The impairment charge and the repair and cleanup costs incurred were reduced as of December 31, 2012 by $14.5 million of estimated insurance recovery, and were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations. During the year ended December 31, 2013, no material adjustments to the impairment charge and the repair and cleanup costs incurred were recognized. With the exception of one of the properties that is under redevelopment at December 31, 2013, the rehabilitation of the remaining two properties was substantially completed as of December 31, 2013 and was completed during 2014.
	As of December 31, 2013, the Company had settled the Hurricane Sandy claims and received insurance proceeds in excess of the $14.5 million estimated insurance recovery receivable related to the impairment charge and the repair and cleanup costs incurred. As a result, the Company recognized a Casualty-related recovery of approximately $4.8 million and a casualty gain of approximately $654,000 for the year ended December 31, 2013. Both the recovery and casualty gain were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations.
	Based on the claims filed and management’s estimates, the Company recognized $4.4 million of business interruption losses for the year ended December 31, 2012, of which $3.6 million were related to rent concession rebates provided to residents during the period the properties were uninhabitable and were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations, and $767,000 were related to rent that was not contractually receivable and were classified as a reduction to Rental income on the Consolidated Statements of Operations. As noted below, the Company recovered from the insurance carrier approximately $4.2 million of the $4.4 million of 2012 business interruption losses. The Company estimates that it incurred an additional $3.4 million of business interruption losses for the year ended December 31, 2013. As noted below, the Company recovered from the insurance carrier approximately $2.6 million of the $3.4 million of 2013 business interruption losses.
	During the year ended December 31, 2013, the Company received approximately $6.8 million of insurance proceeds for recovery of business interruption losses. Of the $6.8 million of insurance proceeds received in 2013, $4.2 million related to recovery of business interruption losses incurred in 2012 and the remaining $2.6 million related to recovery of business interruption losses incurred in 2013. The $6.8 million of recovery was classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations as of December 31, 2013.
	During the year ended December 31, 2014, the Company recorded $541,000 of casualty-related losses due to property damage incurred during an earthquake and a storm in California, all of which are included in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations.
United Dominion Reality L.P.
Entity Information [Line Items]
Hurricane Related Charges	-RELATED (RECOVERIES)/CHARGES
	In October 2012, Hurricane Sandy hit the East Coast, affecting two of the Operating Partnership’s operating communities (1,001 apartment homes) located in New York City. The properties suffered some physical damage, and were closed to residents for a period following the hurricane. The Operating Partnership has insurance policies that provide coverage for property damage and business interruption, subject to applicable retention.
	Based on the claims filed and management’s estimates, the Operating Partnership recognized a $7.1 million impairment charge for the damaged assets’ net book value and incurred $7.0 million of repair and cleanup costs during the year ended December 31, 2012. The impairment charge and the repair and cleanup costs incurred were reduced as of December 31, 2012 by $10.8 million of estimated insurance recovery, and were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations. During the year ended December 31, 2013, no material adjustments to the impairment charge and the repair and cleanup costs incurred were recognized. The rehabilitation of these two properties was substantially completed as of December 31, 2013.
	As of December 31, 2013, the Operating Partnership had settled the Hurricane Sandy claims and received insurance proceeds in excess of the $10.8 million estimated insurance recovery receivable related to the impairment charge and the repair and cleanup costs incurred. As a result, the Operating Partnership recognized a Casualty-related recovery of approximately $3.3 million and a casualty gain of approximately $582,000 for the year ended December 31, 2013. Both the recovery and casualty gain were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations.
	Based on the claims filed and management’s estimates, the Operating Partnership recognized $2.2 million of business interruption losses for the year ended December 31, 2012, of which $1.8 million were related to rent concession rebates provided to residents during the period the properties were uninhabitable and were classified in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations, and $400,000 were related to rent that was not contractually receivable and were classified as a reduction to Rental income on the Consolidated Statements of Operations. The Operating Partnership estimates that it incurred an additional $2.1 million of business interruption losses for the year ended December 31, 2013. As noted, the Operating Partnership settled the Hurricane Sandy claims as of December 31, 2013.
	During the year ended December 31, 2013, the Operating Partnership received approximately $4.2 million of insurance proceeds for recovery of business interruption losses. Of the $4.2 million of insurance proceeds received during the year ended December 31, 2013, $2.1 million related to recovery of business interruption losses incurred in 2012 and the remaining $2.1 million related to recovery of business interruption losses incurred in 2013. The $4.2 million of recovery was included in Casualty-related (recoveries)/charges, net on the Consolidated Statements of Operations.

Unaudited_Summarized_Consolida1

Unaudited Summarized Consolidated Quarterly Financial Data (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
UNAUDITED SUMMARIZED CONSOLIDATED QUARTERLY FINANCIAL DATA	UNAUDITED SUMMARIZED CONSOLIDATED QUARTERLY FINANCIAL DATA
	Selected consolidated quarterly financial data for the three and twelve months ended December 31, 2014 and 2013 is summarized in the table below (dollars in thousands, except per share amounts):
		Three Months Ended
		March 31,			June 30,		September 30,		December 31,
	2014
	Rental income (a)	$	194,352		$	200,959	$	203,587	$	206,104
	Income/(loss) from continuing operations	(5,195		)	4,359		10,611		6,485
	Income/(loss) from discontinued operations, net of tax	(87		)	18		79		—
	Net income/(loss) attributable to common stockholders	17,430			29,076		39,618		64,486
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	0.07		$	0.12	$	0.16	$	0.25
	Weighted average number of shares outstanding
	Basic	250,177			250,255		251,655		253,983
	Diluted	251,822			252,191		253,732		256,000
	2013
	Rental income (a)	$	181,961		$	186,285	$	187,917	$	190,321
	Income/(loss) from continuing operations	(1,162		)	4,525		2,351		(3,374		)
	Income/(loss) from discontinued operations, net of tax	853			829		884		41,376
	Net income/(loss) attributable to common stockholders	(1,199		)	4,261		2,257		35,769
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	(0.00	)	$	0.02	$	0.01	$	0.14
	Weighted average number of shares outstanding
	Basic	249,917			249,985		249,985		249,987
	Diluted	249,917			251,406		251,454		249,987
	(a)	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
	(b)	Quarterly income/(loss) per share amounts may not total to the annual amounts.
United Dominion Reality L.P.
Entity Information [Line Items]
UNAUDITED SUMMARIZED CONSOLIDATED QUARTERLY FINANCIAL DATA	UNAUDITED SUMMARIZED CONSOLIDATED QUARTERLY FINANCIAL DATA
	Selected consolidated quarterly financial data for the years ended December 31, 2014 and 2013 is summarized in the table blow (dollars in thousands, except per share amounts):
		Three Months Ended
		March 31,			June 30,		September 30,		December 31,
	2014
	Rental income (a)	$	102,370		$	104,842	$	107,444	$	107,978
	Income/(loss) from continuing operations	6,411			8,319		8,875		9,939
	Income/(loss) attributable to OP unitholders	30,533			24,426		8,637		32,631
	Income/(loss) attributable to OP unitholders per weighted average OP Unit — basic and diluted (b)	$	0.17		$	0.13	$	0.05	$	0.18
	2013
	Rental income (a)	$	97,770		$	100,421	$	101,558	$	102,104
	Income/(loss) from continuing operations	6,870			9,339		10,069		6,488
	Income/(loss) from discontinued operations	905			882		982		42,407
	Income/(loss) attributable to OP unitholders	7,729			10,154		11,011		44,482
	Income/(loss) attributable to OP unitholders per weighted average OP Unit — basic and diluted (b)	$	0.04		$	0.06	$	0.06	$	0.24
	(a)	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
	(b)	Quarterly income/(loss) per OP Unit amounts may not total to the annual amounts.

Schedule_III_Real_Estate_Owned

Schedule - III Real Estate Owned	12 Months Ended
	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Schedule III - Real Estate Owned
					Initial Costs										Gross Amount at Which Carried at Close of Period
		Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
					Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
					Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
	WEST REGION
	Harbor at Mesa Verde	$	50,358		$	20,476		$	28,538		$	49,014	$	12,949	$	21,058	$	40,905	$	61,963	$	26,242	2003	3-Jun
	27 Seventy Five Mesa Verde	30,660			99,329			110,644			209,973		91,693		112,333		189,333		301,666		72,689		1972/2013	4-Oct
	Pacific Shores	34,112			7,345			22,624			29,969		9,150		7,759		31,360		39,119		19,665		2003	3-Jun
	Huntington Vista	27,972			8,055			22,486			30,541		7,637		8,438		29,740		38,178		18,655		1970	3-Jun
	Missions at Back Bay	—			229			14,129			14,358		2,133		10,802		5,689		16,491		3,994		1969	3-Dec
	Coronado at Newport — North	—			62,516			46,082			108,598		24,693		66,756		66,535		133,291		41,982		2000	4-Oct
	Huntington Villas	50,771			61,535			18,017			79,552		7,132		62,223		24,461		86,684		16,061		1972	4-Sep
	Vista Del Rey	—			10,670			7,080			17,750		2,062		10,830		8,982		19,812		5,769		1969	4-Sep
	Foxborough	—			12,071			6,187			18,258		2,749		12,366		8,641		21,007		5,119		1969	4-Sep
	Coronado South	—			58,785			50,067			108,852		17,875		59,277		67,450		126,727		40,783		2000	5-Mar
	1818 Platinum Triangle	—			16,663			51,905			68,568		470		16,693		52,345		69,038		13,682		2009	10-Aug
	Beach & Ocean	—			12,878			—			12,878		38,160		13,007		38,031		51,038		347		2014	11-Aug
	The Residences at Bella Terra	—			25,000			—			25,000		125,801		25,080		125,721		150,801		11,032		2013	11-Oct
	Los Alisos at Mission Viejo	—			17,298			—			17,298		69,882		16,386		70,794		87,180		4,449		2014	4-Jun
	ORANGE COUNTY, CA	193,873			412,850			377,759			790,609		412,386		443,008		759,987		1,202,995		280,469
	2000 Post Street	—			9,861			44,578			54,439		8,965		10,241		53,163		63,404		24,289		1987	Dec-98
	Birch Creek	—			4,365			16,696			21,061		6,544		5,068		22,537		27,605		12,889		1968	Dec-98
	Highlands Of Marin	—			5,996			24,868			30,864		25,720		7,127		49,457		56,584		26,904		2010	Dec-98
	Marina Playa	—			6,224			23,916			30,140		9,482		6,908		32,714		39,622		18,351		1971	Dec-98
	River Terrace	39,310			22,161			40,137			62,298		3,315		22,359		43,254		65,613		23,857		2005	5-Aug
	CitySouth	—			14,031			30,537			44,568		35,190		16,261		63,497		79,758		30,810		2012	5-Nov
	Bay Terrace	—			8,545			14,458			23,003		4,571		11,424		16,150		27,574		8,710		1962	5-Oct
	Highlands of Marin Phase II	—			5,353			18,559			23,912		11,059		5,753		29,218		34,971		13,438		2010	7-Oct
	Edgewater	—			30,657			83,872			114,529		3,261		30,687		87,103		117,790		34,141		2007	8-Mar
	Almaden Lake Village	27,000			594			42,515			43,109		4,838		741		47,206		47,947		18,420		1999	8-Jul
	388 Beale	—			14,253			74,104			88,357		4,511		14,276		78,592		92,868		16,399		1999	11-Apr
	Channel @ Mission Bay	—			23,625			—			23,625		125,275		23,657		125,243		148,900		7,463		2014	10-Sep
	2000 Post III	—			1,756			7,753			9,509		3,008		3,291		9,226		12,517		5,535		2006	Dec-98
	SAN FRANCISCO, CA	66,310			147,421			421,993			569,414		245,739		157,793		657,360		815,153		241,206
	Rosebeach	—			8,414			17,449			25,863		2,945		8,584		20,224		28,808		11,880		1970	4-Sep
	Tierra Del Rey	32,635			39,586			36,679			76,265		3,008		39,647		39,626		79,273		16,561		1999	7-Dec
	The Westerly	67,700			48,182			102,364			150,546		36,334		50,662		136,218		186,880		35,540		2013	10-Sep
	Jefferson at Marina del Rey	—			55,651			—			55,651		89,717		61,262		84,106		145,368		27,682		2008	7-Sep
	LOS ANGELES, CA	100,335			151,833			156,492			308,325		132,004		160,155		280,174		440,329		91,663
	Crowne Pointe	—			2,486			6,437			8,923		5,074		2,822		11,175		13,997		7,069		1987	Dec-98
	Hilltop	—			2,174			7,408			9,582		3,722		2,668		10,636		13,304		6,431		1985	Dec-98
	The Hawthorne	35,500			6,474			30,226			36,700		3,187		6,575		33,312		39,887		18,512		2003	5-Jul
	The Kennedy	—			6,179			22,307			28,486		1,742		6,242		23,986		30,228		12,640		2005	5-Nov
	Hearthstone at Merrill Creek	22,957			6,848			30,922			37,770		3,180		6,984		33,966		40,950		13,370		2000	8-May
	Island Square	—			21,284			89,389			110,673		4,086		21,413		93,346		114,759		34,577		2007	8-Jul
	Borgata	—			6,379			24,569			30,948		722		6,404		25,287		31,691		11,013		2001	7-May
	elements too	—			27,468			72,036			99,504		14,258		30,100		83,662		113,762		33,927		2010	10-Feb
	989elements	—			8,541			45,990			54,531		1,592		8,552		47,571		56,123		13,663		2006	9-Dec
	Lightbox	—			6,449			38,884			45,333		55		6,449		38,939		45,388		854		2014	14-Aug
	Waterscape	—			9,693			65,176			74,869		50		9,693		65,226		74,919		1,028		2014	14-Sep
	SEATTLE, WA	58,457			103,975			433,344			537,319		37,668		107,902		467,106		575,008		153,084
	Boronda Manor	—			1,946			8,982			10,928		9,398		3,169		17,136		20,305		8,611		1979	Dec-98
	Garden Court	—			888			4,188			5,076		5,304		1,552		8,828		10,380		4,603		1973	Dec-98
					Initial Costs										Gross Amount at Which Carried at Close of Period
		Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
					Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
					Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
	Cambridge Court	—			3,039			12,883			15,922		14,266		5,274		24,914		30,188		13,065		1974	Dec-98
	Laurel Tree	—			1,304			5,115			6,419		5,872		2,139		10,152		12,291		5,264		1977	Dec-98
	The Pointe At Harden Ranch	—			6,388			23,854			30,242		25,703		9,848		46,097		55,945		23,292		1986	Dec-98
	The Pointe At Northridge	—			2,044			8,028			10,072		9,582		3,269		16,385		19,654		8,761		1979	Dec-98
	The Pointe At Westlake	—			1,329			5,334			6,663		6,207		2,154		10,716		12,870		5,276		1975	Dec-98
	MONTEREY PENINSULA, CA	—			16,938			68,384			85,322		76,332		27,405		134,228		161,633		68,872
Verano at Rancho Cucamonga Town Square	46,471			13,557			3,645			17,202		53,385		23,066		47,521		70,587		31,638		2006	2-Oct
Windemere at Sycamore Highland	—			5,810			23,450			29,260		2,656		6,100		25,816		31,916		16,798		2001	2-Nov
Villas at Carlsbad	—			6,517			10,718			17,235		2,181		6,763		12,653		19,416		7,330		1966	4-Oct
Ocean Villas	—			5,135			12,789			17,924		1,817		5,326		14,415		19,741		8,442		1965	4-Oct
OTHER SOUTHERN, CA	46,471			31,019			50,602			81,621		60,039		41,255		100,405		141,660		64,208
Tualatin Heights	—			3,273			9,134			12,407		6,517		3,839		15,085		18,924		9,653		1989	Dec-98
Andover Park	16,818			2,916			16,995			19,911		8,174		3,210		24,875		28,085		16,127		1989	4-Sep
Hunt Club	18,323			6,014			14,870			20,884		5,918		6,364		20,438		26,802		13,604		1985	4-Sep
PORTLAND, OR	35,141			12,203			40,999			53,202		20,609		13,413		60,398		73,811		39,384
TOTAL WEST REGION	500,587			876,239			1,549,573			2,425,812		984,777		950,931		2,459,658		3,410,589		938,886
MID-ATLANTIC REGION
Dominion Middle Ridge	29,820			3,311			13,283			16,594		6,738		3,823		19,509		23,332		13,634		1990	Jun-96
Dominion Lake Ridge	20,372			2,366			8,387			10,753		6,207		2,865		14,095		16,960		9,879		1987	Feb-96
Presidential Greens	—			11,238			18,790			30,028		9,111		11,640		27,499		39,139		18,907		1938	2-May
The Whitmore	—			6,418			13,411			19,829		20,350		7,493		32,686		40,179		21,571		2008	2-Apr
Ridgewood	—			5,612			20,086			25,698		8,108		6,012		27,794		33,806		19,540		1988	2-Aug
DelRay Tower	—			297			12,786			13,083		111,790		9,447		115,426		124,873		2,382		2014	8-Jan
Waterside Towers	—			1,139			49,657			50,796		15,246		36,028		30,014		66,042		19,530		1971	3-Dec
Wellington Place at Olde Town	32,037			13,753			36,059			49,812		17,071		14,650		52,233		66,883		32,364		2008	5-Sep
Andover House	—			14,357			51,577			65,934		3,173		14,373		54,669		69,042		24,673		2004	7-Mar
Sullivan Place	—			1,137			103,676			104,813		5,604		1,373		109,044		110,417		44,942		2007	7-Dec
Circle Towers	70,606			32,815			107,051			139,866		10,812		33,105		117,573		150,678		45,360		1972	8-Mar
Delancey at Shirlington	—			21,606			66,765			88,371		1,770		21,632		68,509		90,141		26,624		2006/2007	8-Mar
View 14	—			5,710			97,941			103,651		2,407		5,721		100,337		106,058		20,042		2009	11-Jun
Signal Hill	—			13,290			—			13,290		69,526		25,399		57,417		82,816		20,799		2010	7-Mar
Capitol View on 14th	—			31,393			—			31,393		94,301		31,394		94,300		125,694		11,374		2013	7-Sep
Domain College Park	31,337			7,300			—			7,300		57,935		7,306		57,929		65,235		4,247		2014	11-Jun
METROPOLITAN, D.C.	184,172			171,742			599,469			771,211		440,149		232,261		979,034		1,211,295		335,868
Dominion Kings Place	14,525			1,565			7,007			8,572		4,199		1,808		10,963		12,771		8,117		1983	Dec-92
Dominion At Eden Brook	—			2,361			9,384			11,745		6,515		2,952		15,308		18,260		11,890		1984	Dec-92
Ellicott Grove	—			2,920			9,099			12,019		23,075		5,306		29,788		35,094		22,140		2008	Jul-94
Dominion Constant Freindship	8,783			903			4,669			5,572		3,941		1,277		8,236		9,513		5,965		1990	May-95
Lakeside Mill	12,569			2,666			10,109			12,775		4,581		2,985		14,371		17,356		10,818		1989	Dec-99
Tamar Meadow	—			4,145			17,150			21,295		5,089		4,577		21,807		26,384		14,882		1990	2-Nov
Calvert’s Walk	—			4,408			24,692			29,100		6,766		4,726		31,140		35,866		19,763		1988	4-Mar
Arborview Apartments	—			4,653			23,952			28,605		7,731		5,209		31,127		36,336		20,296		1992	4-Mar
Liriope Apartments	—			1,620			6,791			8,411		1,250		1,646		8,015		9,661		5,090		1997	4-Mar
20 Lambourne	30,834			11,750			45,590			57,340		5,433		12,018		50,755		62,773		21,218		2003	8-Mar
Domain Brewers Hill	—			4,669			40,630			45,299		581		4,678		41,202		45,880		10,343		2009	10-Aug
BALTIMORE, MD	66,711			41,660			199,073			240,733		69,161		47,182		262,712		309,894		150,522
Dominion English Hills	—			1,979			11,524			13,503		8,224		2,873		18,854		21,727		11,134		1969/1976	Dec-91
Gayton Pointe Townhomes	—			826			5,148			5,974		29,434		3,420		31,988		35,408		25,999		2007	Sep-95
Waterside At Ironbridge	—			1,844			13,239			15,083		7,335		2,299		20,119		22,418		13,123		1987	Sep-97
Carriage Homes at Wyndham	—			474			30,997			31,471		7,560		3,801		35,230		39,031		23,205		1998	3-Nov
				Initial Costs										Gross Amount at Which Carried at Close of Period
	Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
				Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
				Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
Legacy at Mayland	34,567			—			—			—		20,954		1,975		18,979		20,954		18,906		2007	Dec-91
RICHMOND, VA	34,567			5,123			60,908			66,031		73,507		14,368		125,170		139,538		92,367
Eastwind	—			155			5,317			5,472		6,374		659		11,187		11,846		9,145		1970	Apr-88
Dominion Waterside At Lynnhaven	—			1,824			4,107			5,931		6,369		2,337		9,963		12,300		7,634		1966	Aug-96
Heather Lake	—			617			3,400			4,017		10,120		1,205		12,932		14,137		12,126		1972/1974	Mar-80
Dominion Yorkshire Downs	—			1,089			8,582			9,671		6,123		1,594		14,200		15,794		9,290		1987	Dec-97
NORFOLK, VA	—			3,685			21,406			25,091		28,986		5,795		48,282		54,077		38,195
Greens At Schumaker Pond	—			710			6,118			6,828		6,143		1,043		11,928		12,971		8,541		1988	May-95
OTHER MID-ATLANTIC	—			710			6,118			6,828		6,143		1,043		11,928		12,971		8,541
TOTAL MID-ATLANTIC REGION	285,450			222,920			886,974			1,109,894		617,946		300,649		1,427,126		1,727,775		625,493
SOUTHEAST REGION
Summit West	—			2,176			4,710			6,886		8,513		3,236		12,163		15,399		10,443		1972	Dec-92
The Breyley	—			1,780			2,458			4,238		17,167		3,346		18,059		21,405		16,232		2007	Sep-93
Lakewood Place	18,526			1,395			10,647			12,042		8,972		2,329		18,685		21,014		13,790		1986	Mar-94
Bay Meadow	—			2,893			9,254			12,147		10,416		4,277		18,286		22,563		13,550		2004	Dec-96
Cambridge Woods	12,713			1,791			7,166			8,957		8,655		2,613		14,999		17,612		10,681		1985	Jun-97
Sugar Mill Creek	—			2,242			7,553			9,795		6,846		2,734		13,907		16,641		8,998		1988	Dec-98
Inlet Bay	—			7,702			23,150			30,852		14,657		9,211		36,298		45,509		25,585		1988/1989	3-Jun
MacAlpine Place	—			10,869			36,858			47,727		7,384		11,408		43,703		55,111		27,162		2001	4-Dec
The Vintage Lofts at West End	—			6,611			37,663			44,274		15,827		15,120		44,981		60,101		19,020		2009	9-Jul
TAMPA, FL	31,239			37,459			139,459			176,918		98,437		54,274		221,081		275,355		145,461
Seabrook	—			1,846			4,155			6,001		8,052		2,681		11,372		14,053		9,077		2004	Feb-96
The Canopy Apartment Villas	—			2,895			6,456			9,351		21,457		5,470		25,338		30,808		22,904		2008	Mar-93
Altamira Place	—			1,533			11,076			12,609		20,241		3,450		29,400		32,850		24,329		2007	Apr-94
Regatta Shore	—			757			6,608			7,365		15,549		2,018		20,896		22,914		16,423		2007	Jun-94
Alafaya Woods	18,064			1,653			9,042			10,695		8,911		2,522		17,084		19,606		12,624		2006	Oct-94
Los Altos	21,942			2,804			12,349			15,153		10,494		4,020		21,627		25,647		14,273		2004	Oct-96
Lotus Landing	—			2,185			8,639			10,824		9,569		2,841		17,552		20,393		11,184		2006	Jul-97
Seville On The Green	—			1,282			6,498			7,780		6,722		1,705		12,797		14,502		8,546		2004	Oct-97
Ashton @ Waterford	23,388			3,872			17,538			21,410		4,049		4,179		21,280		25,459		12,963		2000	May-98
Arbors at Lee Vista	—			6,692			12,860			19,552		12,591		7,220		24,923		32,143		18,328		2007	6-Aug
ORLANDO, FL	63,394			25,519			95,221			120,740		117,635		36,106		202,269		238,375		150,651
Legacy Hill	—			1,148			5,867			7,015		8,636		1,762		13,889		15,651		10,830		1977	Nov-95
Hickory Run	—			1,469			11,584			13,053		9,761		2,139		20,675		22,814		13,482		1989	Dec-95
Carrington Hills	—			2,117			—			2,117		33,846		4,462		31,501		35,963		20,064		1999	Dec-95
Brookridge	—			708			5,461			6,169		4,500		1,143		9,526		10,669		6,641		1986	Mar-96
Breckenridge	—			766			7,714			8,480		4,357		1,258		11,579		12,837		7,704		1986	Mar-97
Colonnade	16,677			1,460			16,015			17,475		4,934		1,946		20,463		22,409		11,461		1998	Jan-99
The Preserve at Brentwood	22,157			3,182			24,674			27,856		6,276		3,508		30,624		34,132		19,951		1998	4-Jun
Polo Park	—			4,583			16,293			20,876		16,042		5,643		31,275		36,918		20,471		2008	6-May
NASHVILLE, TN	38,834			15,433			87,608			103,041		88,352		21,861		169,532		191,393		110,604
The Reserve and Park at Riverbridge	39,179			15,968			56,401			72,369		8,947		16,536		64,780		81,316		38,317		1999/2001	4-Dec
OTHER FLORIDA	39,179			15,968			56,401			72,369		8,947		16,536		64,780		81,316		38,317
TOTAL SOUTHEAST REGION	172,646			94,379			378,689			473,068		313,371		128,777		657,662		786,439		445,033
NORTHEAST REGION
Garrison Square	—			5,591			91,027			96,618		6,048		5,631		97,035		102,666		23,767		1887/1990	10-Sep
Ridge at Blue Hills	22,839			6,039			34,869			40,908		1,238		6,102		36,044		42,146		9,052		2007	10-Sep
Inwood West	56,447			20,778			88,096			108,874		3,034		19,309		92,599		111,908		20,102		2006	11-Apr
14 North	—			10,961			51,175			62,136		4,563		10,999		55,700		66,699		12,750		2005	11-Apr
BOSTON, MA	79,286			43,369			265,167			308,536		14,883		42,041		281,378		323,419		65,671
				Initial Costs										Gross Amount at Which Carried at Close of Period
	Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
				Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
				Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
10 Hanover Square	190,462			41,432			218,983			260,415		8,396		41,481		227,330		268,811		42,678		2005	11-Apr
21 Chelsea	—			36,399			107,154			143,553		10,915		36,399		118,069		154,468		20,910		2001	11-Aug
View 34	—			114,410			324,920			439,330		85,635		115,024		409,941		524,965		72,318		1985/2013	11-Jul
95 Wall Street	—			57,637			266,255			323,892		6,296		57,736		272,452		330,188		54,973		2008	11-Aug
NEW YORK, NY	190,462			249,878			917,312			1,167,190		111,242		250,640		1,027,792		1,278,432		190,879
TOTAL NORTHEAST REGION	269,748			293,247			1,182,479			1,475,726		126,125		292,681		1,309,170		1,601,851		256,550
SOUTHWEST REGION
THIRTY377	30,023			24,036			32,951			56,987		8,162		24,311		40,838		65,149		21,663		2007	6-Aug
Legacy Village	72,415			16,882			100,102			116,984		7,325		17,280		107,029		124,309		44,321		6/7/05	8-Mar
Garden Oaks	—			2,132			5,367			7,499		1,631		6,936		2,194		9,130		1,842		1979	7-Mar
Glenwood	—			7,903			554			8,457		1,897		8,159		2,195		10,354		1,366		1970	7-May
Talisker of Addison	—			10,440			634			11,074		1,917		10,841		2,150		12,991		1,836		1975	7-May
Springhaven	—			6,688			3,354			10,042		1,289		8,350		2,981		11,331		2,231		1977	7-Apr
Clipper Pointe	—			13,221			2,507			15,728		2,398		14,948		3,178		18,126		2,618		1978	7-May
Highlands of Preston	—			2,151			8,168			10,319		31,139		5,989		35,469		41,458		24,269		2008	Mar-98
DALLAS, TX	102,438			83,453			153,637			237,090		55,758		96,814		196,034		292,848		100,146
Barton Creek Landing	—			3,151			14,269			17,420		22,118		4,807		34,731		39,538		20,260		2010	2-Mar
Residences at the Domain	30,661			4,034			55,256			59,290		2,608		4,200		57,698		61,898		21,988		2007	8-Aug
Red Stone Ranch	—			5,084			17,646			22,730		1,625		5,115		19,240		24,355		3,687		2000	12-Apr
Lakeline Villas	—			4,148			16,869			21,017		1,065		4,159		17,923		22,082		3,370		2004	12-Apr
AUSTIN, TX	30,661			16,417			104,040			120,457		27,416		18,281		129,592		147,873		49,305
TOTAL SOUTHWEST REGION	133,099			99,870			257,677			357,547		83,174		115,095		325,626		440,721		149,451
TOTAL OPERATING COMMUNITIES	1,361,530			1,586,655			4,255,392			5,842,047		2,125,393		1,788,133		6,179,242		7,967,375		2,415,413
REAL ESTATE UNDER DEVELOPMENT
Pier 4	—			24,584			—			24,584		153,048		24,584		153,048		177,632		—
TOTAL REAL ESTATE UNDER DEVELOPMENT	—			24,584			—			24,584		153,048		24,584		153,048		177,632		—
LAND
7 Harcourt	—			884			—			884		4,734		804		4,814		5,618		614
Vitruvian	—			4,325			1,360			5,685		7,965		11,244		2,406		13,650		2,023
Pacific City	—			78,085			—			78,085		7,962		78,085		7,962		86,047		—
Graybar	—			32,938			—			32,938		283		32,938		283		33,221		—
3032 Wilshire	—			9,963			788			10,751		1,642		9,963		2,430		12,393		788
2919 Wilshire	—			6,773			527			7,300		880		6,773		1,407		8,180		527
Waterside	—			11,862			93			11,955		189		12,084		60		12,144		263
TOTAL LAND	—			144,830			2,768			147,598		23,655		151,891		19,362		171,253		4,215
COMMERCIAL
Hanover Village	—			1,624			—			1,624		—		1,104		520		1,624		553
Circle Towers Office Bldg	—			1,407			4,498			5,905		1,516		1,380		6,041		7,421		2,232
Brookhaven Shopping Center	—			4,943			7,093			12,036		9,537		7,793		13,780		21,573		11,676
Bellevue Plaza retail	—			24,377			7,517			31,894		306		29,920		2,280		32,200		636
TOTAL COMMERCIAL	—			32,351			19,108			51,459		11,359		40,197		22,621		62,818		15,097
Other (b)	—			—			—			—		4,181		—		4,181		4,181		47
TOTAL CORPORATE	—			—			—			—		4,181		—		4,181		4,181		47
TOTAL COMMERCIAL & CORPORATE	—			32,351			19,108			51,459		15,540		40,197		26,802		66,999		15,144
TOTAL REAL ESTATE OWNED	$	1,361,530		$	1,788,420		$	4,277,268		$	6,065,688	$	2,317,636	$	2,004,805	$	6,378,454	$	8,383,259	$	2,434,772
(a)	Date of construction or date of last major renovation.
(b)	Includes unallocated accruals and capital expenditures.
The aggregate cost for federal income tax purposes was approximately $7.7 billion at December 31, 2014.
The estimated depreciable lives for all buildings in the latest Consolidated Statements of Operations are 35 to 55 years.
3-YEAR ROLLFORWARD OF REAL ESTATE OWNED AND ACCUMULATED DEPRECIATION
The following is a reconciliation of the carrying amount of total real estate owned at December 31, (in thousands):
	2014			2013			2012
Balance at beginning of the year	$	8,207,977		$	8,055,828		$	8,074,471
Real estate acquired	231,225			—			141,648
Capital expenditures and development	326,461			452,057			422,480
Real estate sold	(269,681		)	(70,687		)	(559,154		)
Real estate contributed to joint ventures	(112,344		)	(356,303		)	—
Consolidation of joint venture assets	—			129,437			—
Retirement of fully depreciated assets	—			—			(13,945		)
Impairment of assets, including casualty-related impairments	(379		)	(2,355		)	(9,672		)
Real estate acquired through JV consolidation	—			—			—
Balance at end of the year	$	8,383,259		$	8,207,977		$	8,055,828
The following is a reconciliation of total accumulated depreciation for real estate owned at December 31, (in thousands):
	2014			2013			2012
Balance at beginning of the year	$	2,208,794		$	1,924,682		$	1,831,727
Depreciation expense for the year	356,673			339,326			340,800
Accumulated depreciation on sales	(126,151		)	(34,794		)	(233,207		)
Accumulated depreciation on real estate contributed to joint ventures	(4,228		)	(20,662		)	—
Accumulated depreciation on assets of consolidated joint ventures	—			1,374			—
Accumulated depreciation on retirements of fully depreciated assets	—			(1,132		)	(13,945		)
Write off of accumulated depreciation on casualty-related impaired assets	(316		)	—			(693		)
Balance at end of year	$	2,434,772		$	2,208,794		$	1,924,682

Schedule_III_Real_Estate_Owned1

Schedule III - Real Estate Owned (UNITED DOMINION REALTY, L.P.)	12 Months Ended
	Dec. 31, 2014
Real Estate and Accumulated Depreciation [Line Items]
Schedule III - Real Estate Owned
					Initial Costs										Gross Amount at Which Carried at Close of Period
		Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
					Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
					Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
	WEST REGION
	Harbor at Mesa Verde	$	50,358		$	20,476		$	28,538		$	49,014	$	12,949	$	21,058	$	40,905	$	61,963	$	26,242	2003	3-Jun
	27 Seventy Five Mesa Verde	30,660			99,329			110,644			209,973		91,693		112,333		189,333		301,666		72,689		1972/2013	4-Oct
	Pacific Shores	34,112			7,345			22,624			29,969		9,150		7,759		31,360		39,119		19,665		2003	3-Jun
	Huntington Vista	27,972			8,055			22,486			30,541		7,637		8,438		29,740		38,178		18,655		1970	3-Jun
	Missions at Back Bay	—			229			14,129			14,358		2,133		10,802		5,689		16,491		3,994		1969	3-Dec
	Coronado at Newport — North	—			62,516			46,082			108,598		24,693		66,756		66,535		133,291		41,982		2000	4-Oct
	Huntington Villas	50,771			61,535			18,017			79,552		7,132		62,223		24,461		86,684		16,061		1972	4-Sep
	Vista Del Rey	—			10,670			7,080			17,750		2,062		10,830		8,982		19,812		5,769		1969	4-Sep
	Foxborough	—			12,071			6,187			18,258		2,749		12,366		8,641		21,007		5,119		1969	4-Sep
	Coronado South	—			58,785			50,067			108,852		17,875		59,277		67,450		126,727		40,783		2000	5-Mar
	1818 Platinum Triangle	—			16,663			51,905			68,568		470		16,693		52,345		69,038		13,682		2009	10-Aug
	Beach & Ocean	—			12,878			—			12,878		38,160		13,007		38,031		51,038		347		2014	11-Aug
	The Residences at Bella Terra	—			25,000			—			25,000		125,801		25,080		125,721		150,801		11,032		2013	11-Oct
	Los Alisos at Mission Viejo	—			17,298			—			17,298		69,882		16,386		70,794		87,180		4,449		2014	4-Jun
	ORANGE COUNTY, CA	193,873			412,850			377,759			790,609		412,386		443,008		759,987		1,202,995		280,469
	2000 Post Street	—			9,861			44,578			54,439		8,965		10,241		53,163		63,404		24,289		1987	Dec-98
	Birch Creek	—			4,365			16,696			21,061		6,544		5,068		22,537		27,605		12,889		1968	Dec-98
	Highlands Of Marin	—			5,996			24,868			30,864		25,720		7,127		49,457		56,584		26,904		2010	Dec-98
	Marina Playa	—			6,224			23,916			30,140		9,482		6,908		32,714		39,622		18,351		1971	Dec-98
	River Terrace	39,310			22,161			40,137			62,298		3,315		22,359		43,254		65,613		23,857		2005	5-Aug
	CitySouth	—			14,031			30,537			44,568		35,190		16,261		63,497		79,758		30,810		2012	5-Nov
	Bay Terrace	—			8,545			14,458			23,003		4,571		11,424		16,150		27,574		8,710		1962	5-Oct
	Highlands of Marin Phase II	—			5,353			18,559			23,912		11,059		5,753		29,218		34,971		13,438		2010	7-Oct
	Edgewater	—			30,657			83,872			114,529		3,261		30,687		87,103		117,790		34,141		2007	8-Mar
	Almaden Lake Village	27,000			594			42,515			43,109		4,838		741		47,206		47,947		18,420		1999	8-Jul
	388 Beale	—			14,253			74,104			88,357		4,511		14,276		78,592		92,868		16,399		1999	11-Apr
	Channel @ Mission Bay	—			23,625			—			23,625		125,275		23,657		125,243		148,900		7,463		2014	10-Sep
	2000 Post III	—			1,756			7,753			9,509		3,008		3,291		9,226		12,517		5,535		2006	Dec-98
	SAN FRANCISCO, CA	66,310			147,421			421,993			569,414		245,739		157,793		657,360		815,153		241,206
	Rosebeach	—			8,414			17,449			25,863		2,945		8,584		20,224		28,808		11,880		1970	4-Sep
	Tierra Del Rey	32,635			39,586			36,679			76,265		3,008		39,647		39,626		79,273		16,561		1999	7-Dec
	The Westerly	67,700			48,182			102,364			150,546		36,334		50,662		136,218		186,880		35,540		2013	10-Sep
	Jefferson at Marina del Rey	—			55,651			—			55,651		89,717		61,262		84,106		145,368		27,682		2008	7-Sep
	LOS ANGELES, CA	100,335			151,833			156,492			308,325		132,004		160,155		280,174		440,329		91,663
	Crowne Pointe	—			2,486			6,437			8,923		5,074		2,822		11,175		13,997		7,069		1987	Dec-98
	Hilltop	—			2,174			7,408			9,582		3,722		2,668		10,636		13,304		6,431		1985	Dec-98
	The Hawthorne	35,500			6,474			30,226			36,700		3,187		6,575		33,312		39,887		18,512		2003	5-Jul
	The Kennedy	—			6,179			22,307			28,486		1,742		6,242		23,986		30,228		12,640		2005	5-Nov
	Hearthstone at Merrill Creek	22,957			6,848			30,922			37,770		3,180		6,984		33,966		40,950		13,370		2000	8-May
	Island Square	—			21,284			89,389			110,673		4,086		21,413		93,346		114,759		34,577		2007	8-Jul
	Borgata	—			6,379			24,569			30,948		722		6,404		25,287		31,691		11,013		2001	7-May
	elements too	—			27,468			72,036			99,504		14,258		30,100		83,662		113,762		33,927		2010	10-Feb
	989elements	—			8,541			45,990			54,531		1,592		8,552		47,571		56,123		13,663		2006	9-Dec
	Lightbox	—			6,449			38,884			45,333		55		6,449		38,939		45,388		854		2014	14-Aug
	Waterscape	—			9,693			65,176			74,869		50		9,693		65,226		74,919		1,028		2014	14-Sep
	SEATTLE, WA	58,457			103,975			433,344			537,319		37,668		107,902		467,106		575,008		153,084
	Boronda Manor	—			1,946			8,982			10,928		9,398		3,169		17,136		20,305		8,611		1979	Dec-98
	Garden Court	—			888			4,188			5,076		5,304		1,552		8,828		10,380		4,603		1973	Dec-98
					Initial Costs										Gross Amount at Which Carried at Close of Period
		Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
					Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
					Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
	Cambridge Court	—			3,039			12,883			15,922		14,266		5,274		24,914		30,188		13,065		1974	Dec-98
	Laurel Tree	—			1,304			5,115			6,419		5,872		2,139		10,152		12,291		5,264		1977	Dec-98
	The Pointe At Harden Ranch	—			6,388			23,854			30,242		25,703		9,848		46,097		55,945		23,292		1986	Dec-98
	The Pointe At Northridge	—			2,044			8,028			10,072		9,582		3,269		16,385		19,654		8,761		1979	Dec-98
	The Pointe At Westlake	—			1,329			5,334			6,663		6,207		2,154		10,716		12,870		5,276		1975	Dec-98
	MONTEREY PENINSULA, CA	—			16,938			68,384			85,322		76,332		27,405		134,228		161,633		68,872
Verano at Rancho Cucamonga Town Square	46,471			13,557			3,645			17,202		53,385		23,066		47,521		70,587		31,638		2006	2-Oct
Windemere at Sycamore Highland	—			5,810			23,450			29,260		2,656		6,100		25,816		31,916		16,798		2001	2-Nov
Villas at Carlsbad	—			6,517			10,718			17,235		2,181		6,763		12,653		19,416		7,330		1966	4-Oct
Ocean Villas	—			5,135			12,789			17,924		1,817		5,326		14,415		19,741		8,442		1965	4-Oct
OTHER SOUTHERN, CA	46,471			31,019			50,602			81,621		60,039		41,255		100,405		141,660		64,208
Tualatin Heights	—			3,273			9,134			12,407		6,517		3,839		15,085		18,924		9,653		1989	Dec-98
Andover Park	16,818			2,916			16,995			19,911		8,174		3,210		24,875		28,085		16,127		1989	4-Sep
Hunt Club	18,323			6,014			14,870			20,884		5,918		6,364		20,438		26,802		13,604		1985	4-Sep
PORTLAND, OR	35,141			12,203			40,999			53,202		20,609		13,413		60,398		73,811		39,384
TOTAL WEST REGION	500,587			876,239			1,549,573			2,425,812		984,777		950,931		2,459,658		3,410,589		938,886
MID-ATLANTIC REGION
Dominion Middle Ridge	29,820			3,311			13,283			16,594		6,738		3,823		19,509		23,332		13,634		1990	Jun-96
Dominion Lake Ridge	20,372			2,366			8,387			10,753		6,207		2,865		14,095		16,960		9,879		1987	Feb-96
Presidential Greens	—			11,238			18,790			30,028		9,111		11,640		27,499		39,139		18,907		1938	2-May
The Whitmore	—			6,418			13,411			19,829		20,350		7,493		32,686		40,179		21,571		2008	2-Apr
Ridgewood	—			5,612			20,086			25,698		8,108		6,012		27,794		33,806		19,540		1988	2-Aug
DelRay Tower	—			297			12,786			13,083		111,790		9,447		115,426		124,873		2,382		2014	8-Jan
Waterside Towers	—			1,139			49,657			50,796		15,246		36,028		30,014		66,042		19,530		1971	3-Dec
Wellington Place at Olde Town	32,037			13,753			36,059			49,812		17,071		14,650		52,233		66,883		32,364		2008	5-Sep
Andover House	—			14,357			51,577			65,934		3,173		14,373		54,669		69,042		24,673		2004	7-Mar
Sullivan Place	—			1,137			103,676			104,813		5,604		1,373		109,044		110,417		44,942		2007	7-Dec
Circle Towers	70,606			32,815			107,051			139,866		10,812		33,105		117,573		150,678		45,360		1972	8-Mar
Delancey at Shirlington	—			21,606			66,765			88,371		1,770		21,632		68,509		90,141		26,624		2006/2007	8-Mar
View 14	—			5,710			97,941			103,651		2,407		5,721		100,337		106,058		20,042		2009	11-Jun
Signal Hill	—			13,290			—			13,290		69,526		25,399		57,417		82,816		20,799		2010	7-Mar
Capitol View on 14th	—			31,393			—			31,393		94,301		31,394		94,300		125,694		11,374		2013	7-Sep
Domain College Park	31,337			7,300			—			7,300		57,935		7,306		57,929		65,235		4,247		2014	11-Jun
METROPOLITAN, D.C.	184,172			171,742			599,469			771,211		440,149		232,261		979,034		1,211,295		335,868
Dominion Kings Place	14,525			1,565			7,007			8,572		4,199		1,808		10,963		12,771		8,117		1983	Dec-92
Dominion At Eden Brook	—			2,361			9,384			11,745		6,515		2,952		15,308		18,260		11,890		1984	Dec-92
Ellicott Grove	—			2,920			9,099			12,019		23,075		5,306		29,788		35,094		22,140		2008	Jul-94
Dominion Constant Freindship	8,783			903			4,669			5,572		3,941		1,277		8,236		9,513		5,965		1990	May-95
Lakeside Mill	12,569			2,666			10,109			12,775		4,581		2,985		14,371		17,356		10,818		1989	Dec-99
Tamar Meadow	—			4,145			17,150			21,295		5,089		4,577		21,807		26,384		14,882		1990	2-Nov
Calvert’s Walk	—			4,408			24,692			29,100		6,766		4,726		31,140		35,866		19,763		1988	4-Mar
Arborview Apartments	—			4,653			23,952			28,605		7,731		5,209		31,127		36,336		20,296		1992	4-Mar
Liriope Apartments	—			1,620			6,791			8,411		1,250		1,646		8,015		9,661		5,090		1997	4-Mar
20 Lambourne	30,834			11,750			45,590			57,340		5,433		12,018		50,755		62,773		21,218		2003	8-Mar
Domain Brewers Hill	—			4,669			40,630			45,299		581		4,678		41,202		45,880		10,343		2009	10-Aug
BALTIMORE, MD	66,711			41,660			199,073			240,733		69,161		47,182		262,712		309,894		150,522
Dominion English Hills	—			1,979			11,524			13,503		8,224		2,873		18,854		21,727		11,134		1969/1976	Dec-91
Gayton Pointe Townhomes	—			826			5,148			5,974		29,434		3,420		31,988		35,408		25,999		2007	Sep-95
Waterside At Ironbridge	—			1,844			13,239			15,083		7,335		2,299		20,119		22,418		13,123		1987	Sep-97
Carriage Homes at Wyndham	—			474			30,997			31,471		7,560		3,801		35,230		39,031		23,205		1998	3-Nov
				Initial Costs										Gross Amount at Which Carried at Close of Period
	Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
				Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
				Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
Legacy at Mayland	34,567			—			—			—		20,954		1,975		18,979		20,954		18,906		2007	Dec-91
RICHMOND, VA	34,567			5,123			60,908			66,031		73,507		14,368		125,170		139,538		92,367
Eastwind	—			155			5,317			5,472		6,374		659		11,187		11,846		9,145		1970	Apr-88
Dominion Waterside At Lynnhaven	—			1,824			4,107			5,931		6,369		2,337		9,963		12,300		7,634		1966	Aug-96
Heather Lake	—			617			3,400			4,017		10,120		1,205		12,932		14,137		12,126		1972/1974	Mar-80
Dominion Yorkshire Downs	—			1,089			8,582			9,671		6,123		1,594		14,200		15,794		9,290		1987	Dec-97
NORFOLK, VA	—			3,685			21,406			25,091		28,986		5,795		48,282		54,077		38,195
Greens At Schumaker Pond	—			710			6,118			6,828		6,143		1,043		11,928		12,971		8,541		1988	May-95
OTHER MID-ATLANTIC	—			710			6,118			6,828		6,143		1,043		11,928		12,971		8,541
TOTAL MID-ATLANTIC REGION	285,450			222,920			886,974			1,109,894		617,946		300,649		1,427,126		1,727,775		625,493
SOUTHEAST REGION
Summit West	—			2,176			4,710			6,886		8,513		3,236		12,163		15,399		10,443		1972	Dec-92
The Breyley	—			1,780			2,458			4,238		17,167		3,346		18,059		21,405		16,232		2007	Sep-93
Lakewood Place	18,526			1,395			10,647			12,042		8,972		2,329		18,685		21,014		13,790		1986	Mar-94
Bay Meadow	—			2,893			9,254			12,147		10,416		4,277		18,286		22,563		13,550		2004	Dec-96
Cambridge Woods	12,713			1,791			7,166			8,957		8,655		2,613		14,999		17,612		10,681		1985	Jun-97
Sugar Mill Creek	—			2,242			7,553			9,795		6,846		2,734		13,907		16,641		8,998		1988	Dec-98
Inlet Bay	—			7,702			23,150			30,852		14,657		9,211		36,298		45,509		25,585		1988/1989	3-Jun
MacAlpine Place	—			10,869			36,858			47,727		7,384		11,408		43,703		55,111		27,162		2001	4-Dec
The Vintage Lofts at West End	—			6,611			37,663			44,274		15,827		15,120		44,981		60,101		19,020		2009	9-Jul
TAMPA, FL	31,239			37,459			139,459			176,918		98,437		54,274		221,081		275,355		145,461
Seabrook	—			1,846			4,155			6,001		8,052		2,681		11,372		14,053		9,077		2004	Feb-96
The Canopy Apartment Villas	—			2,895			6,456			9,351		21,457		5,470		25,338		30,808		22,904		2008	Mar-93
Altamira Place	—			1,533			11,076			12,609		20,241		3,450		29,400		32,850		24,329		2007	Apr-94
Regatta Shore	—			757			6,608			7,365		15,549		2,018		20,896		22,914		16,423		2007	Jun-94
Alafaya Woods	18,064			1,653			9,042			10,695		8,911		2,522		17,084		19,606		12,624		2006	Oct-94
Los Altos	21,942			2,804			12,349			15,153		10,494		4,020		21,627		25,647		14,273		2004	Oct-96
Lotus Landing	—			2,185			8,639			10,824		9,569		2,841		17,552		20,393		11,184		2006	Jul-97
Seville On The Green	—			1,282			6,498			7,780		6,722		1,705		12,797		14,502		8,546		2004	Oct-97
Ashton @ Waterford	23,388			3,872			17,538			21,410		4,049		4,179		21,280		25,459		12,963		2000	May-98
Arbors at Lee Vista	—			6,692			12,860			19,552		12,591		7,220		24,923		32,143		18,328		2007	6-Aug
ORLANDO, FL	63,394			25,519			95,221			120,740		117,635		36,106		202,269		238,375		150,651
Legacy Hill	—			1,148			5,867			7,015		8,636		1,762		13,889		15,651		10,830		1977	Nov-95
Hickory Run	—			1,469			11,584			13,053		9,761		2,139		20,675		22,814		13,482		1989	Dec-95
Carrington Hills	—			2,117			—			2,117		33,846		4,462		31,501		35,963		20,064		1999	Dec-95
Brookridge	—			708			5,461			6,169		4,500		1,143		9,526		10,669		6,641		1986	Mar-96
Breckenridge	—			766			7,714			8,480		4,357		1,258		11,579		12,837		7,704		1986	Mar-97
Colonnade	16,677			1,460			16,015			17,475		4,934		1,946		20,463		22,409		11,461		1998	Jan-99
The Preserve at Brentwood	22,157			3,182			24,674			27,856		6,276		3,508		30,624		34,132		19,951		1998	4-Jun
Polo Park	—			4,583			16,293			20,876		16,042		5,643		31,275		36,918		20,471		2008	6-May
NASHVILLE, TN	38,834			15,433			87,608			103,041		88,352		21,861		169,532		191,393		110,604
The Reserve and Park at Riverbridge	39,179			15,968			56,401			72,369		8,947		16,536		64,780		81,316		38,317		1999/2001	4-Dec
OTHER FLORIDA	39,179			15,968			56,401			72,369		8,947		16,536		64,780		81,316		38,317
TOTAL SOUTHEAST REGION	172,646			94,379			378,689			473,068		313,371		128,777		657,662		786,439		445,033
NORTHEAST REGION
Garrison Square	—			5,591			91,027			96,618		6,048		5,631		97,035		102,666		23,767		1887/1990	10-Sep
Ridge at Blue Hills	22,839			6,039			34,869			40,908		1,238		6,102		36,044		42,146		9,052		2007	10-Sep
Inwood West	56,447			20,778			88,096			108,874		3,034		19,309		92,599		111,908		20,102		2006	11-Apr
14 North	—			10,961			51,175			62,136		4,563		10,999		55,700		66,699		12,750		2005	11-Apr
BOSTON, MA	79,286			43,369			265,167			308,536		14,883		42,041		281,378		323,419		65,671
				Initial Costs										Gross Amount at Which Carried at Close of Period
	Encumbrances			Land and			Buildings			Total Initial		Costs of Improvements Capitalized		Land and		Buildings &		Total		Accumulated		Date of	Date
				Land			and			Acquisition		Subsequent		Land		Buildings		Carrying		Depreciation		Construction(a)	Acquired
				Improvements			Improvements			Costs		to Acquisition Costs		Improvements		Improvements		Value
10 Hanover Square	190,462			41,432			218,983			260,415		8,396		41,481		227,330		268,811		42,678		2005	11-Apr
21 Chelsea	—			36,399			107,154			143,553		10,915		36,399		118,069		154,468		20,910		2001	11-Aug
View 34	—			114,410			324,920			439,330		85,635		115,024		409,941		524,965		72,318		1985/2013	11-Jul
95 Wall Street	—			57,637			266,255			323,892		6,296		57,736		272,452		330,188		54,973		2008	11-Aug
NEW YORK, NY	190,462			249,878			917,312			1,167,190		111,242		250,640		1,027,792		1,278,432		190,879
TOTAL NORTHEAST REGION	269,748			293,247			1,182,479			1,475,726		126,125		292,681		1,309,170		1,601,851		256,550
SOUTHWEST REGION
THIRTY377	30,023			24,036			32,951			56,987		8,162		24,311		40,838		65,149		21,663		2007	6-Aug
Legacy Village	72,415			16,882			100,102			116,984		7,325		17,280		107,029		124,309		44,321		6/7/05	8-Mar
Garden Oaks	—			2,132			5,367			7,499		1,631		6,936		2,194		9,130		1,842		1979	7-Mar
Glenwood	—			7,903			554			8,457		1,897		8,159		2,195		10,354		1,366		1970	7-May
Talisker of Addison	—			10,440			634			11,074		1,917		10,841		2,150		12,991		1,836		1975	7-May
Springhaven	—			6,688			3,354			10,042		1,289		8,350		2,981		11,331		2,231		1977	7-Apr
Clipper Pointe	—			13,221			2,507			15,728		2,398		14,948		3,178		18,126		2,618		1978	7-May
Highlands of Preston	—			2,151			8,168			10,319		31,139		5,989		35,469		41,458		24,269		2008	Mar-98
DALLAS, TX	102,438			83,453			153,637			237,090		55,758		96,814		196,034		292,848		100,146
Barton Creek Landing	—			3,151			14,269			17,420		22,118		4,807		34,731		39,538		20,260		2010	2-Mar
Residences at the Domain	30,661			4,034			55,256			59,290		2,608		4,200		57,698		61,898		21,988		2007	8-Aug
Red Stone Ranch	—			5,084			17,646			22,730		1,625		5,115		19,240		24,355		3,687		2000	12-Apr
Lakeline Villas	—			4,148			16,869			21,017		1,065		4,159		17,923		22,082		3,370		2004	12-Apr
AUSTIN, TX	30,661			16,417			104,040			120,457		27,416		18,281		129,592		147,873		49,305
TOTAL SOUTHWEST REGION	133,099			99,870			257,677			357,547		83,174		115,095		325,626		440,721		149,451
TOTAL OPERATING COMMUNITIES	1,361,530			1,586,655			4,255,392			5,842,047		2,125,393		1,788,133		6,179,242		7,967,375		2,415,413
REAL ESTATE UNDER DEVELOPMENT
Pier 4	—			24,584			—			24,584		153,048		24,584		153,048		177,632		—
TOTAL REAL ESTATE UNDER DEVELOPMENT	—			24,584			—			24,584		153,048		24,584		153,048		177,632		—
LAND
7 Harcourt	—			884			—			884		4,734		804		4,814		5,618		614
Vitruvian	—			4,325			1,360			5,685		7,965		11,244		2,406		13,650		2,023
Pacific City	—			78,085			—			78,085		7,962		78,085		7,962		86,047		—
Graybar	—			32,938			—			32,938		283		32,938		283		33,221		—
3032 Wilshire	—			9,963			788			10,751		1,642		9,963		2,430		12,393		788
2919 Wilshire	—			6,773			527			7,300		880		6,773		1,407		8,180		527
Waterside	—			11,862			93			11,955		189		12,084		60		12,144		263
TOTAL LAND	—			144,830			2,768			147,598		23,655		151,891		19,362		171,253		4,215
COMMERCIAL
Hanover Village	—			1,624			—			1,624		—		1,104		520		1,624		553
Circle Towers Office Bldg	—			1,407			4,498			5,905		1,516		1,380		6,041		7,421		2,232
Brookhaven Shopping Center	—			4,943			7,093			12,036		9,537		7,793		13,780		21,573		11,676
Bellevue Plaza retail	—			24,377			7,517			31,894		306		29,920		2,280		32,200		636
TOTAL COMMERCIAL	—			32,351			19,108			51,459		11,359		40,197		22,621		62,818		15,097
Other (b)	—			—			—			—		4,181		—		4,181		4,181		47
TOTAL CORPORATE	—			—			—			—		4,181		—		4,181		4,181		47
TOTAL COMMERCIAL & CORPORATE	—			32,351			19,108			51,459		15,540		40,197		26,802		66,999		15,144
TOTAL REAL ESTATE OWNED	$	1,361,530		$	1,788,420		$	4,277,268		$	6,065,688	$	2,317,636	$	2,004,805	$	6,378,454	$	8,383,259	$	2,434,772
(a)	Date of construction or date of last major renovation.
(b)	Includes unallocated accruals and capital expenditures.
The aggregate cost for federal income tax purposes was approximately $7.7 billion at December 31, 2014.
The estimated depreciable lives for all buildings in the latest Consolidated Statements of Operations are 35 to 55 years.
3-YEAR ROLLFORWARD OF REAL ESTATE OWNED AND ACCUMULATED DEPRECIATION
The following is a reconciliation of the carrying amount of total real estate owned at December 31, (in thousands):
	2014			2013			2012
Balance at beginning of the year	$	8,207,977		$	8,055,828		$	8,074,471
Real estate acquired	231,225			—			141,648
Capital expenditures and development	326,461			452,057			422,480
Real estate sold	(269,681		)	(70,687		)	(559,154		)
Real estate contributed to joint ventures	(112,344		)	(356,303		)	—
Consolidation of joint venture assets	—			129,437			—
Retirement of fully depreciated assets	—			—			(13,945		)
Impairment of assets, including casualty-related impairments	(379		)	(2,355		)	(9,672		)
Real estate acquired through JV consolidation	—			—			—
Balance at end of the year	$	8,383,259		$	8,207,977		$	8,055,828
The following is a reconciliation of total accumulated depreciation for real estate owned at December 31, (in thousands):
	2014			2013			2012
Balance at beginning of the year	$	2,208,794		$	1,924,682		$	1,831,727
Depreciation expense for the year	356,673			339,326			340,800
Accumulated depreciation on sales	(126,151		)	(34,794		)	(233,207		)
Accumulated depreciation on real estate contributed to joint ventures	(4,228		)	(20,662		)	—
Accumulated depreciation on assets of consolidated joint ventures	—			1,374			—
Accumulated depreciation on retirements of fully depreciated assets	—			(1,132		)	(13,945		)
Write off of accumulated depreciation on casualty-related impaired assets	(316		)	—			(693		)
Balance at end of year	$	2,434,772		$	2,208,794		$	1,924,682
United Dominion Reality L.P.
Real Estate and Accumulated Depreciation [Line Items]
Schedule III - Real Estate Owned
					Initial Costs										Gross Amount at Which Carried at Close of Period
		Encumbrances			Land and Land Improvements			Building and Improvements			Total Initial Acquisition Costs		Cost of Improvements Capitalized Subsequent to Acquisition Costs		Land and Land Improvements		Buildings & Buildings Improvements		Total Carrying Value		Accumulated Depreciation		Date of Construction (a)	Date Acquired
	WEST REGION
	Harbor at Mesa Verde	$	50,358		$	20,476		$	28,538		$	49,014	$	12,949	$	21,058	$	40,905	$	61,963	$	26,242	2003	3-Jun
	27 Seventy Five Mesa Verde	30,660			99,329			110,644			209,973		91,693		112,333		189,333		301,666		72,689		1972/2013	4-Oct
	Pacific Shores	34,112			7,345			22,624			29,969		9,150		7,759		31,360		39,119		19,665		2003	3-Jun
	Huntington Vista	27,972			8,055			22,486			30,541		7,637		8,438		29,740		38,178		18,655		1970	3-Jun
	Missions at Back Bay	—			229			14,129			14,358		2,133		10,802		5,689		16,491		3,994		1969	3-Dec
	Coronado at Newport — North	—			62,516			46,082			108,598		24,693		66,756		66,535		133,291		41,982		2000	4-Oct
	Huntington Villas	50,771			61,535			18,017			79,552		7,132		62,223		24,461		86,684		16,061		1972	4-Sep
	Vista Del Rey	—			10,670			7,080			17,750		2,062		10,830		8,982		19,812		5,769		1969	4-Sep
	Coronado South	—			58,785			50,067			108,852		17,875		59,277		67,450		126,727		40,783		2000	5-Mar
	ORANGE COUNTY, CA	193,873			328,940			319,667			648,607		175,324		359,476		464,455		823,931		245,840
	2000 Post Street	—			9,861			44,578			54,439		8,965		10,241		53,163		63,404		24,289		1987	Dec-98
	Birch Creek	—			4,365			16,696			21,061		6,544		5,068		22,537		27,605		12,889		1968	Dec-98
	Highlands Of Marin	—			5,996			24,868			30,864		25,720		7,127		49,457		56,584		26,904		2010	Dec-98
	Marina Playa	—			6,224			23,916			30,140		9,482		6,908		32,714		39,622		18,351		1971	Dec-98
	River Terrace	39,310			22,161			40,137			62,298		3,315		22,359		43,254		65,613		23,857		2005	5-Aug
	CitySouth	—			14,031			30,537			44,568		35,190		16,261		63,497		79,758		30,810		2012	5-Nov
	Bay Terrace	—			8,545			14,458			23,003		4,571		11,424		16,150		27,574		8,710		1962	5-Oct
	Highlands of Marin Phase II	—			5,353			18,559			23,912		11,059		5,753		29,218		34,971		13,438		2010	7-Oct
	Edgewater	—			30,657			83,872			114,529		3,261		30,687		87,103		117,790		34,141		2007	8-Mar
	Almaden Lake Village	27,000			594			42,515			43,109		4,838		741		47,206		47,947		18,420		1999	8-Jul
	SAN FRANCISCO, CA	66,310			107,787			340,136			447,923		112,945		116,569		444,299		560,868		211,809
	Rosebeach	—			8,414			17,449			25,863		2,945		8,584		20,224		28,808		11,880		1970	4-Sep
	Tierra Del Rey	32,635			39,586			36,679			76,265		3,008		39,647		39,626		79,273		16,561		1999	7-Dec
	LOS ANGELES, CA	32,635			48,000			54,128			102,128		5,953		48,231		59,850		108,081		28,441
	Crowne Pointe	—			2,486			6,437			8,923		5,074		2,822		11,175		13,997		7,069		1987	Dec-98
	Hilltop	—			2,174			7,408			9,582		3,722		2,668		10,636		13,304		6,431		1985	Dec-98
	The Kennedy	—			6,179			22,307			28,486		1,742		6,242		23,986		30,228		12,640		2005	5-Nov
	Hearthstone at Merrill Creek	22,957			6,848			30,922			37,770		3,180		6,984		33,966		40,950		13,370		2000	8-May
	Island Square	—			21,284			89,389			110,673		4,086		21,413		93,346		114,759		34,577		2007	8-Jul
	SEATTLE, WA	22,957			38,971			156,463			195,434		17,804		40,129		173,109		213,238		74,087
	Boronda Manor	—			1,946			8,982			10,928		9,377		3,169		17,136		20,305		8,611		1979	Dec-98
	Garden Court	—			888			4,188			5,076		5,304		1,552		8,828		10,380		4,603		1973	Dec-98
	Cambridge Court	—			3,039			12,883			15,922		14,266		5,274		24,914		30,188		13,065		1974	Dec-98
	Laurel Tree	—			1,304			5,115			6,419		5,872		2,139		10,152		12,291		5,264		1977	Dec-98
	The Pointe At Harden Ranch	—			6,388			23,854			30,242		25,703		9,848		46,097		55,945		23,292		1986	Dec-98
	The Pointe At Northridge	—			2,044			8,028			10,072		9,582		3,269		16,385		19,654		8,761		1979	Dec-98
	The Pointe At Westlake	—			1,329			5,334			6,663		6,207		2,154		10,716		12,870		5,276		1975	Dec-98
	MONTEREY PENINSULA, CA	—			16,938			68,384			85,322		76,311		27,405		134,228		161,633		68,872
	Verano at Rancho Cucamonga Town Square	46,471			13,557			3,645			17,202		53,385		23,066		47,521		70,587		31,638		2006	2-Oct
	Villas at Carlsbad	—			6,517			10,718			17,235		2,181		6,763		12,653		19,416		7,330		1966	4-Oct
	Ocean Villas	—			5,135			12,789			17,924		1,817		5,326		14,415		19,741		8,442		1965	4-Oct
	OTHER SOUTHERN, CA	46,471			25,209			27,152			52,361		57,383		35,155		74,589		109,744		47,410
	Tualatin Heights	—			3,273			9,134			12,407		6,517		3,839		15,085		18,924		9,653		1989	Dec-98
	Andover Park	16,818			2,916			16,995			19,911		8,174		3,210		24,875		28,085		16,127		1989	4-Sep
	Hunt Club	18,323			6,014			14,870			20,884		5,918		6,364		20,438		26,802		13,604		1985	4-Sep
	PORTLAND, OR	35,141			12,203			40,999			53,202		20,609		13,413		60,398		73,811		39,384
	TOTAL WEST REGION	397,387			578,048			1,006,929			1,584,977		466,329		640,378		1,410,928		2,051,306		715,843
					Initial Costs										Gross Amount at Which Carried at Close of Period
		Encumbrances			Land and Land Improvements			Building and Improvements			Total Initial Acquisition Costs		Cost of Improvements Capitalized Subsequent to Acquisition Costs		Land and Land Improvements		Buildings & Buildings Improvements		Total Carrying Value		Accumulated Depreciation		Date of Construction (a)	Date Acquired
	MID-ATLANTIC REGION
	The Whitmore	—			6,418			13,411			19,829		20,350		7,493		32,686		40,179		21,571		2008	2-Apr
	Ridgewood	—			5,612			20,086			25,698		8,108		6,012		27,794		33,806		19,540		1988	2-Aug
	DelRey Tower	—			297			12,786			13,083		111,790		9,447		115,426		124,873		2,382		2014	8-Jan
	Wellington Place at Olde Town	32,037			13,753			36,059			49,812		17,071		14,650		52,233		66,883		32,364		2008	5-Sep
	Andover House	—			14,357			51,577			65,934		3,108		14,373		54,669		69,042		24,673		2004	7-Mar
	Sullivan Place	—			1,137			103,676			104,813		5,604		1,373		109,044		110,417		44,942		2007	7-Dec
	Circle Towers	70,606			32,815			107,051			139,866		10,812		33,105		117,573		150,678		45,360		1972	8-Mar
	Delancey at Shirlington	—			21,606			66,765			88,371		1,770		21,632		68,509		90,141		26,624		2006/2007	8-Mar
	METROPOLITAN D.C.	102,643			95,995			411,411			507,406		178,613		108,085		577,934		686,019		217,456
	Lakeside Mill	12,569			2,666			10,109			12,775		4,581		2,985		14,371		17,356		10,818		1989	Dec-99
Tamar Meadow	—			4,145			17,150			21,295		5,089		4,577		21,807		26,384		14,882		1990	2-Nov
Calvert’s Walk	—			4,408			24,692			29,100		6,766		4,726		31,140		35,866		19,763		1988	4-Mar
Liriope Apartments	—			1,620			6,791			8,411		1,250		1,646		8,015		9,661		5,090		1997	4-Mar
20 Lambourne	30,834			11,750			45,590			57,340		5,433		12,018		50,755		62,773		21,218		2003	8-Mar
BALTIMORE, MD	43,403			24,589			104,332			128,921		23,119		25,952		126,088		152,040		71,771
TOTAL MID-ATLANTIC REGION	146,046			120,584			515,743			636,327		201,732		134,037		704,022		838,059		289,227
SOUTHEAST REGION
Sugar Mill Creek	—			2,242			7,553			9,795		6,846		2,734		13,907		16,641		8,998		1988	Dec-98
Inlet Bay	—			7,702			23,150			30,852		14,657		9,211		36,298		45,509		25,585		1988/1989	3-Jun
MacAlpine Place	—			10,869			36,858			47,727		7,384		11,408		43,703		55,111		27,162		2001	4-Dec
TAMPA, FL	—			20,813			67,561			88,374		28,887		23,353		93,908		117,261		61,745
Legacy Hill	—			1,148			5,867			7,015		8,636		1,762		13,889		15,651		10,830		1977	Nov-95
Hickory Run	—			1,469			11,584			13,053		9,761		2,139		20,675		22,814		13,482		1989	Dec-95
Carrington Hills	—			2,117			—			2,117		33,846		4,462		31,501		35,963		20,064		1999	Dec-95
Brookridge	—			708			5,461			6,169		4,500		1,143		9,526		10,669		6,641		1986	Mar-96
Breckenridge	—			766			7,714			8,480		4,357		1,258		11,579		12,837		7,704		1986	Mar-97
Polo Park	—			4,583			16,293			20,876		16,042		5,643		31,275		36,918		20,471		2008	6-May
NASHVILLE, TN	—			10,791			46,919			57,710		77,142		16,407		118,445		134,852		79,192
The Reserve and Park at Riverbridge	39,179			15,968			56,401			72,369		8,947		16,536		64,780		81,316		38,317		1999/2001	4-Dec
OTHER FLORIDA	39,179			15,968			56,401			72,369		8,947		16,536		64,780		81,316		38,317
TOTAL SOUTHEAST REGION	39,179			47,572			170,881			218,453		114,976		56,296		277,133		333,429		179,254
NORTHEAST REGION
Inwood West	56,447			20,778			88,096			108,874		3,034		19,309		92,599		111,908		20,102		2006	11-Apr
14 North	—			10,961			51,175			62,136		4,563		10,999		55,700		66,699		12,750		2005	11-Apr
BOSTON, MA	56,447			31,739			139,271			171,010		7,597		30,308		148,299		178,607		32,852
10 Hanover Square	190,462			41,432			218,983			260,415		8,396		41,481		227,330		268,811		42,678		2005	11-Apr
95 Wall Street	—			57,637			266,255			323,892		6,296		57,736		272,452		330,188		54,973		2008	11-Aug
NEW YORK, NY	190,462			99,069			485,238			584,307		14,692		99,217		499,782		598,999		97,651
TOTAL NORTHEAST REGION	246,909			130,808			624,509			755,317		22,289		129,525		648,081		777,606		130,503
SOUTHWEST REGION
THIRTY377	30,023			24,036			32,951			56,987		8,162		24,311		40,838		65,149		21,663		2007	6-Aug
Legacy Village	72,415			16,882			100,102			116,984		7,325		17,280		107,029		124,309		44,321		6/7/05	8-Mar
DALLAS, TX	102,438			40,918			133,053			173,971		15,487		41,591		147,867		189,458		65,984
Barton Creek Landing	—			3,151			14,269			17,420		22,118		4,807		34,731		39,538		20,260		2010	2-Mar
AUSTIN, TX	—			3,151			14,269			17,420		22,118		4,807		34,731		39,538		20,260
TOTAL SOUTHWEST REGION	102,438			44,069			147,322			191,391		37,605		46,398		182,598		228,996		86,244
TOTAL OPERATING COMMUNITIES	931,959			921,081			2,465,384			3,386,465		842,931		1,006,634		3,222,762		4,229,396		1,401,071
COMMERCIAL
Circle Towers Office Bldg	—			1,407			4,498			5,905		1,516		1,380		6,041		7,421		2,232
TOTAL COMMERCIAL	—			1,407			4,498			5,905		1,516		1,380		6,041		7,421		2,232
Other (b)	—			—			—			—		1,953		—		1,953		1,953		—
TOTAL CORPORATE	—			—			—			—		1,953		—		1,953		1,953		—
TOTAL COMMERCIAL & CORPORATE	—			1,407			4,498			5,905		3,469		1,380		7,994		9,374		2,232
TOTAL REAL ESTATE OWNED	$	931,959		$	922,488		$	2,469,882		$	3,392,370	$	846,400	$	1,008,014	$	3,230,756	$	4,238,770	$	1,403,303
(a)	Date of construction or date of last major renovation.
(b)	Includes unallocated accruals and capital expenditures.
The aggregate cost for federal income tax purpose was approximately $3.6 billion at December 31, 2011.
The estimated depreciable lives for all buildings in the latest Consolidated Statements of Operations are 35 to 55 years.
3-YEAR ROLLFORWARD OF REAL ESTATE OWNED AND ACCUMULATED DEPRECIATION
The following is a reconciliation of the carrying amount of total real estate owned at December 31, (in thousands):
	2014			2013			2012
Balance at beginning of the year	$	4,188,480		$	4,182,920		$	4,205,298
Capital expenditures and development	91,682			151,002			115,355
Real estate sold	(41,013		)	(70,687		)	(116,166		)
Real estate transferred to the General Partner	—			(74,755		)	—
Retirement of fully depreciated asset	—			—			(13,945		)
Casualty-related impairment of assets	(379		)	—			(7,622		)
Balance at end of year	$	4,238,770		$	4,188,480		$	4,182,920
The following is a reconciliation of total accumulated depreciation for real estate owned at December 31, (in thousands):
	2014			2013			2012
Balance at beginning of the year	$	1,241,574		$	1,097,133		$	976,358
Depreciation expense for the year	178,719			179,404			189,362
Accumulated depreciation on sales	(16,674		)	(34,794		)	(54,085		)
Accumulated depreciation on retirements of fully depreciated asset	—			—			(13,945		)
Accumulated depreciation on property transferred to the General Partner	—			(169		)	—
Write off of accumulated depreciation on casualty-related impaired assets	(316		)	—			(557		)
Balance at end of year	$	1,403,303		$	1,241,574		$	1,097,133

IncomeLoss_Per_Share_UNITED_DO

Income/(Loss) Per Share (UNITED DOMINION REALTY, L.P.) (Notes)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Text Block]	INCOME/(LOSS) PER SHARE
	The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data):
		Year Ended December 31,
		2014				2013			2012
	Numerator for income/(loss) per share:
	Income/(loss) from continuing operations	$	16,260			$	2,340		$	(46,305	)
	Gain/(loss) on sale of real estate owned, net of tax	143,572				—			—
	(Income)/loss from continuing operations attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)		48			2,089
	(Income)/loss from continuing operations attributable to noncontrolling interests	3				60			(140		)
	Income/(loss) from continuing operations attributable to UDR, Inc.	154,324				2,448			(44,356		)
	Distributions to preferred stockholders - Series E (Convertible)	(3,724		)		(3,724		)	(3,724		)
	Distributions to preferred stockholders - Series G	—				—			(2,286		)
	Premium on preferred stock redemption or repurchases, net	—				—			(2,791		)
	Income/(loss) from continuing operations attributable to common stockholders	$	150,600			$	(1,276	)	$	(53,157	)
	Income/(loss) from discontinued operations, net of tax	$	10			$	43,942		$	266,608
	(Income)/loss from discontinued operations attributable to redeemable noncontrolling interests in the Operating Partnership	—				(1,578		)	(10,075		)
	Income/(loss) from discontinued operations attributable to common stockholders	$	10			$	42,364		$	256,533
	Net income/(loss) attributable to common stockholders	$	150,610			$	41,088		$	203,376
	Denominator for income/(loss) per share - basic and diluted:
	Weighted average common shares outstanding	252,707				250,684			239,482
	Non-vested restricted stock awards	(1,179		)		(715		)	(631		)
	Denominator for income/(loss) per share - basic	251,528				249,969			238,851
	Incremental shares issuable from assumed conversion of:	1,917				—			—
	Stock options and unvested resticted stock
	Denominator for income/(loss) per share - diluted	253,445				249,969			238,851
	Income/(loss) per weighted average common share - basic:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.6			$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.6			$	0.16		$	0.85
	Income/(loss) per weighted average common share - diluted:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.59			$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.59			$	0.16		$	0.85
	Basic income/(loss) per common share is computed based upon the weighted average number of common shares outstanding. Diluted income/(loss) per share is computed based upon the common shares issuable from the assumed conversion of the OP Units, convertible preferred stock, stock options, and restricted stock. Only those instruments having a dilutive impact on our basic income/(loss) per share are included in diluted income/(loss) per share during the periods.
	During the years ended December 31, 2013 and 2012, the effect of the conversion of the OP Units, convertible preferred stock, stock options and restricted stock is not dilutive, and is therefore not included in the above calculations as the Company reported a loss from continuing operations attributable to common stockholders.
	The following table sets forth the additional shares of common stock outstanding by equity instrument if converted to common stock for each of the years ended December 31, 2014, 2013, and 2012 (shares in thousands):
		Year Ended December 31,
		2014			2013			2012
	OP Units	9,247			9,337			9,411
	Preferred Stock	3,036			3,036			3,036
	Stock options and unvested restricted stock	1,917			1,584			1,361
United Dominion Reality L P [Member]
Earnings Per Share [Text Block]	INCOME/(LOSS) PER OPERATING PARTNERSHIP UNIT
	Basic income/(loss) per OP Unit is computed by dividing net income/(loss) attributable to general and limited partner unitholders by the weighted average number of general and limited partner units (including redeemable OP Units) outstanding during the year. Diluted income/(loss) per OP Unit reflects the potential dilution that could occur if securities or other contracts to issue OP Units were exercised or converted into OP Units or resulted in the issuance of OP Units and then shared in the income/(loss) of the Operating Partnership. For the years ended December 31, 2014, 2013, and 2012, there were no dilutive instruments, and therefore, diluted income/(loss) per OP Unit and basic income/(loss) per OP Unit are the same. See Note 9, Capital Structure, for further discussion on redemption rights of OP Units.
	The following table sets forth the computation of basic and diluted income/(loss) per OP Unit for the periods presented (dollars in thousands, except per OP Unit data):
		Year Ended December 31,
		2014				2013			2012
	Numerator for income/(loss) per OP Unit — basic and diluted:
	Income/(loss) from continuing operations	$	33,544			$	32,766		$	(13,309	)
	Gain/(loss) on sale of real estate owned	63,635				—			—
	(Income)/loss from continuing operations attributable to noncontrolling interests	(952		)		(4,114		)	(100		)
	Income/(loss) from continuing operations attributable to OP unitholders	$	96,227			$	28,652		$	(13,409	)
	Income/(loss) from discontinued operations	$	—			$	45,176		$	57,643
	(Income)/loss from discontinued operations attributable to noncontrolling interests	—				(452		)	(252		)
	Income/(loss) from discontinued operations attributable to OP unitholders	$	—			$	44,724		$	57,391
	Net income/(loss)	$	97,179			$	77,942		$	44,334
	Net (income)/loss attributable to noncontrolling interests	(952		)		(4,566		)	(352		)
	Net income/(loss) attributable to OP unitholders	$	96,227			$	73,376		$	43,982
	Denominator for income/(loss) per OP Unit — basic and diluted:
	Weighted average OP Units outstanding — basic and diluted	183,279				184,196			184,281
	Income/(loss) per weighted average OP Unit — basic and diluted:
	Income/(loss) from continuing operations attributable to OP unitholders	$	0.53			$	0.16		$	(0.07	)
	Income/(loss) from discontinued operations attributable to OP unitholders	—				0.24			0.31
	Net income/(loss) attributable to OP unitholders	$	0.53			$	0.4		$	0.24

Significant_Accounting_Policie2

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In April 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, which incorporates a requirement that a disposition represent a strategic shift in an entity’s operations into the definition of a discontinued operation. In accordance with the ASU, a discontinued operation represents (1) a component of an entity or group of components that has been disposed of or is classified as held for sale in a single transaction and represents a strategic shift that has or will have a major effect on an entity’s financial results, or (2) an acquired business that is classified as held for sale on the date of acquisition. A strategic shift could include a disposal of (1) a separate major line of business, (2) a separate major geographic area of operations, (3) a major equity method investment, or (4) other major parts of an entity. The standard requires prospective application and will be effective for interim and annual periods beginning on or after December 15, 2014, with early adoption permitted. The early adoption provision excludes components of an entity that were sold or classified as held for sale prior to the adoption of the standard.
	The Company elected to early adopt this standard effective January 1, 2014, which had a significant impact on the Company’s consolidated financial statements as further discussed in Note 3, Discontinued Operations. Subsequent to the Company’s adoption of ASU 2014-08, the sale of real estate that does not meet the definition of a discontinued operation under the standard is included in Gain/(loss) on sale of real estate owned, net of tax on the Consolidated Statements of Operations.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The updated standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The standard specifically excludes lease contracts. The ASU allows for the use of either the full or modified retrospective transition method, and the standard will be effective for the Company on January 1, 2017; early adoption is not permitted. The Company has not yet selected a transition method and we are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures.
Real estate	Real Estate
	Real estate assets held for investment are carried at historical cost and consist of land, buildings and improvements, furniture, fixtures and equipment and other costs incurred during their development, acquisition and redevelopment.
	Expenditures for ordinary repair and maintenance costs are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to the acquisition and/or improvement of real estate assets are capitalized and depreciated over their estimated useful lives if the expenditures qualify as a betterment or the life of the related asset will be substantially extended beyond the original life expectancy.
	UDR purchases real estate investment properties and records the tangible and identifiable intangible assets and liabilities acquired based on their estimated fair value. The primary, although not only, identifiable intangible asset associated with our portfolio is the value of existing lease agreements. When recording the acquisition of a community, we first assign fair value to the estimated intangible value of the existing lease agreements and then to the estimated value of the land, building and fixtures assuming the community is vacant. The Company estimates the intangible value of the lease agreements by determining the lost revenue associated with a hypothetical lease-up. Depreciation on the building is based on the expected useful life of the asset and the in-place leases are amortized over their remaining average contractual life. Property acquisition costs are expensed as incurred.
	Quarterly or when changes in circumstances warrant, UDR will assess our real estate properties for indicators of impairment. In determining whether the Company has indicators of impairment in our real estate assets, we assess whether the long-lived asset’s carrying value exceeds the community’s undiscounted future cash flows, which is representative of projected net operating income (“NOI”) plus the residual value of the community. Our future cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. If such indicators of impairment are present and the carrying value exceeds the undiscounted cash flows of the community, an impairment loss is recognized equal to the excess of the carrying amount of the asset over its estimated fair value. Our estimates of fair market value represent our best estimate based primarily upon unobservable inputs related to rental rates, operating costs, growth rates, discount rates, capitalization rates, industry trends and reference to market rates and transactions.
	For long-lived assets to be disposed of, impairment losses are recognized when the fair value of the asset less estimated cost to sell is less than the carrying value of the asset. Properties classified as real estate held for sale generally represent properties that are actively marketed or contracted for sale with the closing expected to occur within the next twelve months. Real estate held for sale is carried at the lower of cost, net of accumulated depreciation, or fair value, less the cost to sell, determined on an asset-by-asset basis. Expenditures for ordinary repair and maintenance costs on held for sale properties are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to held for sale properties are capitalized at cost. Depreciation is not recorded on real estate held for sale.
	Depreciation is computed on a straight-line basis over the estimated useful lives of the related assets which are 35 to 55 years for buildings, 10 to 35 years for major improvements, and 3 to 10 years for furniture, fixtures, equipment, and other assets.
	Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation. The Company capitalizes costs directly related to the predevelopment, development, and redevelopment of a capital project, which include, but are not limited to, interest, real estate taxes, insurance, and allocated development and redevelopment overhead related to support costs for personnel working on the capital projects. We use our professional judgment in determining whether such costs meet the criteria for capitalization or must be expensed as incurred. These costs are capitalized only during the period in which activities necessary to ready an asset for its intended use are in progress and such costs are incremental and identifiable to a specific activity to get the asset ready for its intended use. These costs, excluding the direct costs of development and redevelopment and capitalized interest, for the years ended December 31, 2014, 2013, and 2012 were $9.0 million, $11.1 million and $10.0 million, respectively. During the years ended December 31, 2014, 2013, and 2012, total interest capitalized was $20.2 million, $29.4 million, and $26.4 million, respectively. As each home in a capital project is completed and becomes available for lease-up, the Company ceases capitalization on the related portion and depreciation commences over the estimated useful life.
Cash and cash equivalents	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash on hand, demand deposits with financial institutions and short-term, highly liquid investments. We consider all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The majority of the Company’s cash and cash equivalents are held at major commercial banks.
Restricted cash	Restricted Cash
	Restricted cash consists of escrow deposits held by lenders for real estate taxes, insurance and replacement reserves, and security deposits.
Revenue and real estate sales gain recognition	Revenue and Real Estate Sales Gain Recognition
	Rental income related to leases is recognized on an accrual basis when due from residents and tenants in accordance with GAAP. Rental payments are generally due on a monthly basis and recognized when earned. The Company recognizes interest income, management and other fees and incentives when earned, and the amounts are fixed and determinable.
	For sale transactions meeting the requirements for full accrual profit recognition, we remove the related assets and liabilities from our Consolidated Balance Sheets and record the gain or loss in the period the transaction closes. For sale transactions that do not meet the full accrual sale criteria due to our continuing involvement, we evaluate the nature of the continuing involvement and account for the transaction under an alternate method of accounting. Unless certain limited criteria are met, non-monetary transactions, including property exchanges, are accounted for at fair value.
	Sales to entities in which we retain or otherwise own an interest are accounted for as partial sales. If all other requirements for recognizing profit under the full accrual method have been satisfied and no other forms of continuing involvement are present, we recognize profit proportionate to the outside interest in the buyer and defer the gain on the interest we retain. The Company recognizes any deferred gain when the property is sold to a third party. In transactions accounted for by us as partial sales, we determine if the buyer of the majority equity interest in the venture was provided a preference as to cash flows in either an operating or a capital waterfall. If a cash flow preference has been provided, we recognize profit only to the extent that proceeds from the sale of the majority equity interest exceed costs related to the entire property.
Notes Receivable	Notes Receivable
	The following table summarizes our notes receivable, net as of December 31, 2014 and 2013 (dollars in thousands):
		Interest rate at December 31, 2014		Balance Outstanding
				December 31, 2014		December 31, 2013
	Note due June 2014 (a)			$	—	$	40,800
	Note due February 2017 (b)	10	%	11,869		14,580
	Note due July 2017 (c)	8	%	2,500		1,400
	Note due June 2022 (net of discount of $0 and $247, respectively) (d)			—		26,253
	Total notes receivable, net			$	14,369	$	83,033
	(a) In the fourth quarter of 2013, in conjunction with the sale of its 95% interest in the Lodge at Stoughton, one of its unconsolidated joint ventures, the Company provided the buyer with a $40.8 million loan secured by the property at LIBOR plus a spread of 350 basis points with two three-month extension options at increased rates and a financing fee. In June 2014, the note was paid in full.
	(b) The Company has a secured note receivable with an unaffiliated third party with an aggregate commitment of $11.9 million, which bears an interest rate of 10.00% per annum. During the year ended December 31, 2014, the Company loaned an additional $1.2 million and received a payment of $3.9 million in the fourth quarter under this note. Interest payments are due monthly. The note matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) the fifth anniversary of the date of the note (February 2017).
	(c) The Company has a secured note receivable with an unaffiliated third party with an aggregate commitment of $2.5 million, which bears an interest rate of 8.00% per annum. During the year ended December 31, 2014, the Company loaned an additional $1.1 million under the note. Interest payments are due monthly. The note matures at the earliest of the following: (a) the closing of any private or public capital raising in the amount of $5.0 million or greater; (b) an acquisition; (c) acceleration in the event of default; or (d) the fifth anniversary of the date of the note (July 2017).
	(d) In 2012, the Company purchased a "B" Note secured by a first mortgage on a class A community in West Los Angeles. The $26.5 million loan was purchased at a yield of 7.25% and bore a coupon rate of 7.00%. Interest payments are due monthly and the note is due June 2022. The discount is amortized using the effective interest method. In July 2014, the Company received proceeds of $36.0 million from the repayment of this note, resulting in a net gain of approximately $8.4 million, which is included in Interest and other income/(expense), net on the Consolidated Statements of Operations.
	During the years ended December 31, 2014, 2013 and 2012, the Company recognized $3.4 million, $4.1 million and $2.7 million, respectively, of interest income from these notes receivable, of which $0, $765,000 and $281,000, respectively, were related party interest income. Interest income is included in Interest and other income/(expense), net on the Consolidated Statements of Operations.
Marketable Securities
Investment in joint ventures	Investment in Joint Ventures and Partnerships
	We use the equity method to account for investments in joint ventures and partnerships that qualify as variable interest entities where we are not the primary beneficiary and entities that we do not control or where we do not own a majority of the economic interest but have the ability to exercise significant influence over the operating and financial policies of the investee. Throughout these financial statements we use the term “joint venture” or “partnership” when referring to investments in entities in which we do not have a 100% ownership interest. The Company also uses the equity method when we function as the managing partner and our venture partner has substantive participating rights or where we can be replaced by our venture partner as managing partner without cause. For a joint venture or partnership accounted for under the equity method, our share of net earnings or losses is reflected as income/loss when earned/incurred and distributions are credited against our investment in the joint venture or partnership as received.
	In determining whether a joint venture or partnership is a variable interest entity, the Company considers: the form of our ownership interest and legal structure; the size of our investment; the financing structure of the entity, including necessity of subordinated debt; estimates of future cash flows; ours and our partner’s ability to participate in the decision making related to acquisitions, disposition, budgeting and financing of the entity; obligation to absorb losses and preferential returns; nature of our partner’s primary operations; and the degree, if any, of disproportionality between the economic and voting interests of the entity. As of December 31, 2014, the Company did not determine any of our joint ventures or partnerships to be variable interest entities.
	We evaluate our investments in unconsolidated joint ventures for events or changes in circumstances that indicate there may be an other-than-temporary decline in value. We consider various factors to determine if a decrease in the value of the investment is other-than-temporary. These factors include, but are not limited to, age of the venture, our intent and ability to retain our investment in the entity, the financial condition and long-term prospects of the entity, the fair value of the property of the joint venture, and the relationships with the other joint venture partners and its lenders. The amount of loss recognized is the excess of the investment’s carrying amount over its estimated fair value. If we believe that the decline in fair value is temporary, no impairment is recorded. The aforementioned factors are taken into consideration as a whole by management in determining the valuation of our equity method investments. Should the actual results differ from management’s judgment, the valuation could be negatively affected and may result in a negative impact to our Consolidated Financial Statements.
Derivative financial instruments	Derivative Financial Instruments
	The Company utilizes derivative financial instruments to manage interest rate risk and generally designates these financial instruments as cash flow hedges. Derivative financial instruments are recorded on our Consolidated Balance Sheets as either an asset or liability and measured quarterly at their fair value. The changes in fair value for cash flow hedges that are deemed effective are reflected in other comprehensive income/(loss) and for non-designated derivative financial instruments in earnings. The ineffective component of cash flow hedges, if any, is recorded in earnings.
Redeemable noncontrolling interests in the Operating Partnership	Redeemable Noncontrolling Interests in the Operating Partnership
	Interests in the Operating Partnership held by limited partners are represented by Operating Partnership units (“OP Units”). The income is allocated to holders of OP Units based upon net income available to common stockholders and the weighted average number of OP Units outstanding to total common shares plus OP Units outstanding during the period. Capital contributions, distributions, and profits and losses are allocated to noncontrolling interests in accordance with the terms of the partnership agreement.
	Limited partners have the right to require the Operating Partnership to redeem all or a portion of the OP Units held by the limited partner at a redemption price equal to and in the form of the Cash Amount as defined in the Amended and Restated Agreement of Limited Partnership of the Operating Partnership (the “Operating Partnership Agreement”), provided that such OP Units have been outstanding for at least one year. UDR, as the general partner of the Operating Partnership may, in its sole discretion, purchase the OP Units by paying to the limited partner either the Cash Amount or the REIT Share Amount (generally one share of Common Stock of the Company for each OP Unit), as defined in the Operating Partnership Agreement. Accordingly, the Company records the OP Units outside of permanent equity and reports the OP Units at their redemption value using the Company’s stock price at each balance sheet date.
Income Taxes	Income Taxes
	Due to the structure of the Company as a REIT and the nature of the operations for the operating properties, no provision for federal income taxes has been provided for at UDR. Historically, the Company has generally incurred only state and local excise and franchise taxes. UDR has elected for certain consolidated subsidiaries to be treated as taxable REIT subsidiaries (“TRS”), primarily those engaged in development activities.
	Income taxes for our TRS are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rate is recognized in earnings in the period of the enactment date. The Company’s deferred tax assets are generally the result of differing depreciable lives on capitalized assets and timing of expense recognition for certain accrued liabilities. As of December 31, 2014 and 2013, UDR’s net deferred tax asset of $7.0 million, which had no valuation allowance, and $32.3 million, net of a valuation allowance of $1.3 million, respectively, was included in Other assets on the Consolidated Balance Sheets.
	Prior to 2012, our TRS had a history of losses and, as a result, historically recognized a valuation allowance for net deferred tax assets. Each quarter, the Company evaluates the need to retain all or a portion of the valuation allowance on its net deferred tax assets. In 2012, the Company determined that it was more likely than not that the deferred tax assets, including any remaining net operating loss carry forward, would be realized. In making this determination, the Company analyzed, among other things, its recent history of earnings from sales of depreciable property, forecasts of future earnings and its cumulative earnings for the last twelve quarters. The reversal of the valuation allowance resulted in an income tax benefit of $44.4 million during the year ended December 31, 2012, $21.5 million of which is reported in continuing operations and included within Tax benefit/(provision), net in the Consolidated Statements of Operations, and $22.9 million of which is included within Income/(loss) from discontinued operations, net of tax in the Consolidated Statements of Operations.
	GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition.
	The Company recognizes its tax positions and evaluates them using a two-step process. First, UDR determines whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The Company will determine the amount of benefit to recognize and record the amount that is more likely than not to be realized upon ultimate settlement.
	UDR had no material unrecognized tax benefit, accrued interest or penalties at December 31, 2014. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2010 through 2013 remain open to examination by tax jurisdictions to which we are subject. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in income tax expense.
Discontinued operations	Discontinued Operations
	Prior to the adoption of ASU No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, the results of operations for those properties sold during the year or classified as held for sale at the end of the current year are classified as discontinued operations in the current and prior periods. Further, to meet the discontinued operations criteria, the Company will not have any significant continuing involvement in the ownership or operation of the property after the sale or disposition. Once a property is classified as held for sale, depreciation is no longer recorded. However, if the Company determines that the property no longer meets the criteria for held for sale, the Company will recapture any unrecorded depreciation on the property. The assets and liabilities, if any, of properties classified as held for sale are presented separately on the Consolidated Balance Sheets at the lower of their carrying amount or their estimated fair value less the costs to sell the assets. (See Note 3, Discontinued Operations and Assets Held for Sale, for further discussion).
Stock-based employee compensation plans	Stock-Based Employee Compensation Plans
	The Company measures the cost of employee services received in exchange for an award of an equity instrument based on the award’s fair value on the grant date and recognizes the cost over the period during which the employee is required to provide service in exchange for the award, which is generally the vesting period. The fair value for stock options issued by the Company is calculated utilizing the Black-Scholes-Merton formula. For performance based awards, the Company remeasures the fair value each balance sheet date with adjustments made on a cumulative basis until the award is settled and the final compensation is known.
Advertising costs	Advertising Costs
	All advertising costs are expensed as incurred and reported on the Consolidated Statements of Operations within the line item
Cost of raising capital	Cost of Raising Capital
	Costs incurred in connection with the issuance of equity securities are deducted from stockholders’ equity. Costs incurred in connection with the issuance or renewal of debt are recorded based on the terms of the debt issuance or renewal. Accordingly, if the terms of the renewed or modified debt instrument are deemed to be substantially different (i.e. a 10 percent or greater difference in the cash flows between instruments), all unamortized financing costs associated with the extinguished debt are charged to earnings in the current period and certain costs of new debt issuances are capitalized and amortized over the term of the debt. When the cash flows are not substantially different, the lender costs associated with the renewal or modification are capitalized and amortized into interest expense over the remaining term of the related debt instrument and other related costs are expensed. The balance of any unamortized financing costs associated with retired debt is expensed upon retirement. Deferred financing costs for new debt instruments include fees and costs incurred by the Company to obtain financing. Deferred financing costs are generally amortized on a straight-line basis, which approximates the effective interest method, over a period not to exceed the term of the related debt.
Preferred Share Redemption and Repurchases	Preferred Share Redemption and Repurchases
	During the year ended December 31, 2012, the Company completed the redemption of all outstanding shares of its 6.75% Series G Cumulative Redeemable Preferred Stock. A total of 3,264,362 shares of the Series G Preferred Stock was redeemed at a redemption price of $25 per share in cash, plus accrued and unpaid dividends to the redemption date for a total cost of $82.1 million.
	When redeeming or repurchasing preferred stock, the Company recognizes share issuance costs as a charge to the preferred stock on a pro rata basis to the total costs incurred for the preferred stock as well as any premium or discount on the redemption or repurchase. In connection with the redemption of the Series G Preferred Stock, the Company recognized a (decrease)/increase in net income/(loss) attributable to common stockholders of $(2.8) million for the year ended December 31, 2012, which is reported in Premium on preferred stock redemption or repurchases, net on the Consolidated Statements of Operations.
Comprehensive income	Comprehensive Income/(Loss)
	Comprehensive income/(loss), which is defined as the change in equity during each period from transactions and other events and circumstances from nonowner sources, including all changes in equity during a period except for those resulting from investments by or distributions to stockholders, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the years ended December 31, 2014, 2013, and 2012, the Company's other comprehensive income/(loss) consisted of the gain/(loss) (effective portion) on derivative instruments that are designated as and qualify as cash flow hedges, (gain)/loss on derivative instruments and marketable securities reclassified from other comprehensive income/(loss) into earnings, and the allocation of other comprehensive income/(loss) to redeemable noncontrolling interests. The (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) is included in interest expense in the accompanying Consolidated Statements of Operations. See Note 13, Derivatives and Hedging Activity, for further discussion. The (gain)/loss on marketable securities reclassified from other comprehensive income/(loss) is included in Interest and other income/(expense), net on the Consolidated Statements of Operations. The allocation of other comprehensive income/(loss) to redeemable noncontrolling interests during the years ended December 31, 2014, 2013, and 2012 was $(133,000), $250,000, and $80,000, respectively.
Use of estimates	Use of Estimates
	The preparation of these financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates.
Market concentration risk	Market Concentration Risk
	The Company is subject to increased exposure from economic and other competitive factors specific to markets where the Company holds a significant percentage of the carrying value of its real estate portfolio. At December 31, 2014, the Company held greater than 10% of the carrying value of its real estate portfolio in the Orange County, California; Metropolitan D.C.; and New York, New York markets.

Significant_Accounting_Policie3

Significant Accounting Policies (UNITED DOMINION REALTY, L.P.) (Policies)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In April 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, which incorporates a requirement that a disposition represent a strategic shift in an entity’s operations into the definition of a discontinued operation. In accordance with the ASU, a discontinued operation represents (1) a component of an entity or group of components that has been disposed of or is classified as held for sale in a single transaction and represents a strategic shift that has or will have a major effect on an entity’s financial results, or (2) an acquired business that is classified as held for sale on the date of acquisition. A strategic shift could include a disposal of (1) a separate major line of business, (2) a separate major geographic area of operations, (3) a major equity method investment, or (4) other major parts of an entity. The standard requires prospective application and will be effective for interim and annual periods beginning on or after December 15, 2014, with early adoption permitted. The early adoption provision excludes components of an entity that were sold or classified as held for sale prior to the adoption of the standard.
	The Company elected to early adopt this standard effective January 1, 2014, which had a significant impact on the Company’s consolidated financial statements as further discussed in Note 3, Discontinued Operations. Subsequent to the Company’s adoption of ASU 2014-08, the sale of real estate that does not meet the definition of a discontinued operation under the standard is included in Gain/(loss) on sale of real estate owned, net of tax on the Consolidated Statements of Operations.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The updated standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The standard specifically excludes lease contracts. The ASU allows for the use of either the full or modified retrospective transition method, and the standard will be effective for the Company on January 1, 2017; early adoption is not permitted. The Company has not yet selected a transition method and we are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures.
Real estate	Real Estate
	Real estate assets held for investment are carried at historical cost and consist of land, buildings and improvements, furniture, fixtures and equipment and other costs incurred during their development, acquisition and redevelopment.
	Expenditures for ordinary repair and maintenance costs are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to the acquisition and/or improvement of real estate assets are capitalized and depreciated over their estimated useful lives if the expenditures qualify as a betterment or the life of the related asset will be substantially extended beyond the original life expectancy.
	UDR purchases real estate investment properties and records the tangible and identifiable intangible assets and liabilities acquired based on their estimated fair value. The primary, although not only, identifiable intangible asset associated with our portfolio is the value of existing lease agreements. When recording the acquisition of a community, we first assign fair value to the estimated intangible value of the existing lease agreements and then to the estimated value of the land, building and fixtures assuming the community is vacant. The Company estimates the intangible value of the lease agreements by determining the lost revenue associated with a hypothetical lease-up. Depreciation on the building is based on the expected useful life of the asset and the in-place leases are amortized over their remaining average contractual life. Property acquisition costs are expensed as incurred.
	Quarterly or when changes in circumstances warrant, UDR will assess our real estate properties for indicators of impairment. In determining whether the Company has indicators of impairment in our real estate assets, we assess whether the long-lived asset’s carrying value exceeds the community’s undiscounted future cash flows, which is representative of projected net operating income (“NOI”) plus the residual value of the community. Our future cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. If such indicators of impairment are present and the carrying value exceeds the undiscounted cash flows of the community, an impairment loss is recognized equal to the excess of the carrying amount of the asset over its estimated fair value. Our estimates of fair market value represent our best estimate based primarily upon unobservable inputs related to rental rates, operating costs, growth rates, discount rates, capitalization rates, industry trends and reference to market rates and transactions.
	For long-lived assets to be disposed of, impairment losses are recognized when the fair value of the asset less estimated cost to sell is less than the carrying value of the asset. Properties classified as real estate held for sale generally represent properties that are actively marketed or contracted for sale with the closing expected to occur within the next twelve months. Real estate held for sale is carried at the lower of cost, net of accumulated depreciation, or fair value, less the cost to sell, determined on an asset-by-asset basis. Expenditures for ordinary repair and maintenance costs on held for sale properties are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to held for sale properties are capitalized at cost. Depreciation is not recorded on real estate held for sale.
	Depreciation is computed on a straight-line basis over the estimated useful lives of the related assets which are 35 to 55 years for buildings, 10 to 35 years for major improvements, and 3 to 10 years for furniture, fixtures, equipment, and other assets.
	Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation. The Company capitalizes costs directly related to the predevelopment, development, and redevelopment of a capital project, which include, but are not limited to, interest, real estate taxes, insurance, and allocated development and redevelopment overhead related to support costs for personnel working on the capital projects. We use our professional judgment in determining whether such costs meet the criteria for capitalization or must be expensed as incurred. These costs are capitalized only during the period in which activities necessary to ready an asset for its intended use are in progress and such costs are incremental and identifiable to a specific activity to get the asset ready for its intended use. These costs, excluding the direct costs of development and redevelopment and capitalized interest, for the years ended December 31, 2014, 2013, and 2012 were $9.0 million, $11.1 million and $10.0 million, respectively. During the years ended December 31, 2014, 2013, and 2012, total interest capitalized was $20.2 million, $29.4 million, and $26.4 million, respectively. As each home in a capital project is completed and becomes available for lease-up, the Company ceases capitalization on the related portion and depreciation commences over the estimated useful life.
Cash and cash equivalents	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash on hand, demand deposits with financial institutions and short-term, highly liquid investments. We consider all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The majority of the Company’s cash and cash equivalents are held at major commercial banks.
Derivative financial instruments	Derivative Financial Instruments
	The Company utilizes derivative financial instruments to manage interest rate risk and generally designates these financial instruments as cash flow hedges. Derivative financial instruments are recorded on our Consolidated Balance Sheets as either an asset or liability and measured quarterly at their fair value. The changes in fair value for cash flow hedges that are deemed effective are reflected in other comprehensive income/(loss) and for non-designated derivative financial instruments in earnings. The ineffective component of cash flow hedges, if any, is recorded in earnings.
Revenue and real estate sales gain recognition	Revenue and Real Estate Sales Gain Recognition
	Rental income related to leases is recognized on an accrual basis when due from residents and tenants in accordance with GAAP. Rental payments are generally due on a monthly basis and recognized when earned. The Company recognizes interest income, management and other fees and incentives when earned, and the amounts are fixed and determinable.
	For sale transactions meeting the requirements for full accrual profit recognition, we remove the related assets and liabilities from our Consolidated Balance Sheets and record the gain or loss in the period the transaction closes. For sale transactions that do not meet the full accrual sale criteria due to our continuing involvement, we evaluate the nature of the continuing involvement and account for the transaction under an alternate method of accounting. Unless certain limited criteria are met, non-monetary transactions, including property exchanges, are accounted for at fair value.
	Sales to entities in which we retain or otherwise own an interest are accounted for as partial sales. If all other requirements for recognizing profit under the full accrual method have been satisfied and no other forms of continuing involvement are present, we recognize profit proportionate to the outside interest in the buyer and defer the gain on the interest we retain. The Company recognizes any deferred gain when the property is sold to a third party. In transactions accounted for by us as partial sales, we determine if the buyer of the majority equity interest in the venture was provided a preference as to cash flows in either an operating or a capital waterfall. If a cash flow preference has been provided, we recognize profit only to the extent that proceeds from the sale of the majority equity interest exceed costs related to the entire property.
Discontinued operations	Discontinued Operations
	Prior to the adoption of ASU No. 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, the results of operations for those properties sold during the year or classified as held for sale at the end of the current year are classified as discontinued operations in the current and prior periods. Further, to meet the discontinued operations criteria, the Company will not have any significant continuing involvement in the ownership or operation of the property after the sale or disposition. Once a property is classified as held for sale, depreciation is no longer recorded. However, if the Company determines that the property no longer meets the criteria for held for sale, the Company will recapture any unrecorded depreciation on the property. The assets and liabilities, if any, of properties classified as held for sale are presented separately on the Consolidated Balance Sheets at the lower of their carrying amount or their estimated fair value less the costs to sell the assets. (See Note 3, Discontinued Operations and Assets Held for Sale, for further discussion).
Income taxes	Income Taxes
	Due to the structure of the Company as a REIT and the nature of the operations for the operating properties, no provision for federal income taxes has been provided for at UDR. Historically, the Company has generally incurred only state and local excise and franchise taxes. UDR has elected for certain consolidated subsidiaries to be treated as taxable REIT subsidiaries (“TRS”), primarily those engaged in development activities.
	Income taxes for our TRS are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rate is recognized in earnings in the period of the enactment date. The Company’s deferred tax assets are generally the result of differing depreciable lives on capitalized assets and timing of expense recognition for certain accrued liabilities. As of December 31, 2014 and 2013, UDR’s net deferred tax asset of $7.0 million, which had no valuation allowance, and $32.3 million, net of a valuation allowance of $1.3 million, respectively, was included in Other assets on the Consolidated Balance Sheets.
	Prior to 2012, our TRS had a history of losses and, as a result, historically recognized a valuation allowance for net deferred tax assets. Each quarter, the Company evaluates the need to retain all or a portion of the valuation allowance on its net deferred tax assets. In 2012, the Company determined that it was more likely than not that the deferred tax assets, including any remaining net operating loss carry forward, would be realized. In making this determination, the Company analyzed, among other things, its recent history of earnings from sales of depreciable property, forecasts of future earnings and its cumulative earnings for the last twelve quarters. The reversal of the valuation allowance resulted in an income tax benefit of $44.4 million during the year ended December 31, 2012, $21.5 million of which is reported in continuing operations and included within Tax benefit/(provision), net in the Consolidated Statements of Operations, and $22.9 million of which is included within Income/(loss) from discontinued operations, net of tax in the Consolidated Statements of Operations.
	GAAP defines a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. GAAP also provides guidance on derecognition, classification, interest and penalties, accounting for interim periods, disclosure and transition.
	The Company recognizes its tax positions and evaluates them using a two-step process. First, UDR determines whether a tax position is more likely than not (greater than 50 percent probability) to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The Company will determine the amount of benefit to recognize and record the amount that is more likely than not to be realized upon ultimate settlement.
	UDR had no material unrecognized tax benefit, accrued interest or penalties at December 31, 2014. UDR and its subsidiaries are subject to federal income tax as well as income tax of various state and local jurisdictions. The tax years 2010 through 2013 remain open to examination by tax jurisdictions to which we are subject. When applicable, UDR recognizes interest and/or penalties related to uncertain tax positions in income tax expense.
Advertising costs	Advertising Costs
	All advertising costs are expensed as incurred and reported on the Consolidated Statements of Operations within the line item
Comprehensive income	Comprehensive Income/(Loss)
	Comprehensive income/(loss), which is defined as the change in equity during each period from transactions and other events and circumstances from nonowner sources, including all changes in equity during a period except for those resulting from investments by or distributions to stockholders, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the years ended December 31, 2014, 2013, and 2012, the Company's other comprehensive income/(loss) consisted of the gain/(loss) (effective portion) on derivative instruments that are designated as and qualify as cash flow hedges, (gain)/loss on derivative instruments and marketable securities reclassified from other comprehensive income/(loss) into earnings, and the allocation of other comprehensive income/(loss) to redeemable noncontrolling interests. The (gain)/loss on derivative instruments reclassified from other comprehensive income/(loss) is included in interest expense in the accompanying Consolidated Statements of Operations. See Note 13, Derivatives and Hedging Activity, for further discussion. The (gain)/loss on marketable securities reclassified from other comprehensive income/(loss) is included in Interest and other income/(expense), net on the Consolidated Statements of Operations. The allocation of other comprehensive income/(loss) to redeemable noncontrolling interests during the years ended December 31, 2014, 2013, and 2012 was $(133,000), $250,000, and $80,000, respectively.
Use of estimates	Use of Estimates
	The preparation of these financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates.
Market concentration risk	Market Concentration Risk
	The Company is subject to increased exposure from economic and other competitive factors specific to markets where the Company holds a significant percentage of the carrying value of its real estate portfolio. At December 31, 2014, the Company held greater than 10% of the carrying value of its real estate portfolio in the Orange County, California; Metropolitan D.C.; and New York, New York markets.
United Dominion Reality L.P.
Entity Information [Line Items]
Recent Accounting Pronouncements	Recent Accounting Pronouncements
Real estate	Real Estate
	Real estate assets held for investment are carried at historical cost and consist of land, buildings and improvements, furniture, fixtures and equipment and other costs incurred during their development, acquisition and redevelopment.
	Expenditures for ordinary repair and maintenance costs are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to the acquisition and/or improvement of real estate assets are capitalized and depreciated over their estimated useful lives if the expenditures qualify as a betterment or the life of the related asset will be substantially extended beyond the original life expectancy.
	The Operating Partnership purchases real estate investment properties and records the tangible and identifiable intangible assets and liabilities acquired based on their estimated fair value. The primary, although not only, identifiable intangible asset associated with our portfolio is the value of existing lease agreements. When recording the acquisition of a community, we first assign fair value to the estimated intangible value of the existing lease agreements and then to the estimated value of the land, building and fixtures assuming the community is vacant. The Operating Partnership estimates the intangible value of the lease agreements by determining the lost revenue associated with a hypothetical lease-up. Depreciation on the building is based on the expected useful life of the asset and the in-place leases are amortized over their remaining average contractual life. Property acquisition costs are expensed as incurred.
	Quarterly or when changes in circumstances warrant, the Operating Partnership will assess our real estate properties for indicators of impairment. In determining whether the Operating Partnership has indicators of impairment in our real estate assets, we assess whether the long-lived asset’s carrying value exceeds the community’s undiscounted future cash flows, which is representative of projected net operating income (“NOI”) plus the residual value of the community. Our future cash flow estimates are based upon historical results adjusted to reflect our best estimate of future market and operating conditions and our estimated holding periods. If such indicators of impairment are present and the carrying value exceeds the undiscounted cash flows of the community, an impairment loss is recognized equal to the excess of the carrying amount of the asset over its estimated fair value. Our estimates of fair market value represent our best estimate based primarily upon unobservable inputs related to rental rates, operating costs, growth rates, discount rates and capitalization rates, industry trends and reference to market rates and transactions.
	For long-lived assets to be disposed of, impairment losses are recognized when the fair value of the asset less estimated cost to sell is less than the carrying value of the asset. Properties classified as real estate held for sale generally represent properties that are actively marketed or contracted for sale with the closing expected to occur within the next twelve months. Real estate held for sale is carried at the lower of cost, net of accumulated depreciation, or fair value, less the cost to sell, determined on an asset-by-asset basis. Expenditures for ordinary repair and maintenance costs on held for sale properties are charged to expense as incurred. Expenditures for improvements, renovations, and replacements related to held for sale properties are capitalized at cost. Depreciation is not recorded on real estate held for sale.
	Depreciation is computed on a straight-line basis over the estimated useful lives of the related assets which are 35 to 55 years for buildings, 10 to 35 years for major improvements, and 3 to 10 years for furniture, fixtures, equipment, and other assets.
	Predevelopment, development, and redevelopment projects and related costs are capitalized and reported on the Consolidated Balance Sheets as Total real estate owned, net of accumulated depreciation. The Operating Partnership capitalizes costs directly related to the predevelopment, development, and redevelopment of a capital project, which include, but are not limited to, interest, real estate taxes, insurance, and allocated development and redevelopment overhead related to support costs for personnel working on the capital projects. We use our professional judgment in determining whether such costs meet the criteria for capitalization or must be expensed as incurred. These costs are capitalized only during the period in which activities necessary to ready an asset for its intended use are in progress and such costs are incremental and identifiable to a specific activity to get the asset ready for its intended use. These costs, excluding the direct costs of development and redevelopment and capitalized interest, for the years ended December 31, 2014, 2013, and 2012 were $2.0 million, $2.5 million, and $2.1 million, respectively. During the years ended December 31, 2014, 2013, and 2012, total interest capitalized was $2.9 million, $5.9 million, $3.7 million, respectively. As each home in a capital project is completed and becomes available for lease-up, the Operating Partnership ceases capitalization on the related portion and depreciation commences over the estimated useful life.
Cash and cash equivalents	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash on hand, demand deposits with financial institutions and short-term, highly liquid investments. We consider all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. The majority of the Operating Partnership’s cash and cash equivalents are held at major commercial banks.
Derivative financial instruments	Derivative Financial Instruments
	The General Partner utilizes derivative financial instruments to manage interest rate risk and generally designates these financial instruments as cash flow hedges. Derivative financial instruments associated with the Operating Partnership’s allocation of the General Partner’s debt are recorded on our Consolidated Balance Sheets as either an asset or liability and measured quarterly at their fair value. The changes in fair value for the General Partner’s cash flow hedges allocated to the Operating Partnership that are deemed effective are reflected in other comprehensive income and for non-designated derivative financial instruments in earnings. The ineffective component of cash flow hedges, if any, is recorded in earnings.
Non-controlling interests	Noncontrolling Interests
	The noncontrolling interests represent the General Partner’s interests in certain consolidated subsidiaries and are presented in the capital section of the Consolidated Balance Sheets since these interests are not convertible or redeemable into any other ownership interests of the Operating Partnership.
	During the year ended December 31, 2013, the Operating Partnership corrected an error in the General Partner’s ownership interest in one of the consolidated subsidiaries. The correction increased the General Partner’s ownership interest resulting in a cumulative adjustment increasing Net (income)/loss attributable to noncontrolling interests by $3.3 million on the Consolidated Statements of Operations with a corresponding increase to Noncontrolling interests on the Consolidated Balance Sheets. Management believes the impact of the cumulative adjustment in 2013 is immaterial to the financial statements taken as a whole.
	Income Tax
Revenue and real estate sales gain recognition	Revenue and Real Estate Sales Gain Recognition
	Rental income related to leases is recognized on an accrual basis when due from residents and tenants in accordance with GAAP. Rental payments are generally due on a monthly basis and recognized when earned. The Operating Partnership recognizes interest income, management and other fees and incentives when earned, fixed and determinable.
	For sale transactions meeting the requirements for full accrual profit recognition, we remove the related assets and liabilities from our Consolidated Balance Sheets and record the gain or loss in the period the transaction closes. For sale transactions that do not meet the full accrual sale criteria due to our continuing involvement, we evaluate the nature of the continuing involvement and account for the transaction under an alternate method of accounting. Unless certain limited criteria are met, non-monetary transactions, including property exchanges, are accounted for at fair value.
	Sales to entities in which we or our General Partner retain or otherwise own an interest are accounted for as partial sales. If all other requirements for recognizing profit under the full accrual method have been satisfied and no other forms of continuing involvement are present, we recognize profit proportionate to the outside interest in the buyer and defer the gain on the interest we or our General Partner retain. The Operating Partnership recognizes any deferred gain when the property is sold to a third party. In transactions accounted by us as partial sales, we determine if the buyer of the majority equity interest in the venture was provided a preference as to cash flows in either an operating or a capital waterfall. If a cash flow preference has been provided, we recognize profit only to the extent that proceeds from the sale of the majority equity interest exceed costs related to the entire property.
Discontinued operations	Discontinued Operations
	Under GAAP, the results of operations for those properties sold during the year or classified as held for sale at the end of the current year are classified as discontinued operations in the current and prior periods. Further, to meet the discontinued operations criteria, the Operating Partnership or related parties will not have any significant continuing involvement in the ownership or operation of the property after the sale or disposition. Once a property is classified as held for sale, depreciation is no longer recorded. However, if the Operating Partnership determines that the property no longer meets the criteria for held for sale, the Operating Partnership will recapture any unrecorded depreciation on the property. The assets and liabilities, if any, of properties classified as held for sale are presented separately on the Consolidated Balance Sheets at lower of their carrying amount or their estimated fair value less the costs to sell the assets. (See Note 3, Discontinued Operations and Assets Held for Sale, for further discussion).
Earnings per Operating Partnership Unit	Basic income/(loss) per OP Unit is computed by dividing net income/(loss) attributable to general and limited partner unitholders by the weighted average number of general and limited partner units (including redeemable OP Units) outstanding during the year. Diluted income/(loss) per OP Unit reflects the potential dilution that could occur if securities or other contracts to issue OP Units were exercised or converted into OP Units or resulted in the issuance of OP Units and then shared in the income/(loss) of the Operating Partnership. For the years ended December 31, 2014, 2013, and 2012, there were no dilutive instruments, and therefore, diluted income/(loss) per OP Unit and basic income/(loss) per OP Unit are the same. See Note 9, Capital Structure, for further discussion on redemption rights of OP Units.
Allocation of General and Administrative Expenses	Allocation of General and Administrative Expenses
	The Operating Partnership is charged directly for general and administrative expenses it incurs. The Operating Partnership is also charged with other general and administrative expenses that have been allocated by the General Partner to each of its subsidiaries, including the Operating Partnership, based on each subsidiary’s pro-rata portion of UDR’s total apartment homes. (See Note 6, Related Party Transactions.)
Income taxes	Income Taxes
	The taxable income or loss of the Operating Partnership is reported on the tax returns of the partners. Accordingly, no provision has been made in the accompanying financial statements for federal or state income taxes on income that is passed through to the partners. However, any state or local revenue, excise or franchise taxes that result from the operating activities of the Operating Partnership are recorded at the entity level. The Operating Partnership’s tax returns are subject to examination by federal and state taxing authorities. Net income for financial reporting purposes differs from the net income for income tax reporting purposes primarily due to temporary differences, principally real estate depreciation and the tax deferral of certain gains on property sales. The differences in depreciation result from differences in the book and tax basis of certain real estate assets and the differences in the methods of depreciation and lives of the real estate assets.
	The Operating Partnership follows the accounting guidance within GAAP, with respect to how uncertain tax positions should be recognized, measured, presented, and disclosed in the financial statements. The guidance requires the accounting and disclosure of tax positions taken or expected to be taken in the course of preparing the Operating Partnership’s tax returns to determine whether the tax positions are “more-likely-than-not” of being sustained by the applicable tax authority. Tax positions not deemed to meet the more-likely-than-not threshold would be recorded as a tax benefit or expense in the current year. Management of the Operating Partnership is required to analyze all open tax years, as defined by the statute of limitations, for all major jurisdictions, which include federal and certain states. The Operating Partnership has no examinations in progress and none are expected at this time.
	Management of the Operating Partnership has reviewed all open tax years (2010 through 2013) and major jurisdictions, and concluded there is no tax liability resulting from unrecognized tax benefits relating to uncertain income tax positions taken or expected to be taken in future tax returns.
Advertising costs	Advertising Costs
	All advertising costs are expensed as incurred and reported on the Consolidated Statements of Operations within the line item General and administrative. During the years ended December 31, 2014, 2013, and 2012, total advertising expense from continuing and discontinued operations was $2.5 million, $2.5 million, and $2.4 million, respectively.
Comprehensive income	Comprehensive Income/(Loss)
	Comprehensive income/(loss), which is defined as the change in capital during each period from transactions and other events and circumstances from nonowner sources, including all changes in capital during a period except for those resulting from investments by or distributions to partners, is displayed in the accompanying Consolidated Statements of Comprehensive Income/(Loss). For the years ended December 31, 2014, 2013, and 2012, the Operating Partnership’s other comprehensive income/(loss) consisted of the gain/(loss) (effective portion) on derivative instruments that are designated as and qualify as cash flow hedges and (gain)/loss reclassified from other comprehensive income/(loss) into earnings. The (gain)/loss reclassified from other comprehensive income/(loss) is included in Interest expense on the Consolidated Statements of Operations. See Note 8, Derivatives and Hedging Activity, for further discussion.
Use of estimates	Use of Estimates
	The preparation of these financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the dates of the financial statements and the amounts of revenues and expenses during the reporting periods. Actual amounts realized or paid could differ from those estimates.
Market concentration risk	Market Concentration Risk
	The Operating Partnership is subject to increased exposure from economic and other competitive factors specific to those markets where it holds a significant percentage of the carrying value of its real estate portfolio at December 31, 2014, the Operating Partnership held greater than 10% of the carrying value of its real estate portfolio in the Orange County, California; San Francisco, California; Metropolitan D.C.; and New York, New York markets.

IncomeLoss_Per_Share_UNITED_DO1

Income/(Loss) Per Share (UNITED DOMINION REALTY, L.P.) Income/(Loss) Per Share (UNITED DOMNION REALTY, L.P.) (Policies) (United Dominion Reality L P [Member])	12 Months Ended
	Dec. 31, 2014
United Dominion Reality L P [Member]
Earnings Per Share [Abstract]
Earnings Per Share, Policy [Policy Text Block]	Basic income/(loss) per OP Unit is computed by dividing net income/(loss) attributable to general and limited partner unitholders by the weighted average number of general and limited partner units (including redeemable OP Units) outstanding during the year. Diluted income/(loss) per OP Unit reflects the potential dilution that could occur if securities or other contracts to issue OP Units were exercised or converted into OP Units or resulted in the issuance of OP Units and then shared in the income/(loss) of the Operating Partnership. For the years ended December 31, 2014, 2013, and 2012, there were no dilutive instruments, and therefore, diluted income/(loss) per OP Unit and basic income/(loss) per OP Unit are the same. See Note 9, Capital Structure, for further discussion on redemption rights of OP Units.

Significant_Accounting_Policie4

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Notes receivable	Notes Receivable
	The following table summarizes our notes receivable, net as of December 31, 2014 and 2013 (dollars in thousands):
		Interest rate at December 31, 2014			Balance Outstanding
					December 31, 2014				December 31, 2013
	Note due June 2014 (a)				$	—			$	40,800
	Note due February 2017 (b)	10	%		11,869				14,580
	Note due July 2017 (c)	8	%		2,500				1,400
	Note due June 2022 (net of discount of $0 and $247, respectively) (d)				—				26,253
	Total notes receivable, net				$	14,369			$	83,033
Computation of basic and diluted earning per share	The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data):
		Year Ended December 31,
		2014				2013				2012
	Numerator for income/(loss) per share:
	Income/(loss) from continuing operations	$	16,260			$	2,340			$	(46,305	)
	Gain/(loss) on sale of real estate owned, net of tax	143,572				—				—
	(Income)/loss from continuing operations attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)		48				2,089
	(Income)/loss from continuing operations attributable to noncontrolling interests	3				60				(140		)
	Income/(loss) from continuing operations attributable to UDR, Inc.	154,324				2,448				(44,356		)
	Distributions to preferred stockholders - Series E (Convertible)	(3,724		)		(3,724		)		(3,724		)
	Distributions to preferred stockholders - Series G	—				—				(2,286		)
	Premium on preferred stock redemption or repurchases, net	—				—				(2,791		)
	Income/(loss) from continuing operations attributable to common stockholders	$	150,600			$	(1,276	)		$	(53,157	)
	Income/(loss) from discontinued operations, net of tax	$	10			$	43,942			$	266,608
	(Income)/loss from discontinued operations attributable to redeemable noncontrolling interests in the Operating Partnership	—				(1,578		)		(10,075		)
	Income/(loss) from discontinued operations attributable to common stockholders	$	10			$	42,364			$	256,533
	Net income/(loss) attributable to common stockholders	$	150,610			$	41,088			$	203,376
	Denominator for income/(loss) per share - basic and diluted:
	Weighted average common shares outstanding	252,707				250,684				239,482
	Non-vested restricted stock awards	(1,179		)		(715		)		(631		)
	Denominator for income/(loss) per share - basic	251,528				249,969				238,851
	Incremental shares issuable from assumed conversion of:	1,917				—				—
	Stock options and unvested resticted stock
	Denominator for income/(loss) per share - diluted	253,445				249,969				238,851
	Income/(loss) per weighted average common share - basic:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.6			$	(0.01	)		$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17				1.07
	Net income/(loss) attributable to common stockholders	$	0.6			$	0.16			$	0.85
	Income/(loss) per weighted average common share - diluted:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.59			$	(0.01	)		$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17				1.07
	Net income/(loss) attributable to common stockholders	$	0.59			$	0.16			$	0.85

Real_Estate_Owned_Tables

Real Estate Owned (Tables)	12 Months Ended
	Dec. 31, 2014
Real Estate [Abstract]
Summary of carrying amounts for real estate owned (at cost)	The following table summarizes the carrying amounts for our real estate owned (at cost) as of December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Land and land improvements	$	1,980,221		$	1,847,127
	Depreciable property — held and used:
	Building, improvements, and furniture, fixtures and equipment	6,225,406			5,876,717
	Under development:
	Land	24,584			110,769
	Building, improvements, and furniture, fixtures and equipment	153,048			356,644
	Real estate held for disposition:
	Land	—			10,751
	Building, improvements, and furniture, fixtures and equipment	—			5,969
	Real estate owned	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Real estate owned, net	$	5,948,487		$	5,999,183

Discontinued_Operations_Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
Schedule of (loss)/income from discontinued operations	The following is a summary of Income/(loss) from discontinued operations, net of tax for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Rental income	$	147		$	9,152		$	39,543
	Rental expenses	225			3,511			14,106
	Property management	4			252			1,087
	Real estate depreciation	—			1,958			8,475
	Interest and other (income)/expense, net	21			(62		)	821
	Income/(loss) attributable to disposed properties and assets held for sale	(103		)	3,493			15,054
	Net gain/(loss) on the sale of depreciable property	75			41,919			260,404
	Impairment charges	—			(2,355		)	—
	Income tax benefit/(expense)	38			885			(8,850		)
	Income/(loss) from discontinued operations, net of tax	$	10		$	43,942		$	266,608
	Income/(loss) from discontinued operations attributable to UDR, Inc.	$	10		$	42,364		$	256,533

Joint_Ventures_Tables

Joint Ventures (Tables)	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Summary of investments in unconsolidated joint ventures	The Company recognizes earnings or losses from our investments in unconsolidated joint ventures and partnerships consisting of our proportionate share of the net earnings or losses of the joint ventures and partnerships. In addition, we may earn fees for providing management services to the unconsolidated joint ventures and partnerships.
	The following table summarizes the Company’s investment in and advances to unconsolidated joint ventures and partnerships, net, which are accounted for under the equity method of accounting as of December 31, 2014 and 2013 (dollars in thousands):
	Joint Venture		Location of Properties		Number of Properties	Number of Apartment Homes			Investment at								UDR’s Ownership Interest
					2014	2014			2014				2013				2014				2013
	Operating and development:
	UDR/MetLife I (a)		Various		4 land parcels	—			$	13,306			$	47,497			15.7			%	4.5			%
	UDR/MetLife II (a)		Various		21 operating communities	4,642			431,277				327,926				50			%	50			%
	Other UDR/MetLife Joint Ventures (a)		Various		1 operating community, 3 development communities (b), 2 land parcels	1,282			134,939				36,313				50.6			%	35.8			%
	UDR/MetLife Vitruvian Park® (c)		Addison, TX		3 operating communities, 6 land parcels	1,394			80,302				79,318				50			%	50			%
	UDR/KFH (d)		Washington, D.C.		3 operating communities	660			21,596				25,919				30			%	30			%
	Texas (e)		Texas		8 operating communities	3,359			(25,901		)		(23,591		)		20			%	20			%
	Investment in and advances to unconsolidated joint ventures, net, before participating loan investment								655,519				493,382
			Location		Preferred Return	Years To Maturity			Investment at								Income From Participating Loan Investment For The Year Ended
	Participating loan investment:								2014				2013				2014		2013			2012
	Steele Creek (f)		Denver, CO		6.50%	2.8			62,707				14,273				$2,350		$156			$—
	Total investment in and advances to unconsolidated joint ventures, net								$	718,226			$	507,655
	(a)	In January 2012, the Company formed a joint venture with an unaffiliated third party to acquire 399 Fremont (land for future development) in San Francisco, California, which is included in Other UDR/MetLife Joint Ventures in the table above. At closing, UDR owned a noncontrolling interest of 92.5% in the joint venture. The Company’s total investment was $55.5 million, which consisted of its initial investment of $37.3 million and an option to exercise its right to acquire its partner’s 7.5% ownership interest in the joint venture. In October 2012, the Company exercised its option and paid $13.5 million. In January 2013, the Company subsequently acquired its partner’s 7.5% ownership interest for $4.7 million. In December 2013, the Company sold a 49% ownership interest to MetLife in the fully-entitled 399 Fremont land parcel for approximately $29.9 million. In conjunction with the sale, the Company formed a new unconsolidated real estate joint venture with MetLife, UDR/MetLife 399 Fremont, to develop a $318 million, 447-home, luxury high-rise tower on the site. Construction commenced in the first quarter 2014. As the Company recently acquired the 399 Fremont land parcel, the sale price was equivalent to the cost basis resulting in no gain or loss on the transaction. Under the terms of the partnership, the Company serves as the general partner with significant participating rights held by our partner, and has the ability to earn fees for development management, property management, asset management, and financing transactions. The UDR/MetLife 399 Fremont Joint Venture is accounted for under the equity method of accounting. Our initial investment was approximately $31.1 million.
	In June 2013 and within UDR/MetLife I, the Company exchanged with MetLife its approximately 10% ownership interest in four operating communities and paid MetLife an additional $15.6 million in cash for an increased ownership interest of approximately 35% in two high-rise operating communities, bringing UDR's ownership interest in the two high-rise operating communities to 50% each. The two high-rise operating communities are located in Denver, Colorado and San Diego, California and were subsequently contributed to UDR/MetLife II. The four operating communities in which UDR exchanged its ownership interest are located in Washington D.C.; San Francisco, California; Dallas, Texas; and Charlotte, North Carolina. UDR continues to fee manage these four operating communities.
	In March 2014, the Company sold its minority ownership interests in two operating communities located in Los Angeles, California to MetLife for cash proceeds of $3.0 million, which resulted in an immaterial gain. In April 2014, the Company increased its ownership interest in the remaining six operating communities in the UDR/MetLife I Joint Venture from 12% to 50%, and MetLife and the Company contributed the communities to the UDR/MetLife II Joint Venture. The Company paid MetLife $82.5 million for the additional ownership interests. The Company continues to fee manage the operating communities that were contributed to the UDR/MetLife II Joint Venture as well as the two operating communities in which it sold its minority ownership interests.
	In July 2014, the Company increased the ownership interest in two land sites in UDR/Metlife I to 50.1% and formed individual asset joint ventures, which are included in Other UDR/MetLife Joint Ventures in the table above. The remaining 49.9% continues to be held by our joint venture partner MetLife. The Company paid MetLife approximately $21.5 million for the additional ownership interests.
	In December 2014, the Company increased its ownership interest in one land site in the UDR/MetLife I Joint Venture to 50%. Additionally, the Company increased its ownership interest in another land site to 50.1%, which MetLife and the Company contributed to a separate joint venture and is included in Other UDR/MetLife Joint Ventures in the table above. The Company paid MetLife approximately $15.3 million for the additional ownership interests. As of December 31, 2014, the remaining assets in the UDR/MetLife I Joint Venture were comprised of three potential development land sites in which the Company has an average ownership interest of approximately 5% and one fully entitled land parcel in which the Company owns 50%.
	In December 2014, the Company sold a 49% interest in 13th and Market located in San Diego, California to MetLife for gross proceeds of $54.2 million, resulting in a gain, net of tax, of $7.2 million and a 50% interest in 3033 Wilshire in Los Angeles, California, also to MetLife for gross proceeds of $8.3 million, resulting in a loss, net of tax, of $2.2 million.
	(b)	The number of apartment homes for the communities under development presented in the table above is based on the projected number of total homes. As of December 31, 2014, no apartment homes had been completed in Other UDR/MetLife Development Joint Ventures.
	(c)	In June 2013, the Company sold a 50% interest in five partnerships (the “UDR/MetLife Vitruvian Park® Partnerships”) to MetLife for approximately $141.3 million. The transaction resulted in a gain of approximately $436,000 which the Company has deferred until the terms of the construction completion guarantee have been met. Under the terms of the UDR/MetLife Vitruvian Park® Partnerships, the Company serves as the general partner with significant participating rights held by our partner, and earns fees for property management, asset management, and financing transactions. The UDR/MetLife Vitruvian Park® Partnerships are accounted for under the equity method of accounting. Our initial investment was approximately $80.2 million, which consisted of approximately $140.0 million (50% of our net book value of the real estate at the time of the transaction) reduced by our share of the net proceeds received upon encumbering the assets of approximately $58.7 million and other operating adjustments.
	At closing, a total of $118.3 million of secured debt was placed on the two operating communities and the community under development. The debt on the two operating communities carries an interest rate of 4.0% with a term of ten years and the non-recourse construction loan on the community under development carries an interest rate of LIBOR plus 175 basis points with a term of two years and two one-year extension options. The Company has guaranteed the completion of the construction of the development. Proceeds from the construction loan will be used for completion of construction of the development. Upon completion, at its 50% ownership, the Company's pro-rata share of the undepreciated book value of the UDR/MetLife Vitruvian Park® Partnerships' real estate assets and outstanding debt will be approximately $145.0 million and $62.8 million, respectively.
	(d) UDR is a partner with an unaffiliated third party, which formed a joint venture for the investment of up to $450 million in multifamily properties located in key, high barrier to entry markets. The partners will contribute equity of $180 million of which the Company’s maximum equity will be 30% or $54 million when fully invested.
	(e) In November 2007, UDR and an unaffiliated third party formed a joint venture to own and operate 10 communities located in Texas. UDR contributed cash and property equal to 20% of the fair value of the joint venture. During the year ended December 31, 2012, the Company acquired the remaining 80% ownership interests in two communities in Austin, Texas for $11.7 million. The Company’s investment in the joint venture at December 31, 2014 and 2013 was net of deferred profits on the sale of depreciable properties to the joint venture of $23.9 million and $24.0 million, respectively.
	In January 2015, the eight communities held by the Texas joint venture were sold, generating net proceeds to UDR of $43.5 million. The Company recorded promote and fee income of $9.6 million and a gain of $59.1 million (including $24.2 million of previously deferred gains) in connection with the sale.
	(f) In October 2013, the Company entered into a participating debt financing arrangement with a third party that is developing a $108 million, 218-home, high-rise luxury community located adjacent to the Cherry Creek Mall in Denver, Colorado. Under the agreement, UDR will finance up to 85%, or approximately $92.0 million, of the development cost at an interest rate of 6.5% per annum on the outstanding debt balance. In addition, the Company has the option to purchase the community upon completion of construction and has a 50% participating interest in the profit upon the acquisition of the community or sale to a third party. The Company accounts for the arrangement consistent with an investment in real estate under the equity method of accounting.
	As of December 31, 2014, and 2013, our participating loan investment was $62.7 million and $14.3 million, respectively, which was included in Investment in and advances to unconsolidated joint ventures, net on the Consolidated Balance Sheets. We also recognized $2.4 million and $156,000 of income included in Income/(loss) from unconsolidated entities on the Consolidated Statements of Operations for the years ended December 31, 2014 and 2013, respectively.
Financial information relating to unconsolidated joint ventures operations	Combined summary financial information relating to all of the unconsolidated joint ventures and partnerships operations (not just our proportionate share), is presented below for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	As of and For the Year Ended		UDR/MetLife I			UDR/MetLife II				UDR/MetLife Vitruvian Park®				Texas				UDR/KFH				Other joint ventures			Total
	31-Dec-14
	Condensed Statements of Operations:
	Total revenues		$	727		$	152,047			$	19,376			$	—			$	19,724			$	1,579		$	193,453
	Property operating expenses		618			52,150				10,711				—				7,498				1,122			72,099
	Real estate depreciation and amortization		2,130			41,504				7,380				—				14,426				3,959			69,399
	Operating income/(loss)		(2,021		)	58,393				1,285				—				(2,200		)		(3,502		)	51,955
	Interest expense		—			(48,493		)		(4,131		)		—				(5,873		)		(94		)	(58,591		)
	Other income/(expense)		—			—				—				—				—				—			—
	Gain/(loss) on sale of real estate		—			—				—				—				—				—			—
	Income/(loss) from discontinued operations		(31,802		)	—				—				(4,229		)		—				—			(36,031		)
	Net income/(loss)		$	(33,823	)	$	9,900			$	(2,846	)		$	(4,229	)		$	(8,073	)		$	(3,596	)	$	(42,667	)
	UDR recorded income (loss) from unconsolidated entities		$	(2,955	)	$	2,814			$	(4,068	)		$	(772	)		$	(2,601	)		$	576		$	(7,006	)
	Condensed Balance Sheets:
	Total real estate, net		$	89,482		$	1,986,237			$	278,600			$	—			$	235,623			$	351,861		$	2,941,803
	Assets held for sale		1,978			—				—				214,218				—				—			216,196
	Cash and cash equivalents		1,983			15,245				6,570				—				2,507				6,239			32,544
	Other assets		(146		)	19,589				3,933				—				1,128				4,203			28,707
	Total assets		93,297			2,021,071				289,103				214,218				239,258				362,303			3,219,250
	Amount due/(from) to UDR		107			(444		)		1,960				—				531				843			2,997
	Third party debt		—			1,147,109				123,649				—				165,209				68,510			1,504,477
	Liabilities held for sale		5,110			—				—				224,596				—				—			229,706
	Accounts payable and accrued liabilities		749			17,573				6,766				—				1,396				17,851			44,335
	Total liabilities		5,966			1,164,238				132,375				224,596				167,136				87,204			1,781,515
	Total equity		$	87,331		$	856,833			$	156,728			$	(10,378	)		$	72,122			$	275,099		$	1,437,735
	UDR’s investment in unconsolidated joint ventures		$	13,306		$	431,277			$	80,302			$	(25,901	)		$	21,596			$	197,646		$	718,226
	As of and For the Year Ended		UDR/MetLife I			UDR/MetLife II				UDR/MetLife Vitruvian Park®				Texas				UDR/KFH				Other joint ventures			Total
	31-Dec-13
	Condensed Statements of Operations:
	Total revenues		$	691		$	109,926			$	7,680			$	—			$	19,221			$	5,324		$	142,842
	Property operating expenses		621			33,809				4,633				—				7,035				3,292			49,390
	Real estate depreciation and amortization		115			30,122				3,830				—				14,199				3,564			51,830
	Operating income/(loss)		(45		)	45,995				(783		)		—				(2,013		)		(1,532		)	41,622
	Interest expense		—			(37,055		)		(1,886		)		—				(5,872		)		(913		)	(45,726		)
	Other income/(expense)		—			1				—				—				—				—			1
	Income/(loss) from discontinued operations		(22,388		)	—				—				(9,584		)		—				—			(31,972		)
	Net income/(loss)		$	(22,433	)	$	8,941			$	(2,669	)		$	(9,584	)		$	(7,885	)		$	(2,445	)	$	(36,075	)
	UDR recorded income/(loss) from unconsolidated entities		$	(4,675	)	$	4,471			$	(2,851	)		$	(1,218	)		$	(2,366	)		$	6,224		$	(415	)
	Condensed Balance Sheets:
	Total real estate, net		$	90,971		$	1,476,588			$	283,878			$	—			$	249,097			$	65,133		$	2,165,667
	Assets held for sale		753,427			—				—				231,981				—				—			985,408
	Cash and cash equivalents		305			16,454				3,498				—				2,289				—			22,546
	Other assets		4,782			16,666				1,578				—				1,474				83			24,583
	Total assets		849,485			1,509,708				288,954				231,981				252,860				65,216			3,198,204
	Amount due to UDR		4,520			2,275				1,352				—				420				1,136			9,703
	Third party debt		—			877,799				120,999				—				165,209				—			1,164,007
	Liabilities held for sale		346,810			—				—				230,393				—				—			577,203
	Accounts payable and accrued liabilities		89			14,508				7,152				—				1,234				2,813			25,796
	Total liabilities		351,419			894,582				129,503				230,393				166,863				3,949			1,776,709
	Total equity		$	498,066		$	615,126			$	159,451			$	1,588			$	85,997			$	61,267		$	1,421,495
	UDR’s investment in unconsolidated joint ventures		$	47,497		$	327,926			$	79,318			$	(23,591	)		$	25,919			$	50,586		$	507,655
	For the Year Ended December 31, 2012		UDR/MetLife I			UDR/MetLife II				UDR/MetLife Vitruvian Park®				Texas				UDR/KFH				Other joint ventures			Total
	Condensed Statements of Operations:
	Total revenues		$	632		$	87,386			$	—			$	—			$	18,670			$	2,724		$	109,412
	Property operating expenses		252			25,737				—				—				6,831				1,368			34,188
	Real estate depreciation and amortization		124			32,553				—				—				16,546				1,897			51,120
	Operating income/(loss)		256			29,096				—				—				(4,707		)		(541		)	24,104
	Interest expense		—			(29,170		)		—				—				(5,890		)		(561		)	(35,621		)
	Other income/(expense)		—			(9		)		—				—				—				—			(9		)
	Income/(loss) from discontinued operations		8,609			—				—				(1,040		)		—				—			7,569
	Net income/(loss)		$	8,865		$	(83	)		$	—			$	(1,040	)		$	(10,597	)		$	(1,102	)	$	(3,957	)
	UDR recorded income/(loss) from unconsolidated entities		$	(1,750	)	$	15			$	—			$	(2,399	)		$	(3,221	)		$	(1,224	)	$	(8,579	)

Secured_Debt_and_Unsecured_Deb1

Secured Debt and Unsecured Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Secured debt instruments	The following is a summary of our secured and unsecured debt at December 31, 2014 and 2013 (dollars in thousands):
		Principal Outstanding						For the Year Ended December 31, 2014
								Weighted Average			Weighted Average		Number of Communities
		December 31,						Interest Rate			Years to Maturity		Encumbered
		2014			2013
	Secured Debt:
	Fixed Rate Debt
	Mortgage notes payable (a)	$	401,210		$	445,706		5.46	%		1.6		6
	Fannie Mae credit facilities (b)	568,086			626,667			5.12	%		4		22
	Total fixed rate secured debt	969,296			1,072,373			5.26	%		3		28
	Variable Rate Debt
	Mortgage notes payable	31,337			63,595			1.94	%		2.1		1
	Tax-exempt secured notes payable (c)	94,700			94,700			0.83	%		8.2		2
	Fannie Mae credit facilities (b)	266,196			211,409			1.6	%		5.2		7
	Total variable rate secured debt	392,233			369,704			1.44	%		5.7		10
	Total Secured Debt	1,361,529			1,442,077			4.16	%		3.8		38
	Unsecured Debt:
	Commercial Banks
	Borrowings outstanding under an unsecured credit facility due December 2017 (d) (h)	152,500			—			1.09	%		2.9
	Senior Unsecured Notes
	5.13% Medium-Term Notes due January 2014 (e)	—			184,000			—	%		—
	5.50% Medium-Term Notes due April 2014 (net of discount of $20) (e)	—			128,480			—	%		—
	5.25% Medium-Term Notes due January 2015 (net of discounts of $6 and $134, respectively) (f)	325,169			325,041			5.25	%		—
	5.25% Medium-Term Notes due January 2016	83,260			83,260			5.25	%		1
	4.25% Medium-Term Notes due June 2018 (net of discounts of $1,465 and $1,893, respectively) (h)	298,535			298,107			4.25	%		3.4
	2.17% Term Notes due June 2018 (h)	215,000			250,000			2.17	%		3.4
	1.53% Term Notes due June 2018 (h)	100,000			65,000			1.53	%		3.4
	1.31% Term Notes due June 2018 (h)	35,000			35,000			1.31	%		3.4
	3.70% Medium-Term Notes due October 2020 (net of discounts of $46 and $54, respectively) (h)	299,954			299,946			3.7	%		5.8
	4.63% Medium-Term Notes due January 2022 (net of discounts of $2,523 and $2,882, respectively) (h)	397,477			397,118			4.63	%		7
	3.75% Medium-Term Notes due July 2024 (net of discount of $990) (g) (h)	299,010			—			3.75	%		9.5
	8.50% Debentures due September 2024	15,644			15,644			8.5	%		9.7
	Other	27			30			N/A			N/A
	Total Unsecured Debt	2,221,576			2,081,626			3.81	%		4.6
	Total Debt	$	3,583,105		$	3,523,703		3.94	%		4.3
Secured credit facilities	Further information related to these credit facilities is as follows (dollars in thousands):
		December 31, 2014			31-Dec-13
	Borrowings outstanding	$	834,282		$	838,076
	Weighted average borrowings during the period ended	835,873			839,597
	Maximum daily borrowings during the period ended	837,564			841,494
	Weighted average interest rate during the period ended	4.1		%	4.2		%
	Weighted average interest rate at the end of the period	4		%	4.1		%
Aggregate maturities of secured debt	The aggregate maturities, including amortizing principal payments of secured debt, of total debt for the next five years subsequent to December 31, 2014 are as follows (dollars in thousands):
	Year		Secured Fixed Rate Debt			Secured Variable Rate Debt			Total Secured Debt			Total Unsecured Debt (a)		Total Debt
	2015		$	196,648		$	—		$	196,648		$	324,286	$	520,934
	2016		135,167			31,337			166,504			82,377		248,881
	2017		177,774			65,000			242,774			152,500		395,274
	2018		120,969			104,787			225,756			648,443		874,199
	2019		248,738			67,700			316,438			—		316,438
	Thereafter		90,000			123,409			213,409			1,013,970		1,227,379
	Total		$	969,296		$	392,233		$	1,361,529		$	2,221,576	$	3,583,105
Summary of short-term bank borrowings under bank credit facility	The following is a summary of short-term bank borrowings under UDR’s bank credit facility at December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Total revolving credit facility	$	900,000		$	900,000
	Borrowings outstanding at end of period (1)	152,500			—
	Weighted average daily borrowings during the period ended	291,761			169,844
	Maximum daily borrowings during the period ended	625,000			372,000
	Weighted average interest rate during the period ended	1.2		%	1.2		%
	Interest rate at end of the period	1.1		%	1.3		%

IncomeLoss_Per_Share_IncomeLos

Income/(Loss) Per Share Income/(Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data):
		Year Ended December 31,
		2014				2013			2012
	Numerator for income/(loss) per share:
	Income/(loss) from continuing operations	$	16,260			$	2,340		$	(46,305	)
	Gain/(loss) on sale of real estate owned, net of tax	143,572				—			—
	(Income)/loss from continuing operations attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)		48			2,089
	(Income)/loss from continuing operations attributable to noncontrolling interests	3				60			(140		)
	Income/(loss) from continuing operations attributable to UDR, Inc.	154,324				2,448			(44,356		)
	Distributions to preferred stockholders - Series E (Convertible)	(3,724		)		(3,724		)	(3,724		)
	Distributions to preferred stockholders - Series G	—				—			(2,286		)
	Premium on preferred stock redemption or repurchases, net	—				—			(2,791		)
	Income/(loss) from continuing operations attributable to common stockholders	$	150,600			$	(1,276	)	$	(53,157	)
	Income/(loss) from discontinued operations, net of tax	$	10			$	43,942		$	266,608
	(Income)/loss from discontinued operations attributable to redeemable noncontrolling interests in the Operating Partnership	—				(1,578		)	(10,075		)
	Income/(loss) from discontinued operations attributable to common stockholders	$	10			$	42,364		$	256,533
	Net income/(loss) attributable to common stockholders	$	150,610			$	41,088		$	203,376
	Denominator for income/(loss) per share - basic and diluted:
	Weighted average common shares outstanding	252,707				250,684			239,482
	Non-vested restricted stock awards	(1,179		)		(715		)	(631		)
	Denominator for income/(loss) per share - basic	251,528				249,969			238,851
	Incremental shares issuable from assumed conversion of:	1,917				—			—
	Stock options and unvested resticted stock
	Denominator for income/(loss) per share - diluted	253,445				249,969			238,851
	Income/(loss) per weighted average common share - basic:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.6			$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.6			$	0.16		$	0.85
	Income/(loss) per weighted average common share - diluted:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.59			$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—				0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.59			$	0.16		$	0.85
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	The following table sets forth the additional shares of common stock outstanding by equity instrument if converted to common stock for each of the years ended December 31, 2014, 2013, and 2012 (shares in thousands):
		Year Ended December 31,
		2014			2013			2012
	OP Units	9,247			9,337			9,411
	Preferred Stock	3,036			3,036			3,036
	Stock options and unvested restricted stock	1,917			1,584			1,361

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Stock option and restricted stock activities	A summary of UDR’s stock option and restricted stock activities during the year ended December 31, 2014 is as follows:
		Option Outstanding				Option Exercisable				Restricted Stock
		Number of		Weighted		Number of		Weighted		Number		Weighted
		Options		Average		Options		Average		of shares		Average Fair
				Exercise				Exercise				Value Per
				Price				Price				Restricted Stock
	Balance, December 31, 2013	2,430,127		$	12.63	2,430,127		$	12.63	758,745		$	23.89
	Granted	—		—		—		—		873,010		23.14
	Exercised	(164,285	)	10.06		(164,285	)	10.06		—		—
	Vested	—		—		—		—		(619,578	)	22.7
	Forfeited	—		—		—		—		(12,199	)	23.74
	Balance, December 31, 2014	2,265,842		$	12.82	2,265,842		$	12.82	999,978		$	23.98

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of taxable distributions paid per common share	Taxable distributions paid per common share were taxable as follows for the years ended December 31, 2014, 2013, and 2012:
		Year Ended December 31,
		2014			2013			2012
	Ordinary income	$	0.695		$	0.744		$	0.174
	Qualified ordinary income	0.139			—			—
	Long-term capital gain	0.105			0.114			0.186
	Unrecaptured section 1250 gain	0.076			0.067			0.515
	Total	$	1.015		$	0.925		$	0.875
Schedule of components of the provision for income taxes	The components of the provision for income taxes are as follows for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Income tax (benefit)/expense
	Current
	Federal	$	147		$	(1,030	)	$	1,961
	State	550			846			1,463
	Total current	697			(184		)	3,424
	Deferred
	Federal	20,138			(6,907		)	(21,479		)
	State	5,159			(1,190		)	(3,021		)
	Total deferred	25,297			(8,097		)	(24,500		)
	Total income tax (benefit)/expense	$	25,994		$	(8,281	)	$	(21,076	)
	Classification of income tax (benefit)/expense
	Continuing operations	$	(15,098	)	$	(7,299	)	$	(30,717	)
	Gain/(loss) on sale of real estate owned	41,087			—			—
	Discontinued operations	5			(982		)	9,641
Schedule of components of TRS deferred tax assets and liabilities	The components of our TRS deferred tax assets and liabilities are as follows for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Deferred tax assets:
	Federal and state tax attributes	$	—		$	13,069		$	1,464
	Book/tax depreciation	6,692			19,354			12,345
	Construction capitalization differences	75			—			6,635
	Investment in partnerships	—			—			3,112
	Debt and interest deductions	—			10,311			—
	Other	401			—			2,009
	Total deferred tax assets	7,168			42,734			25,565
	Valuation allowance	—			(1,310		)	(1,390		)
	Net deferred tax assets	7,168			41,424			24,175
	Deferred tax liabilities:
	Construction capitalization differences	—			(3,766		)	—
	Investment in partnerships	—			(5,080		)	—
	Other	(192		)	(305		)	—
	Total deferred tax liabilities	(192		)	(9,151		)	—
	Net deferred tax asset	$	6,976		$	32,273		$	24,175
Schedule of effective income tax rate reconciliation	Income tax benefit/(expense), net differed from the amounts computed by applying the U.S. statutory rate of 35% to pretax income/(loss) for the years ended December 31, 2014, 2013, and 2012 as follows (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Income tax (benefit)/expense
	U.S. federal income tax (benefit)/expense	$	28,819		$	(8,493	)	$	21,853
	State income tax provision	2,678			46			2,497
	Other items	(137		)	246			(1,682		)
	Conversion of certain TRS entities to REITs	(5,770		)	—			—
	Valuation allowance	404			(80		)	(43,744		)
	Total income tax (benefit)/expense	$	25,994		$	(8,281	)	$	(21,076	)

Noncontrolling_Interests_Table

Noncontrolling Interests (Tables)	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Redeemable noncontrolling interests in the Operating Partnership	The following table sets forth redeemable noncontrolling interests in the Operating Partnership for the years ended December 31, 2014 and 2013 (dollars in thousands):
		Year Ended December 31,
		2014			2013
	Redeemable noncontrolling interests in the Operating Partnership, beginning of year	$	217,597		$	223,418
	Mark-to-market adjustment to redeemable noncontrolling interests in the Operating Partnership	73,954			3,656
	Conversion of OP Units to Common Stock	(4,372		)	(1,817		)
	Net income/(loss) attributable to redeemable noncontrolling interests in the Operating Partnership	5,511			1,530
	Distributions to redeemable noncontrolling interests in the Operating Partnership	(10,077		)	(9,440		)
	Allocation of other comprehensive income/(loss)	(133		)	250
	Redeemable noncontrolling interests in the Operating Partnership, end of year	$	282,480		$	217,597
	The following sets forth net income/(loss) attributable to common stockholders and transfers from redeemable noncontrolling interests in the Operating Partnership for the following periods (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Net income/(loss) attributable to common stockholders	$	150,610		$	41,088		$	203,376
	Conversion of OP units to UDR Common Stock	4,372			1,817			529
	Change in equity from net income/(loss) attributable to common stockholders and conversion of OP units to UDR Common Stock	$	154,982		$	42,905		$	203,905

Fair_Value_of_Derivatives_and_2

Fair Value of Derivatives and Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Estimated fair values	The estimated fair values of the Company’s financial instruments either recorded or disclosed on a recurring basis as of December 31, 2014 and 2013 are summarized as follows (dollars in thousands):
						Fair Value at December 31, 2014, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2014		Fair Value Estimate at December 31, 2014		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs
						Assets or		Inputs		(Level 3)
						Liabilities		(Level 2)
						(Level 1)
	Description:
	Notes receivable (a)	$	14,369	$	14,808	$	—	$	—	$	14,808
	Derivatives - Interest rate contracts (b)	88		88		—		88		—
	Total assets	$	14,457	$	14,896	$	—	$	88	$	14,808
	Derivatives - Interest rate contracts (b)	$	10,368	$	10,368	$	—	$	10,368	$	—
	Secured debt instruments - fixed rate: (c)
	Mortgage notes payable	401,210		415,663		—		—		415,663
	Fannie Mae credit facilities	568,086		606,623		—		—		606,623
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	31,337		31,337		—		—		31,337
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	266,196		266,196		—		—		266,196
	Unsecured debt instruments (c):
	Commercial banks	152,500		152,500		—		—		152,500
	Senior unsecured notes	2,069,076		2,144,125		—		—		2,144,125
	Total liabilities	$	3,593,473	$	3,721,512	$	—	$	10,368	$	3,711,144
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	282,480	$	282,480	$	—	$	282,480	$	—
						Fair Value at December 31, 2013, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2013		Fair Value Estimate at December 31, 2013		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs (Level 3)
						Assets or		Inputs (Level 2)
						Liabilities (Level 1)
	Description:
	Notes receivable (a)	$	83,033	$	83,833	$	—	$	—	83,833
	Total assets	$	83,033	$	83,833	$	—	$	—	$	83,833
	Derivatives- Interest rate contracts (b)	$	4,965	$	4,965	$	—	$	4,965	$	—
	Secured debt instruments- fixed rate: (c)
	Mortgage notes payable	445,706		466,375		—		—		466,375
	Fannie Mae credit facilities	626,667		661,094		—		—		661,094
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	63,595		63,595		—		—		63,595
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	211,409		211,409		—		—		211,409
	Unsecured debt instruments: (c)
	Senior unsecured notes	2,081,626		2,149,003		—		—		2,149,003
	Total liabilities	$	3,528,668	$	3,651,141	$	—	$	4,965	$	3,646,176
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	217,597	$	217,597	$	—	$	217,597	$	—
	(a)	See Note 2, Significant Accounting Policies.
	(b)	See Note 13, Derivatives and Hedging Activity.
	(c)

Derivatives_and_Hedging_Activi2

Derivatives and Hedging Activity (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative [Line Items]
Offsetting Assets [Table Text Block]	The Company has elected not to offset derivative positions in the consolidated financial statements. The tables below present the effect on its financial position had the Company made the election to offset its derivative positions as of December 31, 2014 and December 31, 2013 (dollars in thousands):
	Offsetting of Derivative Assets
			Gross Amounts of Recognized Assets				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets						Net Amount
															Financial Instruments			Cash Collateral Received
	December 31, 2014		$	88			$	—			$	88			$	(27	)	$	—		$	61
	December 31, 2013		$	—			$	—			$	—			$	—		$	—		$	—
Offsetting Liabilities [Table Text Block]
	Offsetting of Derivative Liabilities
			Gross Amounts of Recognized Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Liabilities Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets						Net Amount
															Financial Instruments			Cash Collateral Posted
	December 31, 2014		$	10,368			$	—			$	10,368			$	(27	)	$	—		$	10,341
	December 31, 2013		$	4,965			$	—			$	4,965			$	—		$	—		$	4,965
Outstanding interest rate derivatives	As of December 31, 2014, the Company had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk (dollars in thousands):
	Interest Rate Derivative		Number of Instruments		Notional
	Interest rate swaps		14		$	365,000
	Interest rate caps		3		$	243,079
	Derivatives not designated as hedges are not speculative and are used to manage the Company’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings and resulted in a gain/(loss) of $(4,000), $271,000, and $290,000 for the years ended December 31, 2014, 2013, and 2012, respectively.
	As of December 31, 2014, the Company had the following outstanding derivatives that were not designated as hedges in qualifying hedging relationships (dollars in thousands):
	Product		Number of Instruments		Notional
	Interest rate caps		1		$	96,409
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet	The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2014 and 2013 (dollars in thousands):
		Asset Derivatives								Liability Derivatives
		(included in Other assets)								(included in Other liabilities)
		Fair Value at:								Fair Value at:
		December 31,				December 31,				December 31,				December 31,
		2014				2013				2014				2013
	Derivatives designated as hedging instruments:
	Interest rate products	$	86			$	—			$	10,368			$	4,965
	Derivatives not designated as hedging instruments:
	Interest rate products	$	2			$	—			$	—			$	—
Effect of Company's derivative financial instruments on Consolidated Statements of Operation	The tables below present the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	Derivatives in Cash Flow Hedging Relationships		Unrealized holding gain/(loss) Recognized in OCI												Gain/(Loss) Reclassified from Accumulated OCI into									Gain/(Loss) Recognized in Interest expense
			(Effective Portion)												Interest expense									(Ineffective Portion and Amount Excluded from Effectiveness Testing)
															(Effective Portion)
			Year ended December 31,												Year ended December 31,									Year ended December 31,
			2014				2013				2012				2014			2013			2012			2014		2013		2012
	Interest rate products		$	(8,695	)		$	(469	)		$	(4,924	)		$	(4,834	)	$	(6,851	)	$	(7,649	)	$	3	$	—	$	—
Effect of Company's derivatives not designated as hedging instruments on the Consolidated Statements of Operations
			Gain/(Loss) Recognized in
			Interest and other income/(expense), net
			Year ended December 31,
	Derivatives Not Designated as Hedging Instruments		2014				2013				2012
	Interest rate products		$	(4	)		$	271			$	290

Commitments_and_Contingencies_1

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Summary of real estate commitments	The following summarizes the Company’s real estate commitments at December 31, 2014 (dollars in thousands):
		Number of		Costs Incurred				Expected Costs			Average Ownership
		Properties		to Date (a)				to Complete (unaudited)			Stake
	Wholly-owned — under development	1		$	177,632		(b)	$	40,068		100	%
	Wholly-owned — redevelopment	1		83,778			(b)	14,222			100	%
	Joint ventures:
	Unconsolidated joint ventures	3		225,013				172,155		(c)	Various
	Participating loan investments	1		62,707			(d)	29,302		(e)	0	%
	Total			$	549,130			$	255,747
Schedule of future minimum lease payments	Future minimum lease payments as of December 31, 2014 are as follows (dollars in thousands):
		Ground				Office Space
		Leases (a)
	2015	$	5,412			$	709
	2016	5,412				124
	2017	5,412				76
	2018	5,412				76
	2019	5,412				76
	Thereafter	313,735				109
	Total	$	340,795			$	1,170
	(a)	For purposes of our ground lease contracts, the Company uses the minimum lease payment, if stated in the agreement. For ground lease agreements where there is a reset provision based on the communities appraised value or consumer price index but does not include a specified minimum lease payment, the Company uses the current rent over the remainder of the lease term.

Reportable_Segment_Tables

Reportable Segment (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations	The following table details rental income and NOI from continuing and discontinued operations for UDR’s reportable segments for the years ended December 31, 2014, 2013, and 2012, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. in the Consolidated Statements of Operations (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Reportable apartment home segment rental income
	Same-Store Communities
	West Region	$	245,803		$	231,156		$	218,268
	Mid-Atlantic Region	161,566			160,208			155,777
	Southeast Region	107,991			102,988			97,699
	Northeast Region	60,796			58,075			54,461
	Southwest Region	54,810			52,302			46,800
	Non-Mature Communities/Other	174,183			150,907			171,239
	Total segment and consolidated rental income	$	805,149		$	755,636		$	744,244
	Reportable apartment home segment NOI
	Same-Store Communities
	West Region	$	178,926		$	166,033		$	154,205
	Mid-Atlantic Region	111,762			111,643			108,490
	Southeast Region	71,528			67,264			63,122
	Northeast Region	44,897			42,350			39,377
	Southwest Region	33,725			31,927			27,878
	Non-Mature Communities/Other	115,483			94,824			111,128
	Total segment and consolidated NOI	556,321			514,041			504,200
	Reconciling items:
	Joint venture management and other fees	13,044			12,442			11,911
	Property management	(22,142		)	(20,780		)	(20,465		)
	Other operating expenses	(8,271		)	(7,136		)	(5,718		)
	Real estate depreciation and amortization	(358,154		)	(341,490		)	(350,401		)
	General and administrative	(47,800		)	(42,238		)	(43,792		)
	Casualty-related recoveries/(charges), net	(541		)	12,253			(8,495		)
	Other depreciation and amortization	(5,775		)	(6,741		)	(4,105		)
	Income/(loss) from unconsolidated entities	(7,006		)	(415		)	(8,579		)
	Interest expense	(130,454		)	(126,083		)	(138,792		)
	Interest and other income/(expense), net	11,837			4,681			2,703
	Tax benefit/(provision), net	15,136			7,299			30,282
	Gain/(loss) on sale of real estate owned, net of tax	143,647			40,449			251,554
	Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)	(1,530		)	(7,986		)
	Net (income)/loss attributable to noncontrolling interests	3			60			(140		)
	Net income/(loss) attributable to UDR, Inc.	$	154,334		$	44,812		$	212,177
Details of assets of UDR's reportable segments	The following table details the assets of UDR’s reportable segments as of December 31, 2014 and 2013 (dollars in thousands):
		December 31,			December 31,
		2014			2013
	Reportable apartment home segment assets:
	Same-Store communities:
	West Region	$	2,358,444		$	2,337,980
	Mid-Atlantic Region	1,410,156			1,395,772
	Southeast Region	786,438			785,134
	Northeast Region	746,550			738,805
	Southwest Region	440,721			434,875
	Non-mature Communities/Other	2,640,950			2,515,411
	Total segment assets	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Total segment assets — net book value	5,948,487			5,999,183
	Reconciling items:
	Cash and cash equivalents	15,224			30,249
	Restricted cash	22,340			22,796
	Deferred financing costs, net	22,686			26,924
	Notes receivable, net	14,369			83,033
	Investment in and advances to unconsolidated joint ventures, net	718,226			507,655
	Other assets	105,202			137,882
	Total consolidated assets	$	6,846,534		$	6,807,722

Unaudited_Summarized_Consolida2

Unaudited Summarized Consolidated Quarterly Financial Data Unaudited Summarized Consolidated Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Schedule of quarterly financial information	Selected consolidated quarterly financial data for the three and twelve months ended December 31, 2014 and 2013 is summarized in the table below (dollars in thousands, except per share amounts):
		Three Months Ended
		March 31,			June 30,		September 30,		December 31,
	2014
	Rental income (a)	$	194,352		$	200,959	$	203,587	$	206,104
	Income/(loss) from continuing operations	(5,195		)	4,359		10,611		6,485
	Income/(loss) from discontinued operations, net of tax	(87		)	18		79		—
	Net income/(loss) attributable to common stockholders	17,430			29,076		39,618		64,486
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	0.07		$	0.12	$	0.16	$	0.25
	Weighted average number of shares outstanding
	Basic	250,177			250,255		251,655		253,983
	Diluted	251,822			252,191		253,732		256,000
	2013
	Rental income (a)	$	181,961		$	186,285	$	187,917	$	190,321
	Income/(loss) from continuing operations	(1,162		)	4,525		2,351		(3,374		)
	Income/(loss) from discontinued operations, net of tax	853			829		884		41,376
	Net income/(loss) attributable to common stockholders	(1,199		)	4,261		2,257		35,769
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	(0.00	)	$	0.02	$	0.01	$	0.14
	Weighted average number of shares outstanding
	Basic	249,917			249,985		249,985		249,987
	Diluted	249,917			251,406		251,454		249,987
	(a)	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
	(b)	Quarterly income/(loss) per share amounts may not total to the annual amounts.

Real_Estate_Owned_UNITED_DOMIN1

Real Estate Owned (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Summary of carrying amounts for real estate owned (at cost)	The following table summarizes the carrying amounts for our real estate owned (at cost) as of December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Land and land improvements	$	1,980,221		$	1,847,127
	Depreciable property — held and used:
	Building, improvements, and furniture, fixtures and equipment	6,225,406			5,876,717
	Under development:
	Land	24,584			110,769
	Building, improvements, and furniture, fixtures and equipment	153,048			356,644
	Real estate held for disposition:
	Land	—			10,751
	Building, improvements, and furniture, fixtures and equipment	—			5,969
	Real estate owned	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Real estate owned, net	$	5,948,487		$	5,999,183
United Dominion Reality L.P.
Entity Information [Line Items]
Summary of carrying amounts for real estate owned (at cost)	The following table summarizes the carrying amounts for our real estate owned (at cost) as of December 31, 2014 and 2013 (dollars in thousands):
		December 31, 2014			December 31, 2013
	Land	$	1,008,014		$	1,004,447
	Depreciable property — held and used:
	Buildings, improvements, and furniture, fixtures and equipment	3,230,756			3,103,970
	Under development:
	Land	—			9,447
	Construction in progress	—			70,616
	Real estate owned	4,238,770			4,188,480
	Accumulated depreciation	(1,403,303		)	(1,241,574		)
	Real estate owned, net	$	2,835,467		$	2,946,906

Discontinued_Operations_UNITED1

Discontinued Operations (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Summary of income from discontinued operations	The following is a summary of Income/(loss) from discontinued operations, net of tax for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Rental income	$	147		$	9,152		$	39,543
	Rental expenses	225			3,511			14,106
	Property management	4			252			1,087
	Real estate depreciation	—			1,958			8,475
	Interest and other (income)/expense, net	21			(62		)	821
	Income/(loss) attributable to disposed properties and assets held for sale	(103		)	3,493			15,054
	Net gain/(loss) on the sale of depreciable property	75			41,919			260,404
	Impairment charges	—			(2,355		)	—
	Income tax benefit/(expense)	38			885			(8,850		)
	Income/(loss) from discontinued operations, net of tax	$	10		$	43,942		$	266,608
	Income/(loss) from discontinued operations attributable to UDR, Inc.	$	10		$	42,364		$	256,533
United Dominion Reality L.P.
Entity Information [Line Items]
Summary of income from discontinued operations	The following is a summary of income from discontinued operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Rental income	$	—		$	8,989		$	15,745
	Rental expenses	—			3,149			5,444
	Property management	—			247			432
	Real estate depreciation	—			1,935			3,320
	Income/(loss) attributable to disposed properties	—			3,658			6,549
	Net gain/(loss) on the sale of depreciable properties	—			41,518			51,094
	Income/(loss) from discontinued operations	$	—		$	45,176		$	57,643

Debt_UNITED_DOMINION_REALTY_LP1

Debt (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Secured debt instruments	The following is a summary of our secured and unsecured debt at December 31, 2014 and 2013 (dollars in thousands):
		Principal Outstanding						For the Year Ended December 31, 2014
								Weighted Average			Weighted Average			Number of Communities
		December 31,						Interest Rate			Years to Maturity			Encumbered
		2014			2013
	Secured Debt:
	Fixed Rate Debt
	Mortgage notes payable (a)	$	401,210		$	445,706		5.46	%		1.6			6
	Fannie Mae credit facilities (b)	568,086			626,667			5.12	%		4			22
	Total fixed rate secured debt	969,296			1,072,373			5.26	%		3			28
	Variable Rate Debt
	Mortgage notes payable	31,337			63,595			1.94	%		2.1			1
	Tax-exempt secured notes payable (c)	94,700			94,700			0.83	%		8.2			2
	Fannie Mae credit facilities (b)	266,196			211,409			1.6	%		5.2			7
	Total variable rate secured debt	392,233			369,704			1.44	%		5.7			10
	Total Secured Debt	1,361,529			1,442,077			4.16	%		3.8			38
	Unsecured Debt:
	Commercial Banks
	Borrowings outstanding under an unsecured credit facility due December 2017 (d) (h)	152,500			—			1.09	%		2.9
	Senior Unsecured Notes
	5.13% Medium-Term Notes due January 2014 (e)	—			184,000			—	%		—
	5.50% Medium-Term Notes due April 2014 (net of discount of $20) (e)	—			128,480			—	%		—
	5.25% Medium-Term Notes due January 2015 (net of discounts of $6 and $134, respectively) (f)	325,169			325,041			5.25	%		—
	5.25% Medium-Term Notes due January 2016	83,260			83,260			5.25	%		1
	4.25% Medium-Term Notes due June 2018 (net of discounts of $1,465 and $1,893, respectively) (h)	298,535			298,107			4.25	%		3.4
	2.17% Term Notes due June 2018 (h)	215,000			250,000			2.17	%		3.4
	1.53% Term Notes due June 2018 (h)	100,000			65,000			1.53	%		3.4
	1.31% Term Notes due June 2018 (h)	35,000			35,000			1.31	%		3.4
	3.70% Medium-Term Notes due October 2020 (net of discounts of $46 and $54, respectively) (h)	299,954			299,946			3.7	%		5.8
	4.63% Medium-Term Notes due January 2022 (net of discounts of $2,523 and $2,882, respectively) (h)	397,477			397,118			4.63	%		7
	3.75% Medium-Term Notes due July 2024 (net of discount of $990) (g) (h)	299,010			—			3.75	%		9.5
	8.50% Debentures due September 2024	15,644			15,644			8.5	%		9.7
	Other	27			30			N/A			N/A
	Total Unsecured Debt	2,221,576			2,081,626			3.81	%		4.6
	Total Debt	$	3,583,105		$	3,523,703		3.94	%		4.3
Secured credit facilities	Further information related to these credit facilities is as follows (dollars in thousands):
		December 31, 2014			31-Dec-13
	Borrowings outstanding	$	834,282		$	838,076
	Weighted average borrowings during the period ended	835,873			839,597
	Maximum daily borrowings during the period ended	837,564			841,494
	Weighted average interest rate during the period ended	4.1		%	4.2		%
	Weighted average interest rate at the end of the period	4		%	4.1		%
Aggregate maturities of secured debt	The aggregate maturities, including amortizing principal payments of secured debt, of total debt for the next five years subsequent to December 31, 2014 are as follows (dollars in thousands):
	Year		Secured Fixed Rate Debt			Secured Variable Rate Debt			Total Secured Debt				Total Unsecured Debt (a)			Total Debt
	2015		$	196,648		$	—		$	196,648			$	324,286		$	520,934
	2016		135,167			31,337			166,504				82,377			248,881
	2017		177,774			65,000			242,774				152,500			395,274
	2018		120,969			104,787			225,756				648,443			874,199
	2019		248,738			67,700			316,438				—			316,438
	Thereafter		90,000			123,409			213,409				1,013,970			1,227,379
	Total		$	969,296		$	392,233		$	1,361,529			$	2,221,576		$	3,583,105
United Dominion Reality L.P.
Entity Information [Line Items]
Secured debt instruments	Secured debt consists of the following as of December 31, 2014 and 2013 (dollars in thousands):
		Principal Outstanding						For the Year Ended December 31, 2014
		December 31,						Weighted Average			Weighted Average			Number of Communities
		2014			2013			Interest Rate			Years to Maturity			Encumbered
	Fixed Rate Debt
	Mortgage notes payable	$	378,371		$	386,803		5.47	%		1.6			5
	Fannie Mae credit facilities	333,828			379,003			4.9	%		4.6			10
	Total fixed rate secured debt	712,199			765,806			5.2	%		3			15
	Variable Rate Debt
	Tax-exempt secured note payable	27,000			27,000			0.93	%		17.2			1
	Fannie Mae credit facilities	192,760			142,059			1.83	%		6			5
	Total variable rate secured debt	219,760			169,059			1.72	%		7.4			6
	Total secured debt	$	931,959		$	934,865		4.38	%		4			21
Secured credit facilities	The following is information related to the credit facilities allocated to the Operating Partnership (dollars in thousands):
		December 31, 2014			December 31, 2013
	Borrowings outstanding	$	526,588		$	521,062
	Weighted average borrowings during the period ended	527,592			522,007
	Maximum daily borrowings during the period ended	528,659			523,187
	Weighted average interest rate during the period ended	4.1		%	4.2		%
	Interest rate at the end of the period	4		%	4.1		%
Aggregate maturities of secured debt	The aggregate maturities of the Operating Partnership’s secured debt due during each of the next five calendar years subsequent to December 31, 2014 are as follows (dollars in thousands):
		Fixed						Variable
		Mortgage			Secured Credit			Tax-Exempt				Secured Credit			Total
		Notes Payable			Facilities			Secured Notes Payable				Facilities
	2015	$	192,637		$	366		$	—			$	—		$	193,003
	2016	130,951			385			—				—			131,336
	2017	913			15,640			—				6,566			23,119
	2018	968			111,052			—				96,974			208,994
	2019	52,902			123,096			—				—			175,998
	Thereafter	—			83,289			27,000				89,220			199,509
	Total	$	378,371		$	333,828		$	27,000			$	192,760		$	931,959

Fair_Value_of_Derivatives_and_3

Fair Value of Derivatives and Financial Instruments (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Estimated fair values	The estimated fair values of the Company’s financial instruments either recorded or disclosed on a recurring basis as of December 31, 2014 and 2013 are summarized as follows (dollars in thousands):
						Fair Value at December 31, 2014, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2014		Fair Value Estimate at December 31, 2014		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs
						Assets or		Inputs		(Level 3)
						Liabilities		(Level 2)
						(Level 1)
	Description:
	Notes receivable (a)	$	14,369	$	14,808	$	—	$	—	$	14,808
	Derivatives - Interest rate contracts (b)	88		88		—		88		—
	Total assets	$	14,457	$	14,896	$	—	$	88	$	14,808
	Derivatives - Interest rate contracts (b)	$	10,368	$	10,368	$	—	$	10,368	$	—
	Secured debt instruments - fixed rate: (c)
	Mortgage notes payable	401,210		415,663		—		—		415,663
	Fannie Mae credit facilities	568,086		606,623		—		—		606,623
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	31,337		31,337		—		—		31,337
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	266,196		266,196		—		—		266,196
	Unsecured debt instruments (c):
	Commercial banks	152,500		152,500		—		—		152,500
	Senior unsecured notes	2,069,076		2,144,125		—		—		2,144,125
	Total liabilities	$	3,593,473	$	3,721,512	$	—	$	10,368	$	3,711,144
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	282,480	$	282,480	$	—	$	282,480	$	—
						Fair Value at December 31, 2013, Using
		Total Carrying Amount in Statement of Financial Position at December 31, 2013		Fair Value Estimate at December 31, 2013		Quoted Prices in		Significant		Significant
						Active Markets		Other		Unobservable
						for Identical		Observable		Inputs (Level 3)
						Assets or		Inputs (Level 2)
						Liabilities (Level 1)
	Description:
	Notes receivable (a)	$	83,033	$	83,833	$	—	$	—	83,833
	Total assets	$	83,033	$	83,833	$	—	$	—	$	83,833
	Derivatives- Interest rate contracts (b)	$	4,965	$	4,965	$	—	$	4,965	$	—
	Secured debt instruments- fixed rate: (c)
	Mortgage notes payable	445,706		466,375		—		—		466,375
	Fannie Mae credit facilities	626,667		661,094		—		—		661,094
	Secured debt instruments- variable rate: (c)
	Mortgage notes payable	63,595		63,595		—		—		63,595
	Tax-exempt secured notes payable	94,700		94,700		—		—		94,700
	Fannie Mae credit facilities	211,409		211,409		—		—		211,409
	Unsecured debt instruments: (c)
	Senior unsecured notes	2,081,626		2,149,003		—		—		2,149,003
	Total liabilities	$	3,528,668	$	3,651,141	$	—	$	4,965	$	3,646,176
	Redeemable noncontrolling interests in the Operating Partnership (d)	$	217,597	$	217,597	$	—	$	217,597	$	—
	(a)	See Note 2, Significant Accounting Policies.
	(b)	See Note 13, Derivatives and Hedging Activity.
	(c)
United Dominion Reality L.P.
Entity Information [Line Items]
Estimated fair values	The estimated fair values of the Operating Partnership’s financial instruments either recorded or disclosed on a recurring basis as of December 31, 2014 and 2013 are summarized as follows (dollars in thousands):
						Fair Value at December 31, 2014, Using
		Total Carrying Amount in Statement of Financial Position at		Fair Value Estimate at		Quoted Prices in		Significant Other		Significant
						Active Markets		Observable		Unobservable
						for Identical		Inputs		Inputs
						Assets or		(Level 2)		(Level 3)
						Liabilities
		December 31, 2014		December 31, 2014		(Level 1)
	Description:
	Derivatives- Interest rate contracts (a)	$	39	$	39	$	—	$	39	$	—
	Total assets	$	39	$	39	$	—	$	39	$	—
	Derivatives - Interest rate contracts (a)	$	918	$	918	$	—	$	918	$	—
	Secured debt instruments - fixed rate: (b)
	Mortgage notes payable	378,371		391,835		—		—		391,835
	Fannie Mae credit facilities	333,828		355,470		—		—		355,470
	Secured debt instruments - variable rate: (b)
	Tax-exempt secured notes payable	27,000		27,000		—		—		27,000
	Fannie Mae credit facilities	192,760		192,760		—		—		192,760
	Total liabilities	$	932,877	$	967,983	$	—	$	918	$	967,065
						Fair Value at December 31, 2013, Using
		Total Carrying Amount in Statement of Financial Position at		Fair Value Estimate at		Quoted Prices in		Significant Other		Significant
						Active Markets		Observable		Unobservable
						for Identical		Inputs		Inputs
						Assets or		(Level 2)		(Level 3)
						Liabilities
		December 31, 2013		December 31, 2013		(Level 1)
	Description:
	Derivatives- Interest rate contracts (a)	$	2,731	$	2,731	$	—	$	2,731	$	—
	Secured debt instruments - fixed rate: (b)
	Mortgage notes payable	386,803		403,695		—		—		403,695
	Fannie Mae credit facilities	379,003		394,239		—		—		394,239
	Secured debt instruments - variable rate: (b)
	Tax-exempt secured notes payable	27,000		27,000		—		—		27,000
	Fannie Mae credit facilities	142,059		142,059		—		—		142,059
	Total liabilities	$	937,596	$	969,724	$	—	$	2,731	$	966,993
	(a)	See Note 8, Derivatives and Hedging Activity.
	(b)	See Note 5, Debt.

Derivatives_and_Hedging_Activi3

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Offsetting Assets [Table Text Block]	The Company has elected not to offset derivative positions in the consolidated financial statements. The tables below present the effect on its financial position had the Company made the election to offset its derivative positions as of December 31, 2014 and December 31, 2013 (dollars in thousands):
	Offsetting of Derivative Assets
			Gross Amounts of Recognized Assets				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets								Net Amount
															Financial Instruments				Cash Collateral Received
	December 31, 2014		$	88			$	—			$	88			$	(27	)		$	—			$	61
	December 31, 2013		$	—			$	—			$	—			$	—			$	—			$	—
Outstanding interest rate derivatives	As of December 31, 2014, the Company had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk (dollars in thousands):
	Interest Rate Derivative		Number of Instruments		Notional
	Interest rate swaps		14		$	365,000
	Interest rate caps		3		$	243,079
	Derivatives not designated as hedges are not speculative and are used to manage the Company’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings and resulted in a gain/(loss) of $(4,000), $271,000, and $290,000 for the years ended December 31, 2014, 2013, and 2012, respectively.
	As of December 31, 2014, the Company had the following outstanding derivatives that were not designated as hedges in qualifying hedging relationships (dollars in thousands):
	Product		Number of Instruments		Notional
	Interest rate caps		1		$	96,409
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet	The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2014 and 2013 (dollars in thousands):
		Asset Derivatives								Liability Derivatives
		(included in Other assets)								(included in Other liabilities)
		Fair Value at:								Fair Value at:
		December 31,				December 31,				December 31,				December 31,
		2014				2013				2014				2013
	Derivatives designated as hedging instruments:
	Interest rate products	$	86			$	—			$	10,368			$	4,965
	Derivatives not designated as hedging instruments:
	Interest rate products	$	2			$	—			$	—			$	—
Effect of Company's derivative financial instruments on Consolidated Statements of Operation	The tables below present the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	Derivatives in Cash Flow Hedging Relationships		Unrealized holding gain/(loss) Recognized in OCI												Gain/(Loss) Reclassified from Accumulated OCI into											Gain/(Loss) Recognized in Interest expense
			(Effective Portion)												Interest expense											(Ineffective Portion and Amount Excluded from Effectiveness Testing)
															(Effective Portion)
			Year ended December 31,												Year ended December 31,											Year ended December 31,
			2014				2013				2012				2014				2013				2012			2014		2013		2012
	Interest rate products		$	(8,695	)		$	(469	)		$	(4,924	)		$	(4,834	)		$	(6,851	)		$	(7,649	)	$	3	$	—	$	—
Effect of Company's derivatives not designated as hedging instruments on the Consolidated Statements of Operations
			Gain/(Loss) Recognized in
			Interest and other income/(expense), net
			Year ended December 31,
	Derivatives Not Designated as Hedging Instruments		2014				2013				2012
	Interest rate products		$	(4	)		$	271			$	290
Offsetting Liabilities [Table Text Block]
	Offsetting of Derivative Liabilities
			Gross Amounts of Recognized Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Liabilities Presented in the Consolidated Balance Sheets (a)				Gross Amounts Not Offset in the Consolidated Balance Sheets								Net Amount
															Financial Instruments				Cash Collateral Posted
	December 31, 2014		$	10,368			$	—			$	10,368			$	(27	)		$	—			$	10,341
	December 31, 2013		$	4,965			$	—			$	4,965			$	—			$	—			$	4,965
United Dominion Reality L.P.
Entity Information [Line Items]
Offsetting Assets [Table Text Block]	The General Partner has elected not to offset derivative positions in the consolidated financial statements. The table below presents the effect on the Operating Partnership's financial position had the General Partner made the election to offset its derivative positions as of December 31, 2014 and December 31, 2013:
	Offsetting of Derivative Assets
															Gross Amounts Not Offset in the Consolidated Balance Sheets
			Gross Amounts of Recognized Assets				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Assets Presented in the Consolidated Balance Sheets (a)				Financial Instruments				Cash Collateral Received				Net Amount
	December 31, 2014		$	39			$	—			$	39			$	—			$	—			$	39
	December 31, 2013		$	—			$	—			$	—			$	—			$	—			$	—
Outstanding interest rate derivatives	As of December 31, 2014, the Operating Partnership had the following outstanding interest rate derivatives designated as cash flow hedges of interest rate risk (dollars in thousands):
	Interest Rate Derivative		Number of Instruments		Notional
	Interest rate swaps		1		$	46,272
	Interest rate caps		2		$	166,341
	Derivatives not designated as hedges are not speculative and are used to manage the Operating Partnership’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of GAAP. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings and resulted in losses of $3,000, $9,000, and $9,000 for the years ended December 31, 2014, 2013, and 2012, respectively.
	As of December 31, 2014, we had the following outstanding derivatives that were not designated as hedges in qualifying hedging relationships (dollars in thousands):
	Product		Number of Instruments		Notional
	Interest rate caps		1		$	89,220
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet	The table below presents the fair value of the Operating Partnership’s derivative financial instruments as well as their classification on the Consolidated Balance Sheets as of December 31, 2014 and 2013 (dollars in thousands):
		Asset Derivatives								Liability Derivatives
		(included in Other assets)								(Included in Other liabilities)
		Fair Value at:								Fair Value at:
		December 31,				December 31,				December 31,				December 31,
		2014				2013				2014				2013
	Derivatives designated as hedging instruments:
	Interest rate products	$	37			$	—			$	918			$	2,731
	Derivatives not designated as hedging instruments:
	Interest rate products	$	2			$	—			$	—			$	—
Effect of Company's derivative financial instruments on Consolidated Statements of Operation	The tables below present the effect of the derivative financial instruments on the Consolidated Statements of Operations for the years ended December 31, 2014, 2013, and 2012 (dollars in thousands):
	Derivatives in Cash Flow Hedging Relationships		Unrealized holding gain/(loss) Recognized in OCI										Gain/(Loss) Reclassified from Accumulated OCI into
			(Effective Portion)										Interest expense
													(Effective Portion)
			Year ended December 31,										Year ended December 31,
			2014				2013				2012		2014				2013				2012
	Interest rate products		$	(285	)		$	(348	)		($1,898)		$	(2,275	)		$	(2,652	)		$	(3,431	)
Effect of Company's derivatives not designated as hedging instruments on the Consolidated Statements of Operations
	Derivatives Not Designated as Hedging Instruments		Gain/(Loss) Recognized in
			Interest and other income/(expense), net
			Year ended December 31,
			2014				2013				2012
	Interest rate products		$	(3	)		$	(9	)		$	(9	)
Offsetting Liabilities [Table Text Block]
	Offsetting of Derivative Liabilities
															Gross Amounts Not Offset in the Consolidated Balance Sheets
			Gross Amounts of Recognized Liabilities				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amounts of Liabilities Presented in the Consolidated Balance Sheets (b)				Financial Instruments				Cash Collateral Posted				Net Amount
	December 31, 2014		$	918			$	—			$	918			$	—			$	—			$	918
	December 31, 2013		$	2,731			$	—			$	2,731			$	—			$	—			$	2,731
	(b) Amounts reconcile to the aggregate fair value of derivative liabilities in the “Tabular Disclosure of Fair Values of Derivative Instruments on the Balance Sheet” located in this footnote.

Capital_Structure_UNITED_DOMIN1

Capital Structure (UNITED DOMINION REALTY, L.P.) Capital Structure (UNITED DOMINION REALTY, L.P.) (Tables) (United Dominion Reality L.P.)	12 Months Ended
	Dec. 31, 2014
United Dominion Reality L.P.
Entity Information [Line Items]
Schedule of OP Unit activity and OP units outstanding	The following table shows OP Units outstanding and OP Unit activity as of and for the years ended December 31, 2014, 2013, and 2012:
					UDR, Inc.
		Class A Limited	Limited		Limited		General	Total
		Partner	Partners		Partner		Partner
	Ending balance at December 31, 2011	1,751,671	7,669,632		174,749,068		110,883	184,281,254
	OP redemptions for cash	—	(5,646	)	5,646		—	—
	OP redemptions for UDR stock	—	(20,438	)	20,438		—	—
	Ending balance at December 31, 2012	1,751,671	7,643,548		174,775,152		110,883	184,281,254
	OP Units redeemed for the distribution of real estate to the General partner (a)	—	—		(1,002,556	)	—	(1,002,556	)
	OP redemptions for UDR stock	—	(76,295	)	76,295		—	—
	Ending balance at December 31, 2013	1,751,671	7,567,253		173,848,891		110,883	183,278,698
	OP redemptions for UDR stock	—	(153,451	)	153,451		—	—
	Ending balance at December 31, 2014	1,751,671	7,413,802		174,002,342		110,883	183,278,698

Commitments_and_Contingencies_2

Commitments and Contingencies (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Summary of real estate commitments	The following summarizes the Company’s real estate commitments at December 31, 2014 (dollars in thousands):
		Number of	Costs Incurred			Expected Costs			Average Ownership
		Properties	to Date (a)			to Complete (unaudited)			Stake
	Wholly-owned — under development	1	$	177,632	(b)	$	40,068		100	%
	Wholly-owned — redevelopment	1	83,778		(b)	14,222			100	%
	Joint ventures:
	Unconsolidated joint ventures	3	225,013			172,155		(c)	Various
	Participating loan investments	1	62,707		(d)	29,302		(e)	0	%
	Total		$	549,130		$	255,747

Reportable_Segments_UNITED_DOM1

Reportable Segments (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations	The following table details rental income and NOI from continuing and discontinued operations for UDR’s reportable segments for the years ended December 31, 2014, 2013, and 2012, and reconciles NOI to Net income/(loss) attributable to UDR, Inc. in the Consolidated Statements of Operations (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Reportable apartment home segment rental income
	Same-Store Communities
	West Region	$	245,803		$	231,156		$	218,268
	Mid-Atlantic Region	161,566			160,208			155,777
	Southeast Region	107,991			102,988			97,699
	Northeast Region	60,796			58,075			54,461
	Southwest Region	54,810			52,302			46,800
	Non-Mature Communities/Other	174,183			150,907			171,239
	Total segment and consolidated rental income	$	805,149		$	755,636		$	744,244
	Reportable apartment home segment NOI
	Same-Store Communities
	West Region	$	178,926		$	166,033		$	154,205
	Mid-Atlantic Region	111,762			111,643			108,490
	Southeast Region	71,528			67,264			63,122
	Northeast Region	44,897			42,350			39,377
	Southwest Region	33,725			31,927			27,878
	Non-Mature Communities/Other	115,483			94,824			111,128
	Total segment and consolidated NOI	556,321			514,041			504,200
	Reconciling items:
	Joint venture management and other fees	13,044			12,442			11,911
	Property management	(22,142		)	(20,780		)	(20,465		)
	Other operating expenses	(8,271		)	(7,136		)	(5,718		)
	Real estate depreciation and amortization	(358,154		)	(341,490		)	(350,401		)
	General and administrative	(47,800		)	(42,238		)	(43,792		)
	Casualty-related recoveries/(charges), net	(541		)	12,253			(8,495		)
	Other depreciation and amortization	(5,775		)	(6,741		)	(4,105		)
	Income/(loss) from unconsolidated entities	(7,006		)	(415		)	(8,579		)
	Interest expense	(130,454		)	(126,083		)	(138,792		)
	Interest and other income/(expense), net	11,837			4,681			2,703
	Tax benefit/(provision), net	15,136			7,299			30,282
	Gain/(loss) on sale of real estate owned, net of tax	143,647			40,449			251,554
	Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)	(1,530		)	(7,986		)
	Net (income)/loss attributable to noncontrolling interests	3			60			(140		)
	Net income/(loss) attributable to UDR, Inc.	$	154,334		$	44,812		$	212,177
Details of assets of UDR's reportable segments	The following table details the assets of UDR’s reportable segments as of December 31, 2014 and 2013 (dollars in thousands):
		December 31,			December 31,
		2014			2013
	Reportable apartment home segment assets:
	Same-Store communities:
	West Region	$	2,358,444		$	2,337,980
	Mid-Atlantic Region	1,410,156			1,395,772
	Southeast Region	786,438			785,134
	Northeast Region	746,550			738,805
	Southwest Region	440,721			434,875
	Non-mature Communities/Other	2,640,950			2,515,411
	Total segment assets	8,383,259			8,207,977
	Accumulated depreciation	(2,434,772		)	(2,208,794		)
	Total segment assets — net book value	5,948,487			5,999,183
	Reconciling items:
	Cash and cash equivalents	15,224			30,249
	Restricted cash	22,340			22,796
	Deferred financing costs, net	22,686			26,924
	Notes receivable, net	14,369			83,033
	Investment in and advances to unconsolidated joint ventures, net	718,226			507,655
	Other assets	105,202			137,882
	Total consolidated assets	$	6,846,534		$	6,807,722
United Dominion Reality L.P.
Entity Information [Line Items]
Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations	The following table details rental income and NOI from continuing and discontinued operations for the Operating Partnership’s reportable segments for the years ended December 31, 2014, 2013, and 2012, and reconciles NOI to Net income/(loss) attributable to OP unitholders in the Consolidated Statements of Operations (dollars in thousands):
		Year Ended December 31,
		2014			2013			2012
	Reportable apartment home segment rental income
	Same-Store Communities
	West Region	$	194,105		$	181,935		$	172,096
	Mid-Atlantic Region	68,822			68,205			66,487
	Northeast Region	38,087			36,623			34,579
	Southeast Region	45,224			43,208			40,771
	Southwest Region	26,580			25,614			23,980
	Non-Mature Communities/Other	49,816			55,257			62,778
	Total segment and consolidated rental income	$	422,634		$	410,842		$	400,691
	Reportable apartment home segment NOI
	Same-Store Communities
	West Region	$	142,388		$	131,276		$	122,477
	Mid-Atlantic Region	46,639			46,770			45,801
	Northeast Region	28,930			27,149			25,653
	Southeast Region	29,815			28,105			26,510
	Southwest Region	16,821			16,057			14,738
	Non-Mature Communities/Other	35,720			38,178			46,359
	Total segment and consolidated NOI	300,313			287,535			281,538
	Reconciling items:
	Property management	(11,622		)	(11,298		)	(11,019		)
	Other operating expenses	(5,172		)	(5,728		)	(5,272		)
	Real estate depreciation and amortization	(179,176		)	(181,302		)	(195,051		)
	General and administrative	(28,541		)	(24,808		)	(26,204		)
	Casualty-related recoveries/(charges), net	(541		)	8,083			(5,518		)
	Interest expense	(41,717		)	(36,058		)	(45,234		)
	Gain/(loss) on sale of real estate owned, net of tax	63,635			41,518			51,094
	Net income/(loss) attributable to noncontrolling interests	(952		)	(4,566		)	(352		)
	Net income/(loss) attributable to OP unitholders	$	96,227		$	73,376		$	43,982
Details of assets of UDR's reportable segments	The following table details the assets of the Operating Partnership’s reportable segments as of December 31, 2014 and 2013 (dollars in thousands):
		December 31,			December 31, 2013
		2014
	Reportable apartment home segment assets
	Same-Store Communities
	West Region	$	1,749,494		$	1,733,144
	Mid-Atlantic Region	713,093			706,447
	Northeast Region	447,269			443,483
	Southeast Region	333,428			328,150
	Southwest Region	228,996			226,252
	Non-Mature Communities/Other	766,490			751,004
	Total segment assets	4,238,770			4,188,480
	Accumulated depreciation	(1,403,303		)	(1,241,574		)
	Total segment assets - net book value	2,835,467			2,946,906
	Reconciling items:
	Cash and cash equivalents	502			1,897
	Restricted cash	13,811			13,526
	Deferred financing costs, net	4,475			5,848
	Other assets	24,029			25,064
	Total consolidated assets	$	2,878,284		$	2,993,241

Unaudited_Summarized_Consolida3

Unaudited Summarized Consolidated Quarterly Financial Data (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Entity Information [Line Items]
Schedule of quarterly financial information	Selected consolidated quarterly financial data for the three and twelve months ended December 31, 2014 and 2013 is summarized in the table below (dollars in thousands, except per share amounts):
		Three Months Ended
		March 31,			June 30,		September 30,		December 31,
	2014
	Rental income (a)	$	194,352		$	200,959	$	203,587	$	206,104
	Income/(loss) from continuing operations	(5,195		)	4,359		10,611		6,485
	Income/(loss) from discontinued operations, net of tax	(87		)	18		79		—
	Net income/(loss) attributable to common stockholders	17,430			29,076		39,618		64,486
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	0.07		$	0.12	$	0.16	$	0.25
	Weighted average number of shares outstanding
	Basic	250,177			250,255		251,655		253,983
	Diluted	251,822			252,191		253,732		256,000
	2013
	Rental income (a)	$	181,961		$	186,285	$	187,917	$	190,321
	Income/(loss) from continuing operations	(1,162		)	4,525		2,351		(3,374		)
	Income/(loss) from discontinued operations, net of tax	853			829		884		41,376
	Net income/(loss) attributable to common stockholders	(1,199		)	4,261		2,257		35,769
	Income/(loss) attributable to common stockholders per weighted average common share (b):
	Basic and diluted	$	(0.00	)	$	0.02	$	0.01	$	0.14
	Weighted average number of shares outstanding
	Basic	249,917			249,985		249,985		249,987
	Diluted	249,917			251,406		251,454		249,987
	(a)	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
	(b)	Quarterly income/(loss) per share amounts may not total to the annual amounts.
United Dominion Reality L.P.
Entity Information [Line Items]
Schedule of quarterly financial information	Selected consolidated quarterly financial data for the years ended December 31, 2014 and 2013 is summarized in the table blow (dollars in thousands, except per share amounts):
		Three Months Ended
		March 31,			June 30,		September 30,		December 31,
	2014
	Rental income (a)	$	102,370		$	104,842	$	107,444	$	107,978
	Income/(loss) from continuing operations	6,411			8,319		8,875		9,939
	Income/(loss) attributable to OP unitholders	30,533			24,426		8,637		32,631
	Income/(loss) attributable to OP unitholders per weighted average OP Unit — basic and diluted (b)	$	0.17		$	0.13	$	0.05	$	0.18
	2013
	Rental income (a)	$	97,770		$	100,421	$	101,558	$	102,104
	Income/(loss) from continuing operations	6,870			9,339		10,069		6,488
	Income/(loss) from discontinued operations	905			882		982		42,407
	Income/(loss) attributable to OP unitholders	7,729			10,154		11,011		44,482
	Income/(loss) attributable to OP unitholders per weighted average OP Unit — basic and diluted (b)	$	0.04		$	0.06	$	0.06	$	0.24
	(a)	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
	(b)	Quarterly income/(loss) per OP Unit amounts may not total to the annual amounts

IncomeLoss_Per_Share_UNITED_DO2

Income/(Loss) Per Share (UNITED DOMINION REALTY, L.P.) (Tables)	12 Months Ended
	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table sets forth the computation of basic and diluted income/(loss) per share for the periods presented (dollars and shares in thousands, except per share data):
		Year Ended December 31,
		2014			2013			2012
	Numerator for income/(loss) per share:
	Income/(loss) from continuing operations	$	16,260		$	2,340		$	(46,305	)
	Gain/(loss) on sale of real estate owned, net of tax	143,572			—			—
	(Income)/loss from continuing operations attributable to redeemable noncontrolling interests in the Operating Partnership	(5,511		)	48			2,089
	(Income)/loss from continuing operations attributable to noncontrolling interests	3			60			(140		)
	Income/(loss) from continuing operations attributable to UDR, Inc.	154,324			2,448			(44,356		)
	Distributions to preferred stockholders - Series E (Convertible)	(3,724		)	(3,724		)	(3,724		)
	Distributions to preferred stockholders - Series G	—			—			(2,286		)
	Premium on preferred stock redemption or repurchases, net	—			—			(2,791		)
	Income/(loss) from continuing operations attributable to common stockholders	$	150,600		$	(1,276	)	$	(53,157	)
	Income/(loss) from discontinued operations, net of tax	$	10		$	43,942		$	266,608
	(Income)/loss from discontinued operations attributable to redeemable noncontrolling interests in the Operating Partnership	—			(1,578		)	(10,075		)
	Income/(loss) from discontinued operations attributable to common stockholders	$	10		$	42,364		$	256,533
	Net income/(loss) attributable to common stockholders	$	150,610		$	41,088		$	203,376
	Denominator for income/(loss) per share - basic and diluted:
	Weighted average common shares outstanding	252,707			250,684			239,482
	Non-vested restricted stock awards	(1,179		)	(715		)	(631		)
	Denominator for income/(loss) per share - basic	251,528			249,969			238,851
	Incremental shares issuable from assumed conversion of:	1,917			—			—
	Stock options and unvested resticted stock
	Denominator for income/(loss) per share - diluted	253,445			249,969			238,851
	Income/(loss) per weighted average common share - basic:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.6		$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—			0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.6		$	0.16		$	0.85
	Income/(loss) per weighted average common share - diluted:
	Income/(loss) from continuing operations attributable to common stockholders	$	0.59		$	(0.01	)	$	(0.22	)
	Income/(loss) from discontinued operations attributable to common stockholders	—			0.17			1.07
	Net income/(loss) attributable to common stockholders	$	0.59		$	0.16		$	0.85
United Dominion Reality L P [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table sets forth the computation of basic and diluted income/(loss) per OP Unit for the periods presented (dollars in thousands, except per OP Unit data):
		Year Ended December 31,
		2014			2013			2012
	Numerator for income/(loss) per OP Unit — basic and diluted:
	Income/(loss) from continuing operations	$	33,544		$	32,766		$	(13,309	)
	Gain/(loss) on sale of real estate owned	63,635			—			—
	(Income)/loss from continuing operations attributable to noncontrolling interests	(952		)	(4,114		)	(100		)
	Income/(loss) from continuing operations attributable to OP unitholders	$	96,227		$	28,652		$	(13,409	)
	Income/(loss) from discontinued operations	$	—		$	45,176		$	57,643
	(Income)/loss from discontinued operations attributable to noncontrolling interests	—			(452		)	(252		)
	Income/(loss) from discontinued operations attributable to OP unitholders	$	—		$	44,724		$	57,391
	Net income/(loss)	$	97,179		$	77,942		$	44,334
	Net (income)/loss attributable to noncontrolling interests	(952		)	(4,566		)	(352		)
	Net income/(loss) attributable to OP unitholders	$	96,227		$	73,376		$	43,982
	Denominator for income/(loss) per OP Unit — basic and diluted:
	Weighted average OP Units outstanding — basic and diluted	183,279			184,196			184,281
	Income/(loss) per weighted average OP Unit — basic and diluted:
	Income/(loss) from continuing operations attributable to OP unitholders	$	0.53		$	0.16		$	(0.07	)
	Income/(loss) from discontinued operations attributable to OP unitholders	—			0.24			0.31
	Net income/(loss) attributable to OP unitholders	$	0.53		$	0.4		$	0.24

Consolidation_and_Basis_of_Pre2

Consolidation and Basis of Presentation (Details)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Apartment_Homes
	Markets
Consolidation And Basis Of Presentation (Textual) [Abstract]
Number of markets operating within	20
Number of apartments owned	39,851
Joint venture, number of homes in communities	10,055
Operating Partnership outstanding units	183,278,698	183,278,698
OP units outstanding related to limited partner	183,278,698	183,278,698	184,281,254	184,281,254
General Partner [Member]
Consolidation And Basis Of Presentation (Textual) [Abstract]
OP units outstanding related to limited partner	174,113,225	173,959,774
Percentage of units outstanding owned by limited partners		94.90%
Limited Partner [Member]
Consolidation And Basis Of Presentation (Textual) [Abstract]
Percentage of units outstanding owned by limited partners	95.00%
Non-affiliated Partners
Consolidation And Basis Of Presentation (Textual) [Abstract]
OP units outstanding related to limited partner	9,165,473	9,318,924
Percentage of units outstanding owned by limited partners	5.00%	5.10%

Significant_Accounting_Policie5

Significant Accounting Policies (Details) (USD $)	1 Months Ended	3 Months Ended																12 Months Ended
	Jul. 31, 2014	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	31-May-12
Accounting Policies [Line Items]
Document Period End Date																		31-Dec-14
Significant Accounting Policies (Textual) [Abstract]
Development costs excluding direct costs and capitalized interest																		$8,953,000	$11,100,000	$10,000,000
Interest capitalized during period																		20,200,000	29,400,000	26,400,000
Notes receivable		14,369,000								83,033,000								14,369,000	83,033,000
Note maturity public capital threshold																		5,000,000
Note receivable interest income										3,400,000									4,100,000	2,700,000
Deferred tax asset		6,976,000								32,273,000								6,976,000	32,273,000	24,175,000
Net of a valuation allowance		0								1,310,000								0	1,310,000	1,390,000
Valuation Allowance, Deferred Tax Asset, Change in Amount																		400,000		44,400,000
Income tax benefit resulting in change in valuation allowance																				-21,500,000
Numerator for earnings per share b basic and diluted:
Net (loss)/income attributable to common stockholders		64,486,000		39,618,000		29,076,000		17,430,000		35,769,000		2,257,000		4,261,000		-1,199,000		150,610,000	41,088,000	203,376,000
Weighted average common shares outstanding																		252,707,000	250,684,000	239,482,000
Weighted Average Number of Shares Outstanding, Basic and Diluted																		251,528,000	249,969,000	238,851,000
Net income/(loss) attributable to common stockholders b basic and diluted (in dollars per share)		$0.25	[1]	$0.16	[1]	$0.12	[1]	$0.07	[1]	$0.14	[1]	$0.01	[1]	$0.02	[1]	$0	[1]
Advertising expense																		6,000,000	5,700,000	6,200,000
(Decrease)/increase in net income (loss)																		0	0	-2,791,000
Income Tax Expense (benefits), Discontinued Operations, Change in Valuation Allowance																				22,900,000
Income Tax Expense (Benefit)																		25,994,000	-8,281,000	-21,076,000
Income Tax Examination, Likelihood of Unfavorable Settlement		not (greater than 50 percent probability)
Income Tax Examination, Penalties and Interest Accrued		0																0
Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company																				0.1
Interest Income, Related Party																		0	765,000	281,000
(Issuance)/repayment of notes receivable																		68,664,000	-19,027,000	-63,998,000
Gain (Loss) on Sale of Notes Receivable	8,400,000
6.75% Series G Cumulative Redeemable Preferred Stock
Numerator for earnings per share b basic and diluted:
Preferred stock, dividend rate																				6.75%
Preferred stock, shares redeemed																				3,264,362
Preferred stock, redemption price per share																					$25
Preferred stock, redemption amount																					82,100,000
Note Due March 2014 Related Party [Domain]
Significant Accounting Policies (Textual) [Abstract]
Basis spread on variable rate		35000.00%																35000.00%
Note due October 2014 - related party
Significant Accounting Policies (Textual) [Abstract]
Notes receivable		0								40,800,000								0	40,800,000
Note due February 2017
Significant Accounting Policies (Textual) [Abstract]
Notes receivable		11,869,000								14,580,000								11,869,000	14,580,000
Note Receivable Interest Rate		10.00%																10.00%
Increase (Decrease) in Notes Receivables																		1,200,000
Note maturity public capital threshold																		5,000,000
Proceeds from Collection of Notes Receivable																		3,900,000
Note due June 2022 (net of discount of $283)
Significant Accounting Policies (Textual) [Abstract]
Notes receivable		0								26,253,000								0	26,253,000	26,500,000
Note Receivable Interest Rate																				7.00%
Note receivable, unamortized discount		0								0								0	0
Discount rate on note receivable																				7.25%
Numerator for earnings per share b basic and diluted:
(Issuance)/repayment of notes receivable	36,000,000
Other
Significant Accounting Policies (Textual) [Abstract]
Notes receivable		2,500,000								1,400,000								2,500,000	1,400,000
Note Receivable Interest Rate		8.00%																8.00%
Increase (Decrease) in Notes Receivables																		1,100,000
OP Units
Numerator for earnings per share b basic and diluted:
Antidilutive securities																		9,247,049	9,337,464	9,411,000
Preferred Stock
Numerator for earnings per share b basic and diluted:
Antidilutive securities																		3,035,548	3,035,548	3,036,000
Stock options and unvested restricted stock
Numerator for earnings per share b basic and diluted:
Antidilutive securities																		1,916,979	1,583,537	1,361,398
Minimum | Buildings
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		35 years
Minimum | Building improvements
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		10 years
Minimum | Furniture, fixtures, equipment, and other assets
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		3 years
Maximum | Buildings
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		55 years
Maximum | Building improvements
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		35 years
Maximum | Furniture, fixtures, equipment, and other assets
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		10 years
RedeemableNoncontrollingInterest [Member]
Accounting Policies [Line Items]
Other Comprehensive (Income) Loss, Net of Tax, Portion Attributable to Noncontrolling Interest																		-133,000	250,000	80,000
Continuing Operations [Member]
Numerator for earnings per share b basic and diluted:
Income Tax Expense (Benefit)																		-15,098,000	-7,299,000	-30,282,000
Discontinued Operations [Member]
Numerator for earnings per share b basic and diluted:
Income Tax Expense (Benefit)																		5,000	-982,000	9,641,000
Lodge at Stoughton
Significant Accounting Policies (Textual) [Abstract]
Equity Method Investment, Ownership Percentage										95.00%									95.00%
Joint Venture Number of Operating Communities Owned		1																1
Number of extension options on loan																		2
Extension period of option on loan																		3 months
United Dominion Reality L P [Member]
Accounting Policies [Line Items]
Document Period End Date																		31-Dec-14
Deferred Tax Liabilities, Net		0																0
Significant Accounting Policies (Textual) [Abstract]
Development costs excluding direct costs and capitalized interest																		2,010,000	2,500,000	2,100,000
Interest capitalized during period																		2,900,000	5,900,000	3,700,000
Numerator for earnings per share b basic and diluted:
Advertising expense																		2,500,000	2,500,000	2,400,000
Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company																		0.1
United Dominion Reality L P [Member] | Minimum | Buildings
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		35 years
United Dominion Reality L P [Member] | Minimum | Building improvements
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		10 years
United Dominion Reality L P [Member] | Minimum | Furniture, fixtures, equipment, and other assets
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		3 years
United Dominion Reality L P [Member] | Maximum | Buildings
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		55 years
United Dominion Reality L P [Member] | Maximum | Building improvements
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		35 years
United Dominion Reality L P [Member] | Maximum | Furniture, fixtures, equipment, and other assets
Significant Accounting Policies (Textual) [Abstract]
Estimated useful lives																		10 years
Preferred Stock
Numerator for earnings per share b basic and diluted:
Preferred stock, shares redeemed																		0		3,264,362
Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member]
Significant Accounting Policies (Textual) [Abstract]
Notes receivable		$14,369,000								$83,033,000								$14,369,000	$83,033,000
[1]	Quarterly income/(loss) per share amounts may not total to the annual amounts.

Real_Estate_Owned_Details

Real Estate Owned (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Document Period End Date	31-Dec-14
Summary of carrying amounts for real estate owned (at cost)
Land and Land Improvements	$1,980,221	$1,847,127
Investment Building and Building Improvements, and Furniture, Fixtures and Equipment	6,225,406	5,876,717
Under development:
Real estate under development (net of accumulated depreciation of $0 and $1,411, respectively)	177,632	466,002
Sold or held for sale:
Real estate owned	8,383,259	8,207,977
Accumulated depreciation	-2,434,772	-2,208,794	-1,924,682	-1,831,727
Total real estate owned, net of accumulated depreciation	5,948,487	5,999,183
Land
Under development:
Real estate under development (net of accumulated depreciation of $0 and $1,411, respectively)	24,584	110,769
Sold or held for sale:
Sold or held for sale	0	10,751
Construction in progress
Under development:
Real estate under development (net of accumulated depreciation of $0 and $1,411, respectively)	153,048	356,644
Building and improvements
Sold or held for sale:
Sold or held for sale	$0	$5,969

Real_Estate_Owned_Details_Text

Real Estate Owned (Details Textual) (USD $)	3 Months Ended	12 Months Ended			9 Months Ended	2 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Feb. 19, 2015	Jun. 30, 2013
		Apartment_Homes
		Communities
Real Estate Properties [Line Items]
Document Period End Date		31-Dec-14
Real Estate Owned (Textual) [Abstract]
Number of apartment homes owned and consolidated by the Company		39,851
Communities Sold		9
Apartment Homes Sold		2,500	914	6,507
Deferred Gain on Sale of Property		$24,683,000	$25,400,000
Joint venture, number of homes in communities		10,055
Property, Plant and Equipment, Additions			129,400,000
Number of apartment homes acquired	358
Acquisition-related costs		400,000	100,000	2,300,000
Number of Real Estate Properties		2
Number of States in which Entity Operates		10
Number of Communities Acquired	2
Other Cost and Expense, Operating		8,271,000	7,136,000	5,718,000
Proceeds from Sale of Property, Plant, and Equipment		328,400,000	81,100,000	609,400,000
Payments for (Proceeds from) Investments		-383,886,000	-250,043,000	-593,167,000
Gain (Loss) on Disposition of Property Plant Equipment		138,600,000
Noncash or Part Noncash Acquisition, Debt Assumed		0	63,595,000	34,412,000
Consolidated Joint Venture One [Member]
Real Estate Owned (Textual) [Abstract]
Property, Plant and Equipment, Additions			129,400,000
Number of Communities Acquired			2
Unconsolidated Joint Venture Vitruvian Park [Member]
Real Estate Owned (Textual) [Abstract]
Equity method investment, ownership percent			50.00%				50.00%
Communities Sold			5
Land Sold, Acres			28.4
Deferred Gain on Sale of Property			436,000
Proceeds from Real Estate and Real Estate Joint Ventures			141,300,000
Transaction costs of selling interest in partnerships			936,000
Texas JV
Real Estate Owned (Textual) [Abstract]
Deferred Gain on Sale of Property		23,900,000	24,000,000
Joint Venture Number of Operating Communities Owned				2
Payments to acquire businesses and interest in affiliates				11,700,000
Unconsolidated Joint Venture 399 Fremont [Member]
Real Estate Owned (Textual) [Abstract]
Equity method investment, ownership percent			49.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			49.00%
Proceeds from Issuance or Sale of Equity			29,900,000
Purchase Obligation			318,000,000
Operating Community [Member]
Real Estate Owned (Textual) [Abstract]
Communities Sold		1
Gain (Loss) on Disposition of Property Plant Equipment		142,500,000
Operating Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Real Estate Owned (Textual) [Abstract]
Equity method investment, ownership percent		50.00%	50.00%
Number of Units in Real Estate Property		1,394
Number of Real Estate Properties		3	2
Operating Community [Member] | Texas JV
Real Estate Owned (Textual) [Abstract]
Equity method investment, ownership percent		20.00%	20.00%
Number of Units in Real Estate Property		3,359
Number of Real Estate Properties		8		10
Development Community [Member] | Unconsolidated Joint Venture 399 Fremont [Member]
Real Estate Owned (Textual) [Abstract]
Number of Units in Real Estate Property			447
Land
Real Estate Owned (Textual) [Abstract]
Gain (Loss) on Disposition of Property Plant Equipment		1,100,000
Land | Unconsolidated Joint Venture Vitruvian Park [Member]
Real Estate Owned (Textual) [Abstract]
Number of Real Estate Properties		6
New York Properties [Member]
Real Estate Properties [Line Items]
Impairment of Long-Lived Assets Held-for-use			0	9,000,000
Real Estate Owned (Textual) [Abstract]
Number of Communities Owned				3
Number of Apartments Owned				1,706
Other Cost and Expense, Operating				10,400,000
Hurricane Sandy [Member]
Real Estate Owned (Textual) [Abstract]
Total Estimated Insurance Recovery				14,500,000
Lightbox [Member]
Real Estate Owned (Textual) [Abstract]
Property, Plant and Equipment, Additions					45,500,000
Waterscape [Member]
Real Estate Owned (Textual) [Abstract]
Property, Plant and Equipment, Additions					75,200,000
Graybar [Member]
Real Estate Owned (Textual) [Abstract]
Property, Plant and Equipment, Additions					32,200,000
Operating Community [Member]
Real Estate Owned (Textual) [Abstract]
Payments for (Proceeds from) Investments		-324,400,000
Land
Real Estate Owned (Textual) [Abstract]
Property, Plant and Equipment, Additions					77,800,000
Development Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Real Estate Owned (Textual) [Abstract]
Communities Sold			1
Apartment Homes Sold			391
13th & Market [Member]
Real Estate Owned (Textual) [Abstract]
Equity method investment, ownership percent		49.00%
Proceeds from Sale of Property, Plant, and Equipment		54,200,000
Gain (Loss) on Disposition of Property Plant Equipment		7,200,000
3033 Wilshire
Real Estate Owned (Textual) [Abstract]
Equity method investment, ownership percent		50.00%
Proceeds from Sale of Property, Plant, and Equipment		8,300,000
Gain (Loss) on Disposition of Property Plant Equipment		2,200,000
Unconsolidated Joint Venture 399 Fremont [Member]
Real Estate Owned (Textual) [Abstract]
Proceeds from Sale of Property, Plant, and Equipment			29,900,000
Operating Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Real Estate Owned (Textual) [Abstract]
Communities Sold			2
Apartment Homes Sold			739
Subsequent Event [Member]
Real Estate Owned (Textual) [Abstract]
Square Footage						120,000
Subsequent Event [Member] | Texas JV
Real Estate Owned (Textual) [Abstract]
Communities Sold						8
Proceeds from Sale of Property, Plant, and Equipment						43,500,000
Gain (Loss) on Disposition of Property Plant Equipment						59,100,000
Subsequent Event [Member] | Office Building [Member]
Real Estate Owned (Textual) [Abstract]
Property, Plant and Equipment, Additions						$24,000,000
Subsequent Event [Member] | UDR, Inc.
Real Estate Owned (Textual) [Abstract]
Square Footage						44,000

Discontinued_Operations_Detail

Discontinued Operations (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
									Communities	Communities	Apartment_Homes
											Communities
Document Period End Date									31-Dec-14
Gain (Loss) on Disposition of Property Plant Equipment									$138,600,000
Discontinued Operations (Textual) [Abstract]
Discontinued operations, number of communities sold									1	2	21
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax									75,000	41,919,000	260,404,000
Proceeds from Sale of Property, Plant, and Equipment									328,400,000	81,100,000	609,400,000
Number of communities sold									9
Number of apartment homes sold									2,500	914	6,507
Impairment loss, net of tax									0	1,470,000	0
Summary of income from discontinued operations
Rental income									147,000	9,152,000	39,543,000
Rental expenses									225,000	3,511,000	14,106,000
Property management fee									4,000	252,000	1,087,000
Real estate depreciation									0	1,958,000	8,475,000
Interest									21,000	-62,000	821,000
Income before net gain on the sale of property									-103,000	3,493,000	15,054,000
Impairment of Long-Lived Assets to be Disposed of									0	-2,355,000	0
Income tax expense									38,000	885,000	-8,850,000
Income/(loss) from discontinued operations, net of tax	0	79,000	18,000	-87,000	41,376,000	884,000	829,000	853,000	10,000	43,942,000	266,608,000
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent									10,000	42,364,000	256,533,000
Land
Gain (Loss) on Disposition of Property Plant Equipment									1,100,000
Operating Community [Member]
Gain (Loss) on Disposition of Property Plant Equipment									$142,500,000
Discontinued Operations (Textual) [Abstract]
Number of communities sold									1

Joint_Ventures_Details

Joint Ventures (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014	Sep. 30, 2014	Jun. 30, 2013
				Communities	Land_Parcels
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	$718,226,000	$507,655,000
Deferred Gain on Sale of Property	24,683,000	25,400,000
MetLife I
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	13,306,000	47,497,000
MetLife I | Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	4			6
Number of Units in Real Estate Property	0
Investment in and advances to unconsolidated joint ventures, net	13,306,000	47,497,000
Equity method investment, ownership percent	15.70%	4.50%
MetLife I | Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3
Equity method investment, ownership percent	5.00%
MetLife II
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	431,277,000	327,926,000
MetLife II | Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	21
Number of Units in Real Estate Property	4,642
Investment in and advances to unconsolidated joint ventures, net	431,277,000	327,926,000
Equity method investment, ownership percent	50.00%	50.00%
MetLife II | Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties					2
Equity method investment, ownership percent					50.10%
Unconsolidated Joint Venture Other MetLife [Member] | Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	1
Number of Units in Real Estate Property	1,282
Investment in and advances to unconsolidated joint ventures, net	134,939,000	36,313,000
Equity method investment, ownership percent	50.60%	35.80%
Unconsolidated Joint Venture Other MetLife [Member] | Development Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3
Unconsolidated Joint Venture Other MetLife [Member] | Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	2
Unconsolidated Joint Venture Vitruvian Park [Member]
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	80,302,000	79,318,000
Equity method investment, ownership percent		50.00%				50.00%
Deferred Gain on Sale of Property		436,000
Unconsolidated Joint Venture Vitruvian Park [Member] | Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3	2
Number of Units in Real Estate Property	1,394
Investment in and advances to unconsolidated joint ventures, net	80,302,000	79,318,000
Equity method investment, ownership percent	50.00%	50.00%
Unconsolidated Joint Venture Vitruvian Park [Member] | Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	6
Unconsolidated Joint Venture 399 Fremont [Member]
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net		31,100,000
Equity method investment, ownership percent		49.00%
Unconsolidated Joint Venture 399 Fremont [Member] | Development Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Units in Real Estate Property		447
Lodge at Stoughton
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percent		95.00%
KFH
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	21,596,000	25,919,000
Equity method investment, ownership percent	30.00%
KFH | Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3
Number of Units in Real Estate Property	660
Investment in and advances to unconsolidated joint ventures, net	21,596,000	25,919,000
Equity method investment, ownership percent	30.00%	30.00%
Texas JV
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	-25,901,000	-23,591,000
Deferred Gain on Sale of Property	23,900,000	24,000,000
Texas JV | Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	8		10
Number of Units in Real Estate Property	3,359
Investment in and advances to unconsolidated joint ventures, net	-25,901,000	-23,591,000
Equity method investment, ownership percent	20.00%	20.00%
399 Fremont
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net			55,500,000
Unconsolidated Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	655,519,000	493,382,000
Participating Loan Investment Steele Creek Denver Colorado [Member]
Schedule of Equity Method Investments [Line Items]
Income from Participating Loan	156,000
Participating Loan Investment Steele Creek Denver Colorado [Member] | Development Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Units in Real Estate Property	218
Investment in and advances to unconsolidated joint ventures, net	62,707,000	14,273,000
Participating Loan, Interest Rate, Stated Percentage	6.50%
Participating Loan Years to Maturity	2 years 10 months 0 days
Income from Participating Loan	$2,350,000	$156,000	$0

Joint_Ventures_Details_1

Joint Ventures (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial information relating to unconsolidated joint ventures operations
Revenues	$193,453	$142,842	$109,412
Real estate depreciation and amortization	69,399	51,830	51,120
Net loss	-42,667	-36,075	-3,957
UDR recorded loss from unconsolidated entities	-7,006	-415	-8,579
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	2,941,803	2,165,667
Total assets	3,219,250	3,198,204
Amount due to UDR	2,997	9,703
Third party debt	1,504,477	1,164,007
Total liabilities	1,781,515	1,776,709
Total equity	1,437,735	1,421,495
Investment in and advances to unconsolidated joint ventures, net	718,226	507,655
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	229,706	577,203
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	216,196	985,408
Property operating expenses	72,099	49,390	34,188
Operating income/(loss)	51,955	41,622	24,104
Interest expense	-58,591	-45,726	-35,621
Other income/(expense)	0	1	-9
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	-36,031	-31,972	7,569
Cash and cash equivalents	32,544	22,546
Other assets	28,707	24,583
Accounts payable and accrued liabilities	44,335	25,796
MetLife I
Financial information relating to unconsolidated joint ventures operations
Revenues	727	691	632
Real estate depreciation and amortization	2,130	115	124
Net loss	-33,823	-22,433	8,865
UDR recorded loss from unconsolidated entities	-2,955	-4,675	-1,750
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	89,482	90,971
Total assets	93,297	849,485
Amount due to UDR	107	4,520
Third party debt	0	0
Total liabilities	5,966	351,419
Total equity	87,331	498,066
Investment in and advances to unconsolidated joint ventures, net	13,306	47,497
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	5,110	346,810
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	1,978	753,427
Property operating expenses	618	621	252
Operating income/(loss)	-2,021	-45	256
Interest expense	0	0	0
Other income/(expense)	0	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	-31,802	-22,388	8,609
Cash and cash equivalents	1,983	305
Other assets	-146	4,782
Accounts payable and accrued liabilities	749	89
MetLife II
Financial information relating to unconsolidated joint ventures operations
Revenues	152,047	109,926	87,386
Real estate depreciation and amortization	41,504	30,122	32,553
Net loss	9,900	8,941	-83
UDR recorded loss from unconsolidated entities	2,814	4,471	15
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	1,986,237	1,476,588
Total assets	2,021,071	1,509,708
Amount due to UDR	-444	2,275
Third party debt	1,147,109	877,799
Total liabilities	1,164,238	894,582
Total equity	856,833	615,126
Investment in and advances to unconsolidated joint ventures, net	431,277	327,926
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	0	0
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	0	0
Property operating expenses	52,150	33,809	25,737
Operating income/(loss)	58,393	45,995	29,096
Interest expense	-48,493	-37,055	-29,170
Other income/(expense)	0	1	-9
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	0	0	0
Cash and cash equivalents	15,245	16,454
Other assets	19,589	16,666
Accounts payable and accrued liabilities	17,573	14,508
Unconsolidated Joint Venture Vitruvian Park [Member]
Financial information relating to unconsolidated joint ventures operations
Revenues	19,376	7,680	0
Real estate depreciation and amortization	7,380	3,830	0
Net loss	-2,846	-2,669	0
UDR recorded loss from unconsolidated entities	-4,068	-2,851	0
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	278,600	283,878
Total assets	289,103	288,954
Amount due to UDR	1,960	1,352
Third party debt	123,649	120,999
Total liabilities	132,375	129,503
Total equity	156,728	159,451
Investment in and advances to unconsolidated joint ventures, net	80,302	79,318
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	0	0
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	0	0
Property operating expenses	10,711	4,633	0
Operating income/(loss)	1,285	-783	0
Interest expense	-4,131	-1,886	0
Other income/(expense)	0	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	0	0	0
Cash and cash equivalents	6,570	3,498
Other assets	3,933	1,578
Accounts payable and accrued liabilities	6,766	7,152
Texas JV
Financial information relating to unconsolidated joint ventures operations
Revenues	0	0	0
Real estate depreciation and amortization	0	0	0
Net loss	-4,229	-9,584	-1,040
UDR recorded loss from unconsolidated entities	-772	-1,218	-2,399
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	0	0
Total assets	214,218	231,981
Amount due to UDR	0	0
Third party debt	0	0
Total liabilities	224,596	230,393
Total equity	-10,378	1,588
Investment in and advances to unconsolidated joint ventures, net	-25,901	-23,591
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	224,596	230,393
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	214,218	231,981
Property operating expenses	0	0	0
Operating income/(loss)	0	0	0
Interest expense	0	0	0
Other income/(expense)	0	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	-4,229	-9,584	-1,040
Cash and cash equivalents	0	0
Other assets	0	0
Accounts payable and accrued liabilities	0	0
KFH
Financial information relating to unconsolidated joint ventures operations
Revenues	19,724	19,221	18,670
Real estate depreciation and amortization	14,426	14,199	16,546
Net loss	-8,073	-7,885	-10,597
UDR recorded loss from unconsolidated entities	-2,601	-2,366	-3,221
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	235,623	249,097
Total assets	239,258	252,860
Amount due to UDR	531	420
Third party debt	165,209	165,209
Total liabilities	167,136	166,863
Total equity	72,122	85,997
Investment in and advances to unconsolidated joint ventures, net	21,596	25,919
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	0	0
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	0	0
Property operating expenses	7,498	7,035	6,831
Operating income/(loss)	-2,200	-2,013	-4,707
Interest expense	-5,873	-5,872	-5,890
Other income/(expense)	0	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	0	0	0
Cash and cash equivalents	2,507	2,289
Other assets	1,128	1,474
Accounts payable and accrued liabilities	1,396	1,234
Unconsolidated Other Joint Ventures [Domain]
Financial information relating to unconsolidated joint ventures operations
Revenues	1,579	5,324	2,724
Real estate depreciation and amortization	3,959	3,564	1,897
Net loss	-3,596	-2,445	-1,102
UDR recorded loss from unconsolidated entities	576	6,224	-1,224
Combined summary of balance sheets relating to unconsolidated joint ventures
Real estate, net	351,861	65,133
Total assets	362,303	65,216
Amount due to UDR	843	1,136
Third party debt	68,510	0
Total liabilities	87,204	3,949
Total equity	275,099	61,267
Investment in and advances to unconsolidated joint ventures, net	197,646	50,586
Equity Method of Investment Summarized Financial Information, Liabilities Sold or Held For Sale	0	0
Equity Method of Investment Summarized Financial Information, Assets Sold or Held For Sale	0	0
Property operating expenses	1,122	3,292	1,368
Operating income/(loss)	-3,502	-1,532	-541
Interest expense	-94	-913	-561
Other income/(expense)	0	0	0
Equity Method Investment, Summarized Financial Information, Gain (Loss) on Sale of Real Estate	0
Income/(loss) from discontinued operations	0	0	0
Cash and cash equivalents	6,239	0
Other assets	4,203	83
Accounts payable and accrued liabilities	17,851	2,813
Unconsolidated Joint Ventures [Member]
Combined summary of balance sheets relating to unconsolidated joint ventures
Investment in and advances to unconsolidated joint ventures, net	$655,519	$493,382

Joint_Ventures_Details_Textual

Joint Ventures (Details Textual) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended			9 Months Ended	1 Months Ended	3 Months Ended	2 Months Ended
	Jun. 30, 2013	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Jul. 31, 2014	Sep. 30, 2014	Feb. 19, 2015	Jan. 31, 2014	Jan. 31, 2012	Mar. 31, 2014
		Communities	Communities									Communities
		Apartment_Homes	Apartment_Homes
Joint Ventures
Real Estate Investment Property, Net		$5,770,855,000	$5,770,855,000	$5,523,029,000
Debt associated with Real estate acquired				63,600,000
Joint venture, number of homes in communities		10,055	10,055
Ownership interest in joint venture purchased				100.00%
Initial investment in equity method investment				80,200,000
Property, Plant and Equipment, Additions				129,400,000
Unamortized discount		6,700,000	6,700,000	11,800,000
First installment of payable incurred in partial consideration for acquisition of ownership interest in joint venture		520,934,000	520,934,000
Second installment of payable incurred in partial consideration for acquisition of ownership interest in joint venture		248,881,000	248,881,000
Interest expense incurred during period			130,454,000	126,083,000	138,792,000
Company's equity investment in joint venture		718,226,000	718,226,000	507,655,000
Ownership interest in underlying assets exchanged	10.00%
Cash paid in equity method investment exchange	15,600,000
Weighted Average Interest Rate		3.94%
Payments to acquire equity method investments			222,930,000	43,291,000	283,369,000
Document Period End Date			31-Dec-14
Deferred gains on the sale of depreciable property		24,683,000	24,683,000	25,400,000
Communities Sold			9
Proceeds from Sale of Property, Plant, and Equipment			328,400,000	81,100,000	609,400,000
Gain (Loss) on Disposition of Property Plant Equipment			138,600,000
Management fees for our involvement in the joint ventures			11,300,000	11,200,000	11,800,000
Deposits										4,000,000
Real Estate Owned Gross		8,383,259,000	8,383,259,000	8,207,977,000
Secured debt		1,361,529,000	1,361,529,000	1,442,077,000
SEC Schedule III, Real Estate, Cost of Real Estate Sold	140,000,000		269,681,000	70,687,000	559,154,000
Percentage of real estate retained in sale of real estate owned				50.00%
Number of Real Estate Properties		139	139
13th & Market and DCP [Member]
Joint Ventures
Property, Plant and Equipment, Additions						24,700,000
Wilshire Crescent Heights [Member]
Joint Ventures
Property, Plant and Equipment, Additions						15,300,000
Land
Joint Ventures
Property, Plant and Equipment, Additions						77,800,000
Denver and San Diego Operating Communities [Member]
Joint Ventures
Equity method investment, ownership percent				50.00%
Number of operating communities in equity method investment exchange	2
Ownership interest acquired in exchange	35.00%
MetLife Swap [Member]
Joint Ventures
Equity method investment, ownership percent				12.00%		50.00%		50.00%
Cash paid in equity method investment exchange							21,500,000	82,500,000
Communities Sold						2
Proceeds from Sale of Property, Plant, and Equipment						3,000,000
13th & Market [Member]
Joint Ventures
Deposits										2,000,000
Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Equity method investment, ownership percent	50.00%			50.00%
Company's equity investment in joint venture		80,302,000	80,302,000	79,318,000
Deferred gains on the sale of depreciable property				436,000
Communities Sold				5
Proceeds from Real Estate and Real Estate Joint Ventures				141,300,000
Stated interest rate				4.00%
MetLife I
Joint Ventures
Company's equity investment in joint venture		13,306,000	13,306,000	47,497,000
MetLife II
Joint Ventures
Company's equity investment in joint venture		431,277,000	431,277,000	327,926,000
399 Fremont
Joint Ventures
Initial investment in equity method investment											37,300,000
Ownership percentage				7.50%	7.50%
Company's equity investment in joint venture					55,500,000
Non-controlling interest held in joint venture											92.50%
399 Fremont | 1st payment
Joint Ventures
Payments for interest in joint venture					13,500,000
399 Fremont | 2nd payment
Joint Ventures
Payments for interest in joint venture				4,700,000
Lodge at Stoughton
Joint Ventures
Number of operating communities in joint venture		1	1
Equity method investment, ownership percent				95.00%
Bridge Loan		40,800,000	40,800,000
Number of extension options on loan			2
Extension period of option on loan			3 months
KFH
Joint Ventures
Equity method investment, ownership percent		30.00%	30.00%
Company's equity investment in joint venture		21,596,000	21,596,000	25,919,000
Joint venture investment in multifamily properties		450,000,000	450,000,000
Total equity contribution by partners when fully invested		180,000,000	180,000,000
UDR's equity investment in joint venture when fully invested		54,000,000	54,000,000
Texas JV
Joint Ventures
Ownership interest in joint venture purchased					80.00%
Number of operating communities in joint venture					2
Company's equity investment in joint venture		-25,901,000	-25,901,000	-23,591,000
Payments to acquire businesses and interest in affiliates					11,700,000
Deferred gains on the sale of depreciable property		23,900,000	23,900,000	24,000,000
Texas JV | Subsequent Event [Member]
Joint Ventures
Communities Sold									8
Proceeds from Sale of Property, Plant, and Equipment									43,500,000
Fee Income from the Sale of Real Estate									9,600,000
Gain (Loss) on Disposition of Property Plant Equipment									59,100,000
13th & Market
Joint Ventures
Ownership percentage		0.00%	0.00%	5.00%
Non-controlling interest held in joint venture				95.00%
Orange County, CA
Joint Ventures
Property, Plant and Equipment, Additions				129,400,000
Unconsolidated Joint Venture 399 Fremont [Member]
Joint Ventures
Ownership percentage				49.00%
Purchase Obligation				318,000,000
Proceeds from Issuance or Sale of Equity				29,900,000
Equity method investment, ownership percent				49.00%
Company's equity investment in joint venture				31,100,000
Participating Loan Investment Steele Creek Denver Colorado [Member]
Joint Ventures
Maximum Percentage to Finance		85.00%	85.00%
Line of Credit Facility, Maximum Borrowing Capacity		92,000,000	92,000,000
Weighted average interest rate at the end of the period		6.50%	6.50%
Participating Interest in Investment		50.00%	50.00%
Income from Participating Loan			156,000
Fully Entitled Land [Member] | MetLife I
Joint Ventures
Equity method investment, ownership percent		50.00%	50.00%
Number of Real Estate Properties		1	1
Land
Joint Ventures
Gain (Loss) on Disposition of Property Plant Equipment			1,100,000
Land | Unconsolidated Joint Venture Other MetLife [Member]
Joint Ventures
Number of Real Estate Properties		2	2
Land | Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Number of Real Estate Properties		6	6
Land | MetLife I
Schedule of Equity Method Investments [Line Items]
Number of apartments of development community		0	0
Joint Ventures
Equity method investment, ownership percent		5.00%	5.00%
Number of Real Estate Properties		3	3
Land | MetLife II
Joint Ventures
Equity method investment, ownership percent						50.10%		50.10%
Number of Real Estate Properties						2		2
Land | Noncontrolling Interest
Joint Ventures
Equity method investment, ownership percent						49.90%		49.90%
Land | Wilshire at LaJolla [Member]
Joint Ventures
Equity method investment, ownership percent						50.10%		50.10%
Land | Wilshire Crescent Heights [Member]
Joint Ventures
Equity method investment, ownership percent						50.00%		50.00%
Number of Real Estate Properties		1	1
Operating Community [Member]
Joint Ventures
Number of operating communities in equity method investment exchange	4
Communities Sold			1
Gain (Loss) on Disposition of Property Plant Equipment			142,500,000
Operating Community [Member] | Unconsolidated Joint Venture Other MetLife [Member]
Joint Ventures
Number of Units in Real Estate Property		1,282	1,282
Equity method investment, ownership percent		50.60%	50.60%	35.80%
Company's equity investment in joint venture		134,939,000	134,939,000	36,313,000
Number of Real Estate Properties		1	1
Operating Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Number of Units in Real Estate Property		1,394	1,394
Equity method investment, ownership percent		50.00%	50.00%	50.00%
Company's equity investment in joint venture		80,302,000	80,302,000	79,318,000
Number of Real Estate Properties		3	3	2
Operating Community [Member] | MetLife I
Joint Ventures
Number of Units in Real Estate Property		0	0
Equity method investment, ownership percent		15.70%	15.70%	4.50%
Company's equity investment in joint venture		13,306,000	13,306,000	47,497,000
Number of Real Estate Properties		4	4									6
Operating Community [Member] | MetLife II
Joint Ventures
Number of Units in Real Estate Property		4,642	4,642
Equity method investment, ownership percent		50.00%	50.00%	50.00%
Company's equity investment in joint venture		431,277,000	431,277,000	327,926,000
Number of Real Estate Properties		21	21
Operating Community [Member] | KFH
Joint Ventures
Number of Units in Real Estate Property		660	660
Equity method investment, ownership percent		30.00%	30.00%	30.00%
Company's equity investment in joint venture		21,596,000	21,596,000	25,919,000
Number of Real Estate Properties		3	3
Operating Community [Member] | Texas JV
Joint Ventures
Number of Units in Real Estate Property		3,359	3,359
Equity method investment, ownership percent		20.00%	20.00%	20.00%
Company's equity investment in joint venture		-25,901,000	-25,901,000	-23,591,000
Number of Real Estate Properties		8	8		10
Development Community [Member] | Unconsolidated Joint Venture Other MetLife [Member]
Joint Ventures
Number of Real Estate Properties		3	3
Development Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Debt Instrument, Description of Variable Rate Basis	175
Number of extension options on loan	2
Extension period of option on loan	1 year
Development Community [Member] | Unconsolidated Joint Venture 399 Fremont [Member]
Joint Ventures
Number of Units in Real Estate Property				447
Development Community [Member] | Participating Loan Investment Steele Creek Denver Colorado [Member]
Joint Ventures
Number of Units in Real Estate Property		218	218
Company's equity investment in joint venture		62,707,000	62,707,000	14,273,000
Income from Participating Loan			2,350,000	156,000	0
Ownership interest of Company in Partnership [Member]
Joint Ventures
Secured debt				118,300,000
Proceeds from Issuance of Other Long-term Debt	58,700,000
Ownership interest of Company in Partnership [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Real Estate Owned Gross				145,000,000
Secured debt				62,800,000
Unconsolidated Joint Venture Vitruvian Park [Member] | Operating Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Debt Instrument, Term				2 years
Unconsolidated Joint Venture Vitruvian Park [Member] | Development Community [Member] | Unconsolidated Joint Venture Vitruvian Park [Member]
Joint Ventures
Debt Instrument, Term				10 years
Participating Loan Investment Steele Creek Denver Colorado [Member]
Joint Ventures
Purchase Obligation		108,000,000	108,000,000
Number of Real Estate Properties		1	1
13th & Market [Member]
Joint Ventures
Equity method investment, ownership percent		49.00%	49.00%
Proceeds from Sale of Property, Plant, and Equipment			54,200,000
Gain (Loss) on Disposition of Property Plant Equipment			7,200,000
3033 Wilshire
Joint Ventures
Equity method investment, ownership percent		50.00%	50.00%
Proceeds from Sale of Property, Plant, and Equipment			8,300,000
Gain (Loss) on Disposition of Property Plant Equipment			$2,200,000

Secured_Debt_and_Unsecured_Deb2

Secured Debt and Unsecured Debt (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Unamortized discount	$6,700	$6,700	$11,800
Weighted Average Interest Rate	3.94%
Weighted Average Years to Maturity		4 years 3 months 18 days
Borrowings outstanding	1,900	1,900	2,200
Total Unsecured Debt	2,221,576	2,221,576	2,081,626
Total Debt	3,583,105	3,583,105	3,523,703
Fixed Rate Debt
Debt Instrument [Line Items]
Principal outstanding	969,296	969,296	1,072,373
Weighted Average Interest Rate	5.26%
Weighted Average Years to Maturity		3 years 0 months 2 days
Number of Communities Encumbered		28
Variable Rate Debt
Debt Instrument [Line Items]
Principal outstanding	392,233	392,233	369,704
Weighted Average Interest Rate	1.44%
Weighted Average Years to Maturity		5 years 8 months 7 days
Number of Communities Encumbered		10
Three point seven percent medium term note due October 2020 [Member]
Debt Instrument [Line Items]
Stated interest rate	3.70%	3.70%
Unamortized discount	46	46	54
Secured Debt
Debt Instrument [Line Items]
Principal outstanding	1,361,529	1,361,529	1,442,077
Weighted Average Interest Rate	4.16%
Weighted Average Years to Maturity		3 years 9 months 18 days
Number of Communities Encumbered		38
Total Debt	1,361,529	1,361,529
Secured Debt | Fixed Rate Debt
Debt Instrument [Line Items]
Total Debt	969,296	969,296
Secured Debt | Variable Rate Debt
Debt Instrument [Line Items]
Total Debt	392,233	392,233
Mortgage notes payable | Fixed Rate Debt
Debt Instrument [Line Items]
Principal outstanding			445,706
Weighted Average Interest Rate	5.46%
Weighted Average Years to Maturity		1 year 7 months 20 days
Number of Communities Encumbered	6
Mortgage notes payable | Variable Rate Debt
Debt Instrument [Line Items]
Principal outstanding			63,595
Weighted Average Interest Rate	1.94%
Weighted Average Years to Maturity		2 years 0 months 25 days
Number of Communities Encumbered	1
Tax-exempt secured notes payable | Variable Rate Debt
Debt Instrument [Line Items]
Principal outstanding			94,700
Weighted Average Interest Rate	0.83%
Weighted Average Years to Maturity		8 years 2 months 8 days
Number of Communities Encumbered	2
Fannie Mae credit facilities | Fixed Rate Debt
Debt Instrument [Line Items]
Principal outstanding			626,667
Debt, Weighted Average Interest Rate	5.12%	5.12%
Weighted Average Years to Maturity		4 years 0 months 10 days
Number of Communities Encumbered	22
Fannie Mae credit facilities | Variable Rate Debt
Debt Instrument [Line Items]
Principal outstanding			211,409
Debt Instrument, Interest Rate at Period End	1.60%	1.60%
Weighted Average Years to Maturity		5 years 2 months 8 days
Number of Communities Encumbered	7
Unsecured Debt
Debt Instrument [Line Items]
Weighted Average Interest Rate	3.81%
Weighted Average Years to Maturity		4 years 7 months 6 days
Total Unsecured Debt	2,221,576	2,221,576	2,081,626
Total Debt	2,221,576	2,221,576
Borrowings outstanding under an unsecured credit facility due October 2015
Debt Instrument [Line Items]
Weighted Average Interest Rate	1.09%
Weighted Average Years to Maturity		2 years 11 months 4 days
Borrowings outstanding	152,500	152,500	0
ThreePointSevenTermNotesDueOctober2020 [Member]
Debt Instrument [Line Items]
Weighted Average Years to Maturity		5 years 9 months
Senior Unsecured Notes	299,954	299,954	299,946
4.63% Medium-Term Notes due January 2022
Debt Instrument [Line Items]
Stated interest rate	4.63%	4.63%	4.63%
Unamortized discount	2,523	2,523	2,882
Weighted Average Interest Rate	4.63%
Weighted Average Years to Maturity		7 years 0 months 10 days
Senior Unsecured Notes	397,477	397,477	397,118
3.75 MTN Due July 2024 [Member]
Debt Instrument [Line Items]
Stated interest rate	3.75%	3.75%
Unamortized discount	990	990
Weighted Average Interest Rate	3.75%
Weighted Average Years to Maturity		9 years 6 months
Senior Unsecured Notes	299,010	299,010	0
1.67% Term Notes due December 2016
Debt Instrument [Line Items]
Stated interest rate	1.31%	1.31%	1.65%
Weighted Average Interest Rate	1.31%
Weighted Average Years to Maturity		3 years 5 months 4 days
Senior Unsecured Notes	35,000	35,000	35,000
2.68% Term Notes due December 2016
Debt Instrument [Line Items]
Stated interest rate	1.53%	1.53%	2.68%
Weighted Average Interest Rate	1.53%
Weighted Average Years to Maturity		3 years 5 months 4 days
Senior Unsecured Notes	100,000	100,000	65,000
5.13% Medium-Term Notes due January 2014
Debt Instrument [Line Items]
Stated interest rate	5.13%	5.13%	5.13%
Weighted Average Interest Rate	0.00%
Weighted Average Years to Maturity		1 day
Senior Unsecured Notes	0	0	184,000
5.50% Medium-Term Notes due April 2014
Debt Instrument [Line Items]
Stated interest rate	5.50%	5.50%	5.50%
Unamortized discount	0	0	20
Weighted Average Interest Rate	0.00%
Weighted Average Years to Maturity		0 days
Senior Unsecured Notes	0	0	128,480
5.25% Medium-Term Notes due January 2015
Debt Instrument [Line Items]
Stated interest rate	5.25%	5.25%	5.25%
Unamortized discount	6	6	134
Weighted Average Interest Rate	5.25%
Weighted Average Years to Maturity		14 days
Senior Unsecured Notes	325,169	325,169	325,041
5.25% Medium-Term Notes due January 2016
Debt Instrument [Line Items]
Stated interest rate	5.25%	5.25%	5.25%
Weighted Average Interest Rate	5.25%
Weighted Average Years to Maturity		1 year 0 months 14 days
Senior Unsecured Notes	83,260	83,260	83,260
2.90% Term Notes due January 2016
Debt Instrument [Line Items]
Stated interest rate	2.17%	2.17%	2.90%
Weighted Average Interest Rate	2.17%
Weighted Average Years to Maturity		3 years 5 months 4 days
Senior Unsecured Notes	215,000	215,000	250,000
8.50% Debentures due September 2024
Debt Instrument [Line Items]
Stated interest rate	8.50%	8.50%	8.50%
Weighted Average Interest Rate	8.50%
Weighted Average Years to Maturity		9 years 8 months 15 days
Senior Unsecured Notes	15,644	15,644	15,644
4.25% Medium-Term Notes due June 2018
Debt Instrument [Line Items]
Stated interest rate	4.25%	4.25%	4.25%
Unamortized discount	1,465	1,465	1,893
Weighted Average Interest Rate	4.25%
Weighted Average Years to Maturity		3 years 5 months 4 days
Senior Unsecured Notes	298,535	298,535	298,107
Other
Debt Instrument [Line Items]
Senior Unsecured Notes	$27	$27	$30

Secured_Debt_and_Unsecured_Deb3

Secured Debt and Unsecured Debt (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2013
Secured credit facilities
Borrowings outstanding	$1,900		$2,200
Fannie Mae
Secured credit facilities
Borrowings outstanding	834,282		838,076
Weighted average daily borrowings during the period ended	835,873	839,597
Maximum daily borrowings during the period ended	$837,564	$841,494
Weighted average interest rate during the period ended	4.10%	4.20%
Weighted average interest rate at the end of the period	4.00%		4.10%

Secured_Debt_and_Unsecured_Deb4

Secured Debt and Unsecured Debt (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Borrowings outstanding at end of period	$1,900	$2,200
Unsecured Commercial Bank Credit Facility
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	900,000	900,000
Borrowings outstanding at end of period	152,500	0
Weighted average daily borrowings during the period ended	291,761	169,844
Maximum daily borrowings during the period ended	$625,000	$372,000
Weighted average interest rate during the period ended	1.20%	1.20%
Interest rate at the end of the period	1.10%	1.30%

Secured_Debt_and_Unsecured_Deb5

Secured Debt and Unsecured Debt (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Aggregate maturities of debt
2013	$520,934
2014	248,881
2015	395,274
2016	874,199
2017	316,438
Thereafter	1,227,379
Total Debt	3,583,105	3,523,703
Secured Debt
Aggregate maturities of debt
2013	196,648
2014	166,504
2015	242,774
2016	225,756
2017	316,438
Thereafter	213,409
Total Debt	1,361,529
Secured Debt | Fixed Rate Debt
Aggregate maturities of debt
2013	196,648
2014	135,167
2015	177,774
2016	120,969
2017	248,738
Thereafter	90,000
Total Debt	969,296
Secured Debt | Variable Rate Debt
Aggregate maturities of debt
2013	0
2014	31,337
2015	65,000
2016	104,787
2017	67,700
Thereafter	123,409
Total Debt	392,233
Unsecured Debt
Aggregate maturities of debt
2013	324,286
2014	82,377
2015	152,500
2016	648,443
2017	0
Thereafter	1,013,970
Total Debt	$2,221,576

Secured_Debt_and_Unsecured_Deb6

Secured Debt and Unsecured Debt (Details Textual) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended			0 Months Ended
	Jun. 30, 2013	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Sep. 26, 2013	Jun. 26, 2014
Secured Debt (Textual) [Abstract]
Secured debt amount which encumbers real estate owned based upon book value		$2,200,000,000		$2,200,000,000
Percentage of secured debt which encumbers real estate owned based upon book value		26.60%		26.60%
Secured debt amount of real estate owned which is unencumbered		6,200,000,000		6,200,000,000
Percentage of secured debt of real estate owned which is unencumbered		73.40%		73.40%
Unamortized fair market adjustment		6,700,000		6,700,000	11,800,000
Weighted Average Interest Rate		3.94%
Long-term Line of Credit		1,900,000		1,900,000	2,200,000
Line of Credit Facility, Interest Rate Description	100
Line of Credit Facility, Commitment Fee Description	15
Fixed Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale		969,296,000		969,296,000	1,072,373,000
Weighted Average Interest Rate		5.26%
Variable Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale		392,233,000		392,233,000	369,704,000
Weighted Average Interest Rate		1.44%
Five Point Two Five Percent, Medium Term Notes, Due January 2015 [Member]
Secured Debt (Textual) [Abstract]
Unamortized fair market adjustment		6,000		6,000	134,000
Weighted Average Interest Rate		5.25%
Fixed interest rate		5.25%		5.25%	5.25%
Senior Notes		325,169,000		325,169,000	325,041,000
3.75 MTN Due July 2024 [Member]
Secured Debt (Textual) [Abstract]
Unamortized fair market adjustment		990,000		990,000
Medium-term Notes							300,000,000
Weighted Average Interest Rate		3.75%
Fixed interest rate		3.75%		3.75%
Percentage of Debt Instrument Price		99.65%		99.65%
Senior Notes		299,010,000		299,010,000	0
1.67% Term Notes due December 2016
Secured Debt (Textual) [Abstract]
Weighted Average Interest Rate		1.31%
Fixed interest rate		1.31%		1.31%	1.65%
Debt Instrument, Maturity Date			1-Jun-18
Senior Notes		35,000,000		35,000,000	35,000,000
Mortgages [Member] | Fixed Rate Debt
Secured Debt (Textual) [Abstract]
Debt instrument, maturity date range, start				9-Dec-15
Debt instrument, maturity date range, end				1-May-19
Notes payable minimum interest rates range				3.43%
Notes payable maximum interest rates range				5.94%
Secured Debt Including Debt on Real Estate Held for Sale					445,706,000
Weighted Average Interest Rate		5.46%
Mortgages [Member] | Variable Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale					63,595,000
Weighted Average Interest Rate		1.94%
Debt Assumed As Part of Acquisition [Member]
Secured Debt (Textual) [Abstract]
Amortization of Debt Discount (Premium)			4,900,000	5,100,000	5,100,000
Fannie Mae credit facilities | Fixed Rate Debt
Secured Debt (Textual) [Abstract]
Debt instrument, maturity date range, start				1-May-17
Debt instrument, maturity date range, end				1-Jul-23
Number of secured credit facilities				3
Credit facilities with aggregate commitment		834,300,000		834,300,000
Secured Debt Including Debt on Real Estate Held for Sale					626,667,000
Debt, Weighted Average Interest Rate		5.12%		5.12%
Fannie Mae credit facilities | Variable Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale					211,409,000
Interest rate at the end of the period		1.60%		1.60%
Tax-exempt secured notes payable | Variable Rate Debt
Secured Debt (Textual) [Abstract]
Debt instrument, maturity date range, start		1-Aug-19
Debt instrument, maturity date range, end		20-Mar-32
Notes payable minimum interest rates range				0.78%
Notes payable maximum interest rates range				0.93%
Unsecured Revolving Credit Facility due October 2015
Secured Debt (Textual) [Abstract]
Weighted Average Interest Rate		1.09%
Long-term Line of Credit		152,500,000		152,500,000	0
4.63% Medium-Term Notes due January 2022
Secured Debt (Textual) [Abstract]
Unamortized fair market adjustment		2,523,000		2,523,000	2,882,000
Weighted Average Interest Rate		4.63%
Fixed interest rate		4.63%		4.63%	4.63%
Senior Notes		397,477,000		397,477,000	397,118,000
2.68% Term Notes due December 2016
Secured Debt (Textual) [Abstract]
Weighted Average Interest Rate		1.53%
Fixed interest rate		1.53%		1.53%	2.68%
Senior Notes		100,000,000		100,000,000	65,000,000
ThreePointSevenTermNotesDueOctober2020 [Member]
Secured Debt (Textual) [Abstract]
Debt Instrument, Maturity Date						31-Oct-20
Debt Instrument, Face Amount					300,000,000
Senior Notes		299,954,000		299,954,000	299,946,000
Five Point One Three Percent, Medium Term Notes, Due January 2014 [Member]
Secured Debt (Textual) [Abstract]
Weighted Average Interest Rate		0.00%
Fixed interest rate		5.13%		5.13%	5.13%
Senior Notes		0		0	184,000,000
UDR Bank Credit Facility
Secured Debt (Textual) [Abstract]
Credit facilities with aggregate commitment		900,000,000		900,000,000	900,000,000
Increase in maximum borrowing capacity of unsecured revolving credit facility		1,450,000,000		1,450,000,000
Long-term Line of Credit		152,500,000		152,500,000	0
Interest rate at the end of the period		1.10%		1.10%	1.30%
Beginning of range of initial term of debt [Member] | Fannie Mae credit facilities
Secured Debt (Textual) [Abstract]
Debt Instrument, Term				7 years
End of range of inital term of debt [Member] | Fannie Mae credit facilities
Secured Debt (Textual) [Abstract]
Debt Instrument, Term				10 years
Fair Value, Measurements, Recurring [Member] | Line of Credit [Member] | Reported Value Measurement [Member] | Fannie Mae credit facilities | Fixed Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale		568,086,000		568,086,000
Fair Value, Measurements, Recurring [Member] | Line of Credit [Member] | Reported Value Measurement [Member] | Fannie Mae credit facilities | Variable Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale		266,196,000		266,196,000
Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Reported Value Measurement [Member] | Mortgages [Member] | Fixed Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale		401,210,000		401,210,000
Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Reported Value Measurement [Member] | Mortgages [Member] | Variable Rate Debt
Secured Debt (Textual) [Abstract]
Secured Debt Including Debt on Real Estate Held for Sale		$31,337,000		$31,337,000

IncomeLoss_Per_Share_Details

Income/(Loss) Per Share (Details) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income/(loss) from continuing operations attributable to common stockholders																	$0.59	($0.01)	($0.22)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	$6,485		$10,611		$4,359		($5,195)		($3,374)		$2,351		$4,525		($1,162)		$16,260	$2,340	($46,305)
Gain/(loss) on sales of real estate owned, net of tax																	143,572	0	0
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest																	-5,511	48	2,089
Income (Loss) from Continuing Operations Attributable to Parent																	154,324	2,448	-44,356
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest																	3	60	-140
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest																	5,511	1,530	7,986
Net (loss)/income attributable to common stockholders	64,486		39,618		29,076		17,430		35,769		2,257		4,261		-1,199		150,610	41,088	203,376
Net income/(loss)																	159,842	46,282	220,303
Premium on preferred stock redemption or repurchases, net																	0	0	-2,791
udr_IncomeLossContinuingOperationsAvailableToCommonShareholders																	150,600	-1,276	-53,157
Income/(loss) from discontinued operations, net of tax	0		79		18		-87		41,376		884		829		853		10	43,942	266,608
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest																	0	-1,578	-10,075
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent																	10	42,364	256,533
Weighted Average Number of Shares Issued, Basic																	252,707	250,684	239,482
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units																	-1,179	-715	-631
Weighted Average Number of Shares Outstanding, Basic and Diluted																	251,528	249,969	238,851
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic and Diluted Share																	$0	$0.17	$1.07
Net income/(loss) attributable to common stockholders b basic and diluted (in dollars per share)	$0.25	[1]	$0.16	[1]	$0.12	[1]	$0.07	[1]	$0.14	[1]	$0.01	[1]	$0.02	[1]	$0	[1]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements																	1,917	0	0
Weighted average number of common shares outstanding b diluted	256,000		253,732		252,191		251,822		249,987		251,454		251,406		249,917		253,445	249,969	238,851
Income/(loss) from discontinued operations attributable to common stockholders																	$0	$0.17	$1.07
Earnings Per Share, Diluted																	$0.59	$0.16	$0.85
Noncontrolling Interest
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest																	3	60	-140
Series G Preferred Stock [Member]
Dividends, Preferred Stock																	0	0	-2,286
Series E Preferred Stock [Member]
Dividends, Preferred Stock																	($3,724)	($3,724)	($3,724)
[1]	Quarterly income/(loss) per share amounts may not total to the annual amounts.

IncomeLoss_Per_Share_IncomeLos1

Income/(Loss) Per Share Income/(Loss) Per Share (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted Average Number Diluted Shares Outstanding Adjustment	0
OP Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	9,247,049	9,337,464	9,411,000
Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	3,035,548	3,035,548	3,036,000
Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,916,979	1,583,537	1,361,398

Stockholders_Equity_Details

Stockholders' Equity (Details) (USD $)	12 Months Ended				2 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2008	Feb. 19, 2015	31-May-12	31-May-07
Class of Stock [Line Items]
Shares Issued, Price Per Share	$29.95
Proceeds from Issuance of Common Stock	$102,100,000
Common stock, shares authorized	350,000,000	350,000,000
Preferred stock, shares authorized	50,000,000	50,000,000
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares	153,451
Common distributions declared per share	$1.04	$0.94	$0.88
Percentage distribution for not subject to domestic Federal income tax	0.9
Preferred stock, par or state value per share	$0	$0
Stock issued during period, shares, Distribution Reinvestment and Stock Purchase Plan				9,957,233
Shares reserved for issuance under the Stock Purchase Plan	10,963,730
Equity Distribution Agreement [Member]
Class of Stock [Line Items]
Common stock, shares authorized	20,000,000
Common Stock, Capital Shares Reserved for Future Issuance	16,518,567
Series E Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, liquidation preference per share	$16.61
Number of common stock shares to which each preferred share is convertible after special dividend	1.083
Declared preferred stock dividend	$1.33	$1.33	$1.33
Preferred stock, shares outstanding	2,803,812	2,803,812
Preferred stock, shares issued	2,803,812	2,803,812
Series F Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	20,000,000
Preferred stock, shares outstanding	2,464,183
Preferred stock, par or state value per share	$0.00
Preferred stock, value, issued	246
6.75% Series G Cumulative Redeemable Preferred Stock
Class of Stock [Line Items]
Declared preferred stock dividend	$0	$0	$0.57
Preferred stock, shares outstanding	0
Preferred stock, shares issued							5,400,000
Preferred stock, dividend rate			6.75%
Preferred stock, redemption price per share						$25
Stock stock, redemption amount						82,100,000
Preferred stock, shares redeemed			3,264,362
Preferred stock, redemption discount			2,791,000
Restricted Stock [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period Net of Forfeitures	860,811
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	873,010
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	12,199
Common Stock
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues	3,410,433		30,490,969
Issuance of stock during the period, shares, through Companybs 1999 Long-Term Incentive Plan, net of forfeitures	801,054	533,966	-22,224
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares	153,451	76,291	20,438
Subsequent Event [Member]
Class of Stock [Line Items]
Shares Issued, Price Per Share					$32.28
Proceeds from Issuance of Common Stock					$110,800,000
Subsequent Event [Member] | Common Stock
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues					3,432,936

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Options Outstanding, Number of Options
Balance, December 31, 2011	2,430,127
Granted	0
Balance, December 31, 2012	2,265,842
Options Outstanding, Weighted Average Exercise Price
Balance, December 31, 2011 (in dollars per share)	$12.63
Granted (in dollars per share)	$0
Exercised (in dollars per share)	$10.06
Forfeited (in dollars per share)	$0
Balance, December 31, 2012 (in dollars per share)	$12.82
Options Exercisable, Number of Options
Number of Options	2,265,842	2,430,127
Options Exercisable, Weighted Average Exercise Price
Weighted Average Exercise Price (in dollars per share)	$12.82	$12.63
Restricted Stock, Number Of shares
Vested	0
Restricted Stock, Weighted Average Fair Value Per Restricted Stock
Vested (in dollars per share)	$0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$2,500,000
Options Outstanding, Number of Options
Exercised	0
Options Outstanding, Weighted Average Exercise Price
Exercised (in dollars per share)	$0
Restricted Stock, Number Of shares
Balance, December 31, 2011	758,745
Granted	873,010
Vested	-619,578
Forfeited	-12,199
Balance, December 31, 2012	999,978
Restricted Stock, Weighted Average Fair Value Per Restricted Stock
Balance, December 31, 2011 (in dollars per share)	$23.89
Granted (in dollars per share)	$23.14
Vested (in dollars per share)	$22.70
Forfeited (in dollars per share)	$23.74
Balance, December 31, 2012 (in dollars per share)	$23.98
Outstanding [Member]
Options Outstanding, Number of Options
Exercised	-164,285
Exercisable [Member]
Options Outstanding, Number of Options
Exercised	164,285

Employee_Benefit_Plans_Details1

Employee Benefit Plans (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Issued	4,517,514
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,265,842	2,430,127
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$4,800,000
Number of share options exercisable	2,265,842	2,430,127
Range One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share options exercisable	1,830,672
Share options exercise price, lower range limit	$10.06
Range Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share options exercisable	404,291
Share options exercise price, lower range limit	$24.38
Range Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share options exercisable	30,879
Share options exercise price, upper range limit	$25.10
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total remaining compensation cost related to unvested share options	0
Stock based compensation expense	0	0	100,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total remaining compensation cost related to unvested share options	2,500,000
Weighted average remaining contractual life	1 year 1 month
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$23.14
Stock based compensation expense	4,200,000	3,600,000	3,700,000
Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total remaining compensation cost related to unvested share options	5,800,000
Weighted average remaining contractual life	1 year 10 months
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$21.15	$21.97
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	23.80%	15.80%
Stock based compensation expense	9,800,000	5,900,000	4,900,000
Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance under plan	19,000,000			16,000,000
Shares available for issuance under plan	10,067,371
Profit Sharing Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate provisions for contributions	$900,000	$900,000	$600,000

Income_Taxes_Details

Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Taxable Distributions Paid Per Common Share [Abstract]
Ordinary income	$0.70	$0.74	$0.17
Taxable Distributions Paid Per Common Share Qualified Ordinary Income	$0.14	$0	$0
Long-term capital gain	$0.11	$0.11	$0.19
Unrecapture section 1250 gain	$0.08	$0.07	$0.52
Taxable distributions per common share	$1.02	$0.93	$0.88

Income_Taxes_Details_1

Income Taxes (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current
Federal	$147	($1,030)	$1,961
State	550	846	1,463
Total current	697	-184	3,424
Deferred
Federal	20,138	-6,907	-21,479
State	5,159	-1,190	-3,021
Total deferred	25,297	-8,097	-24,500
Total income tax expense/(benefit)	25,994	-8,281	-21,076
Continuing Operations [Member]
Deferred
Total income tax expense/(benefit)	-15,098	-7,299	-30,282
Tax Benefit of Taxable Subsidiary			-30,717
Sale of Real Estate [Member]
Deferred
Total income tax expense/(benefit)	41,087	0	0
Discontinued Operations [Member]
Deferred
Total income tax expense/(benefit)	$5	($982)	$9,641

Income_Taxes_Details_2

Income Taxes (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred tax assets:
Federal and state tax attributes	$0	$13,069	$1,464
Book/tax depreciation	6,692	19,354	12,345
Construction capitalization differences	75	0	6,635
Investment in partnerships	0	0	3,112
Debt and interest deductions	0	10,311	0
Other	401	0	2,009
Total deferred tax assets	7,168	42,734	25,565
Valuation allowance	0	-1,310	-1,390
Net deferred tax assets	7,168	41,424	24,175
Deferred Tax Liabilities, Deferred Expense, Other Capitalized Costs	0	-3,766	0
Deferred Tax Liabilities, Investment in Noncontrolled Affiliates	0	-5,080	0
Deferred tax liabilities:
Other	-192	-305	0
Total deferred tax liabilities	-192	-9,151	0
Net deferred tax asset	$6,976	$32,273	$24,175

Income_Taxes_Details_3

Income Taxes (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%	35.00%
Income tax expense/(benefit)
U.S. federal income tax expense/(benefit)	$28,819,000	($8,493,000)	$21,853,000
State income tax provision	2,678,000	46,000	2,497,000
Other items	-137,000	246,000	-1,682,000
Income Tax (benefit)/expense, Conversion of certain TRS entities to REITs	-5,770,000	0	0
Valuation allowance	404,000	-80,000	-43,744,000
Total income tax expense/(benefit)	25,994,000	-8,281,000	-21,076,000
Unrecognized Tax Benefits	$0	$0

Income_Taxes_Details_Textual

Income Taxes (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%	35.00%
Valuation allowance	$0	$1,310,000	$1,390,000
Change in valuation allowance of deferred tax assets	400,000		44,400,000
Income Tax Expense (Benefit), Continuing Operations, Discontinued Operations, Extraordinary Items, Change	7,800,000
Income Tax (benefit)/expense, Conversion of certain TRS entities to REITs	-5,770,000	0	0
Unrecognized Tax Benefits	0	0
Internal Revenue Service (IRS)
Operating Loss Carryforwards [Line Items]
Net loss carryforwards	19,500,000
2020 through 2030 | State
Operating Loss Carryforwards [Line Items]
Net loss carryforwards	57,800,000
Prior to conversion [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	$1,700,000

Noncontrolling_Interests_Detai

Noncontrolling Interests (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Noncontrolling Interest [Line Items]
Net (loss)/income attributable to common stockholders	$64,486,000	$39,618,000	$29,076,000	$17,430,000	$35,769,000	$2,257,000	$4,261,000	($1,199,000)	$150,610,000	$41,088,000	$203,376,000
Acquisition of non-controlling interest											-4,871,000
Number of Apartment Homes Acquired		358
Change in equity from net loss income attributable to common stockholders and conversion of operating partnership units to companys common stock									154,982,000	42,905,000	203,905,000
Number of Communities Acquired		2
Redeemable noncontrolling interests in the Operating Partnership
Beginning redeemable non-controlling interests in the Operating Partnership				217,597,000				223,418,000	217,597,000	223,418,000
Mark to market adjustment to redeemable non-controlling interests in the Operating Partnership									73,954,000	3,656,000	-11,392,000
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership									-4,372,000	-1,817,000	-529,000
Net income attributable to redeemable non-controlling interests in the Operating Partnership									5,511,000	1,530,000	7,986,000
Distributions to redeemable non-controlling interests in the Operating Partnership									-10,077,000	-9,440,000
Ending redeemable non-controlling interests in the Operating Partnership					217,597,000					217,597,000	223,418,000
Net income/(loss) attributable to non-controlling interests									-3,000	-60,000	140,000
Noncontrolling Interest
Noncontrolling Interest [Line Items]
Acquisition of non-controlling interest										-4,900,000	-4,871,000
Redeemable noncontrolling interests in the Operating Partnership
Net income/(loss) attributable to non-controlling interests									-3,000	-60,000	140,000
Operating Community [Member] | Noncontrolling Interest
Noncontrolling Interest [Line Items]
Acquisition of non-controlling interest										-4,000,000
Number of Apartment Homes Acquired										434
Development Community [Member] | Noncontrolling Interest
Noncontrolling Interest [Line Items]
Acquisition of non-controlling interest										-900,000
RedeemableNoncontrollingInterest [Member]
Redeemable noncontrolling interests in the Operating Partnership
Other Comprehensive (Income) Loss, Net of Tax, Portion Attributable to Noncontrolling Interest									($133,000)	$250,000	$80,000
Corporate Joint Venture [Member]
Noncontrolling Interest [Line Items]
Number of Communities Acquired										2
Operating Community [Member]
Noncontrolling Interest [Line Items]
Number of Communities Acquired										1

Fair_Value_of_Derivatives_and_4

Fair Value of Derivatives and Financial Instruments (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable, Net	$14,369		$83,033
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset	88		0
Derivative Asset Designated as Hedging Instrument, Fair Value	88		0
Derivative Liability			4,965
Derivatives - Interest rate contracts	10,368		4,965
Secured debt instruments - variable rate
Long-term Line of Credit	1,900		2,200
Unsecured debt instruments
Redeemable Noncontrolling Interest, Equity, Carrying Amount			217,597		223,418
Redeemable non-controlling interests in operating partnership	282,480		217,597
Carrying Amount | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable, Net	14,369		83,033
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	14,457		83,033
Unsecured debt instruments
Total liabilities	3,593,473		3,528,668
Redeemable Noncontrolling Interest, Equity, Carrying Amount	282,480
Redeemable non-controlling interests in operating partnership			217,597	[1]
Carrying Amount | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Liability	10,368
Derivatives - Interest rate contracts			4,965	[2]
Carrying Amount | Mortgages [Member] | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate			445,706	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate			63,595	[3]
Carrying Amount | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate			94,700	[3]
Carrying Amount | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate			626,667	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate			211,409	[3]
Carrying Amount | Senior unsecured notes | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	2,069,076		2,081,626	[3]
Fair Value | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	14,808		83,833
Total assets	14,896		83,833
Unsecured debt instruments
Total liabilities	3,721,512		3,651,141
Redeemable non-controlling interests in operating partnership	282,480	[1]	217,597	[1]
Fair Value | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	88
Derivatives - Interest rate contracts	10,368	[1]	4,965	[2]
Fair Value | Mortgages [Member] | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	415,663	[2]	466,375	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate	31,337	[2]	63,595	[3]
Fair Value | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	94,700	[2]	94,700	[3]
Fair Value | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	606,623	[2]	661,094	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate	266,196	[2]	211,409	[3]
Fair Value | Senior unsecured notes | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	2,144,125	[3]	2,149,003	[3]
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	0		0
Total assets	0		0
Unsecured debt instruments
Total liabilities	0		0
Redeemable non-controlling interests in operating partnership	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	0
Derivatives - Interest rate contracts	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Mortgages [Member] | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Commercial bank | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Senior unsecured notes | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	0		0
Total assets	88		0
Unsecured debt instruments
Total liabilities	10,368		4,965
Redeemable non-controlling interests in operating partnership	282,480	[1]	217,597
Fair Value | Significant Other Observable Inputs (Level 2) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	88
Derivatives - Interest rate contracts	10,368
Fair Value | Significant Other Observable Inputs (Level 2) | Mortgages [Member] | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Commercial bank | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	0
Fair Value | Significant Other Observable Inputs (Level 2) | Senior unsecured notes | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	0		0
Fair Value | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Notes receivable	14,808		83,833
Total assets	14,808		83,833
Unsecured debt instruments
Total liabilities	3,711,144		3,646,176
Redeemable non-controlling interests in operating partnership	0		0
Fair Value | Significant Unobservable Inputs (Level 3) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset Designated as Hedging Instrument, Fair Value	0
Derivatives - Interest rate contracts	0		0
Fair Value | Significant Unobservable Inputs (Level 3) | Mortgages [Member] | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	415,663		466,375
Secured debt instruments - variable rate
Secured debt instruments - variable rate	31,337		63,595
Fair Value | Significant Unobservable Inputs (Level 3) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	94,700		94,700
Fair Value | Significant Unobservable Inputs (Level 3) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	606,623		661,094
Secured debt instruments - variable rate
Secured debt instruments - variable rate	266,196		211,409
Fair Value | Significant Unobservable Inputs (Level 3) | Commercial bank | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	152,500
Fair Value | Significant Unobservable Inputs (Level 3) | Senior unsecured notes | Fair Value, Measurements, Recurring
Unsecured debt instruments
Unsecured debt instruments	2,144,125		2,149,003
Fixed Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	969,296		1,072,373
Variable Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	392,233		369,704
Unsecured Revolving Credit Facility due October 2015
Secured debt instruments - variable rate
Long-term Line of Credit	152,500		0
Tax-exempt secured notes payable | Variable Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale			94,700
Tax-exempt secured notes payable | Variable Rate Debt | Carrying Amount | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	94,700
Line of Credit [Member] | Fixed Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale			626,667
Line of Credit [Member] | Fixed Rate Debt | Carrying Amount | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	568,086
Line of Credit [Member] | Variable Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale			211,409
Line of Credit [Member] | Variable Rate Debt | Carrying Amount | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	266,196
Mortgages [Member] | Fixed Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale			445,706
Mortgages [Member] | Fixed Rate Debt | Carrying Amount | Mortgages [Member] | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	401,210
Mortgages [Member] | Variable Rate Debt
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale			63,595
Mortgages [Member] | Variable Rate Debt | Carrying Amount | Mortgages [Member] | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Secured Debt Including Debt on Real Estate Held for Sale	$31,337
[1]	See Note 6, Secured Debt and Unsecured Debt.
[2]	See Note 2, Significant Accounting Policies.
[3]	See Note 13, Derivatives and Hedging Activity.

Derivatives_and_Hedging_Activi4

Derivatives and Hedging Activity (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified	instruments
Designated as Hedging Instrument | Interest rate swaps
Derivative [Line Items]
Number of Instruments	14
Derivative, Notional Amount	$365,000
Designated as Hedging Instrument | Interest rate caps
Derivative [Line Items]
Number of Instruments	3
Derivative, Notional Amount	243,079
Not Designated as Hedging Instrument | Interest rate caps
Derivative [Line Items]
Number of Instruments	1
Derivative, Notional Amount	$96,409

Derivatives_and_Hedging_Activi5

Derivatives and Hedging Activity (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet
Derivative Asset Designated as Hedging Instrument, Fair Value	$88	$0
Derivative Liability Designated as Hedging Instrument, Fair Value	10,368	4,965
Interest rate products | Other assets | Designated as Hedging Instrument
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet
Derivative Asset Designated as Hedging Instrument, Fair Value	86	0
Interest rate products | Other assets | Not Designated as Hedging Instrument
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet
Derivative Asset Not Designated as Hedging Instrument, Fair Value	2	0
Interest rate products | Other liabilities | Designated as Hedging Instrument
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet
Derivative Liability Designated as Hedging Instrument, Fair Value	10,368	4,965
Interest rate products | Other liabilities | Not Designated as Hedging Instrument
Fair value of Company's derivative financial instruments and their classification on Consolidated Balance Sheet
Derivative Liability Not Designated as Hedging Instrument, Fair Value	$0	$0

Derivatives_and_Hedging_Activi6

Derivatives and Hedging Activity (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effect of derivative instruments on the Consolidated Statements of Operations
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total	($4,834,000)	($6,851,000)	($7,649,000)
Interest rate products | Cash Flow Hedging
Effect of derivative instruments on the Consolidated Statements of Operations
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net, Total	-8,695,000	-469,000	-4,924,000
Interest rate products | Interest expense | Cash Flow Hedging
Effect of derivative instruments on the Consolidated Statements of Operations
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total	-4,834,000	-6,851,000	-7,649,000
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net, Total	3,000		0
Interest rate products | Other income/(expense)
Effect of derivative instruments on the Consolidated Statements of Operations
Derivative Instruments, Gain (Loss) Recognized in Income, Net, Total	($4,000)	$271,000	$290,000

Derivatives_and_Hedging_Activi7

Derivatives and Hedging Activity Derivatives and Hedging Activity (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]
Derivative Liability Designated as Hedging Instrument, Fair Value	$10,368	$4,965
Derivative Liability, Not Subject to Master Netting Arrangement	0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	10,341	4,965
Derivative Liability		4,965
Derivative, Collateral, Right to Reclaim Securities	-27	0
Derivative, Collateral, Right to Reclaim Cash	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	88	0
Derivative Asset, Not Subject to Master Netting Arrangement	0	0
Derivative Asset	88	0
Derivative, Collateral, Obligation to Return Securities	-27	0
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	$61	$0

Derivatives_and_Hedging_Activi8

Derivatives and Hedging Activity (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative [Line Items]
Derivative, Collateral, Obligation to Return Cash	$0	$0
Derivatives And Hedging Activity (Textual) [Abstract]
Cash flow hedge ineffectiveness in earnings materiality	3000	less than $1,000	less than a B $1,000
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	5,000,000
Fair value of derivatives in a net liability position	10,600,000
Payment required to pay for contract termination	$10,600,000

Commitments_and_Contingencies_3

Commitments and Contingencies (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Long-term Purchase Commitment [Line Items]
Number of Properties	2
Costs Incurred to Date	549,130
Expected Costs to Complete	255,747	[1]
Wholly-owned b under development
Long-term Purchase Commitment [Line Items]
Number of Properties	1
Costs Incurred to Date	177,632
Purchase Commitment, Remaining Minimum Amount Committed	40,068
Average Ownership Stake	100.00%
Wholly-owned b redevelopment
Long-term Purchase Commitment [Line Items]
Number of Properties	1
Costs Incurred to Date	83,778
Purchase Commitment, Remaining Minimum Amount Committed	14,222
Average Ownership Stake	100.00%
Unconsolidated joint ventures
Long-term Purchase Commitment [Line Items]
Number of Properties	3
Costs Incurred to Date	225,013
Purchase Commitment, Remaining Minimum Amount Committed	172,155
Participating Loan Investment Steele Creek Denver Colorado [Member]
Long-term Purchase Commitment [Line Items]
Number of Properties	1
Costs Incurred to Date	62,707
Purchase Commitment, Remaining Minimum Amount Committed	29,302
Average Ownership Stake	0.00%
[1]	Represents 100% of project costs incurred to date.

Commitments_and_Contingencies_4

Commitments and Contingencies (Details 1) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Ground Leases
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2013	$5,412	[1]
2014	5,412	[1]
2015	5,412	[1]
2016	5,412	[1]
2017	5,412	[1]
Thereafter	313,735	[1]
Total	340,795	[1]
Office Space
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2013	709
2014	124
2015	76
2016	76
2017	76
Thereafter	109
Total	$1,170
[1]	For purposes of our ground lease contracts, the Company uses the minimum lease payment, if stated in the agreement. For ground lease agreements where there is a reset provision based on the communities appraised value or consumer price index but does not include a specified minimum lease payment, the Company uses the current rent over the remainder of the lease term.

Commitments_and_Contingencies_5

Commitments and Contingencies (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	Communities
Ground Leases
Real Estate Properties [Line Items]
Number of Real Estate Properties	6
Rent expense	$5,400,000	$5,200,000	$5,100,000
Office Space
Real Estate Properties [Line Items]
Rent expense	1,300,000	1,300,000	1,100,000
Wholly-owned b under development
Real Estate Properties [Line Items]
Capital Expenditures Incurred but Not yet Paid	$14,700,000
Number of Real Estate Properties	1

Reportable_Segments_Details

Reportable Segments (Details) (USD $)	12 Months Ended			3 Months Ended							9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2011	Dec. 31, 2009
	Segments
Reportable Segment (Textual) [Abstract]
Number of reportable segments	2
Condition for Community considered to have stabilized occupancy	90% occupancy for at least three consecutive months
Number of tenants or related group of tenants that contributed 10% or more of company total revenue	0	0	0
Reportable apartment home segment rental income	$818,046,000	$758,926,000	$716,612,000
Reportable apartment home segment NOI	556,321,000	514,041,000	504,200,000
Joint Venture Managment and Other Fees	13,044,000	12,442,000	11,911,000
Reconciling items:
Property management	-22,142,000	-20,780,000	-20,465,000
Other operating expenses	-8,271,000	-7,136,000	-5,718,000
Depreciation and amortization	-358,154,000	-341,490,000	-350,401,000
General and administrative	-47,800,000	-42,238,000	-43,792,000
Casualty-related (recoveries)/charges, net	-541,000	12,253,000	-8,495,000
Other depreciation and amortization	-5,775,000	-6,741,000	-4,105,000
Income/(loss) from unconsolidated entities	-7,006,000	-415,000	-8,579,000
Interest Expense	-130,454,000	-126,083,000	-138,792,000
Interest and Other Income Including Discontinued Operations	11,837,000	4,681,000	2,703,000
Tax benefit/(expense) of taxable REIT subsidiary, net	15,136,000	7,299,000	30,282,000
Gain Loss on the Sale of Real Estate, Including Discontinued Operations	143,647,000	41,919,000	251,554,000
Redeemable non-controlling interests in OP	-5,511,000	-1,530,000	-7,986,000
Noncontrolling Interest in Net Income (Loss) Other Noncontrolling Interests, Nonredeemable	-3,000	-60,000	140,000
Net income/(loss) attributable to Entity	154,334,000	44,812,000	212,177,000
Reportable apartment home segment assets:
Total segment assets	8,383,259,000	8,207,977,000		8,383,259,000				8,207,977,000
Accumulated depreciation	-2,434,772,000	-2,208,794,000		-2,434,772,000				-2,208,794,000
Total real estate owned, net of accumulated depreciation	5,948,487,000	5,999,183,000		5,948,487,000				5,999,183,000
Reconciling items:
Cash and cash equivalents	15,224,000	30,249,000	12,115,000	15,224,000				30,249,000				12,503,000
Restricted cash	22,340,000	22,796,000		22,340,000				22,796,000
Deferred financing costs, net	22,686,000	26,924,000		22,686,000				26,924,000
Notes receivable	14,369,000	83,033,000		14,369,000				83,033,000
Redeemable Noncontrolling Interest, Equity, Common, Carrying Amount	718,226,000	507,655,000		718,226,000				507,655,000
Other assets	105,202,000	137,882,000		105,202,000				137,882,000
Total assets	6,846,534,000	6,807,722,000		6,846,534,000				6,807,722,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	326,461,000	452,057,000	422,480,000
Same Communities
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	55,300,000	47,500,000	46,400,000
Same Communities Western Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	245,803,000	231,156,000	218,268,000
Reportable apartment home segment NOI	178,926,000	166,033,000	154,205,000
Reportable apartment home segment assets:
Total segment assets	2,358,444,000	2,337,980,000		2,358,444,000				2,337,980,000
Same Communities Mid-Atlantic Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	161,566,000	160,208,000	155,777,000
Reportable apartment home segment NOI	111,762,000	111,643,000	108,490,000
Reportable apartment home segment assets:
Total segment assets	1,410,156,000	1,395,772,000		1,410,156,000				1,395,772,000
Same Communities Southeastern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	107,991,000	102,988,000	97,699,000
Reportable apartment home segment NOI	71,528,000	67,264,000	63,122,000
Reportable apartment home segment assets:
Total segment assets	786,438,000	785,134,000		786,438,000				785,134,000
Same Communities Southwestern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	54,810,000	52,302,000	46,800,000
Reportable apartment home segment NOI	33,725,000	31,927,000	27,878,000
Reportable apartment home segment assets:
Total segment assets	440,721,000	434,875,000		440,721,000				434,875,000
Same Communities Northeast Region [Member]
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	60,796,000	58,075,000	54,461,000
Reportable apartment home segment NOI	44,897,000	42,350,000	39,377,000
Reportable apartment home segment assets:
Total segment assets	746,550,000	738,805,000		746,550,000				738,805,000
Non-Mature communities/Other
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	174,183,000	150,907,000	171,239,000
Reportable apartment home segment NOI	115,483,000	94,824,000	111,128,000
Reportable apartment home segment assets:
Total segment assets	2,640,950,000	2,515,411,000		2,640,950,000				2,515,411,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	8,100,000	8,300,000	8,700,000
Total Communities [Member]
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	805,149,000	755,636,000	744,244,000
Segment Reconciling Items [Member]
Reconciling items:
Gain Loss on the Sale of Real Estate, Including Discontinued Operations		40,449,000
United Dominion Reality L.P.
Reportable Segment (Textual) [Abstract]
Related party management fee percentage	2.75%
Number of reportable segments	2
Condition for Community considered to have stabilized occupancy	once it achieves 90% occupancy for at least three consecutive months
Number of tenants or related group of tenants that contributed 10% or more of company total revenue	0		0
Reportable apartment home segment rental income	422,634,000	410,842,000	400,691,000
Reportable apartment home segment NOI	300,313,000	287,535,000	281,538,000
Reconciling items:
Property management	-11,622,000	-11,298,000	-11,019,000
Other operating expenses	-5,172,000	-5,728,000	-5,272,000
Depreciation and amortization	-179,176,000	-181,302,000	-195,051,000
Interest	-41,717,000	-36,058,000	-45,234,000
General and administrative	-28,541,000	-24,808,000	-26,204,000
Casualty-related (recoveries)/charges, net	-541,000	8,083,000	-5,518,000
Noncontrolling Interest in Net Income (Loss) Other Noncontrolling Interests, Nonredeemable	952,000	4,566,000	352,000
Net (loss)/gain on sale of depreciable property	63,635,000	41,518,000	51,094,000
Net income/(loss) attributable to Entity	96,227,000	73,376,000	43,982,000	32,631,000	8,637,000	24,426,000	30,533,000	44,482,000	10,154,000	7,729,000	11,011,000
Reportable apartment home segment assets:
Total segment assets	4,238,770,000	4,188,480,000		4,238,770,000				4,188,480,000
Accumulated depreciation	-1,403,303,000	-1,241,574,000		-1,403,303,000				-1,241,574,000
Total real estate owned, net of accumulated depreciation	2,835,467,000	2,946,906,000		2,835,467,000				2,946,906,000
Reconciling items:
Cash and cash equivalents	502,000	1,897,000	2,804,000	502,000				1,897,000					704,000
Restricted cash	13,811,000	13,526,000		13,811,000				13,526,000
Deferred financing costs, net	4,475,000	5,848,000		4,475,000				5,848,000
Other assets	24,029,000	25,064,000		24,029,000				25,064,000
Total assets	2,878,284,000	2,993,241,000		2,878,284,000				2,993,241,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	91,682,000	151,002,000	115,355,000
United Dominion Reality L.P. | Same Communities
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	32,800,000	25,800,000
United Dominion Reality L.P. | Same Communities Western Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	194,105,000	181,935,000	172,096,000
Reportable apartment home segment NOI	142,388,000	131,276,000	122,477,000
Reportable apartment home segment assets:
Total segment assets	1,749,494,000	1,733,144,000		1,749,494,000				1,733,144,000
United Dominion Reality L.P. | Same Communities Mid-Atlantic Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	68,822,000	68,205,000	66,487,000
Reportable apartment home segment NOI	46,639,000	46,770,000	45,801,000
Reportable apartment home segment assets:
Total segment assets	713,093,000	706,447,000		713,093,000				706,447,000
United Dominion Reality L.P. | Same Communities Southeastern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	45,224,000	43,208,000	40,771,000
Reportable apartment home segment NOI	29,815,000	28,105,000	26,510,000
Reportable apartment home segment assets:
Total segment assets	333,428,000	328,150,000		333,428,000				328,150,000
United Dominion Reality L.P. | Same Communities Southwestern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	26,580,000	25,614,000	23,980,000
Reportable apartment home segment NOI	16,821,000	16,057,000	14,738,000
Reportable apartment home segment assets:
Total segment assets	228,996,000	226,252,000		228,996,000				226,252,000
United Dominion Reality L.P. | Same Communities Northeast Region [Member]
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	38,087,000	36,623,000	34,579,000
Reportable apartment home segment NOI	28,930,000	27,149,000	25,653,000
Reportable apartment home segment assets:
Total segment assets	447,269,000	443,483,000		447,269,000				443,483,000
United Dominion Reality L.P. | Non-Mature communities/Other
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	49,816,000	55,257,000	62,778,000
Reportable apartment home segment NOI	35,720,000	38,178,000	46,359,000
Reportable apartment home segment assets:
Total segment assets	766,490,000	751,004,000		766,490,000				751,004,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	$1,000,000	$2,000,000
United Dominion Reality L.P. | Minimum
Reportable Segment (Textual) [Abstract]
Percent occupancy to be considered a community	90.00%
Time to maintain percent occupancy to be considered a community	3 months
United Dominion Reality L.P. | Taxable REIT Subsidiaries
Reportable Segment (Textual) [Abstract]
Related party management fee percentage	2.75%

Hurricane_Related_Charges_Deta

Hurricane Related Charges (Details) (USD $)	12 Months Ended			4 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 30, 2013
Hurricane Related Charges [Line Items]
Casualty-related (recoveries)/charges, net	($541,000)	$12,253,000	($8,495,000)
Other Cost and Expense, Operating	8,271,000	7,136,000	5,718,000
Proceeds from Insurance Settlement, Investing Activities		2,600,000	4,200,000
Casualty-related (recoveries)/charges, net	-541,000	12,253,000	-8,495,000
New York Properties [Member]
Hurricane Related Charges [Line Items]
Number of Communities Owned			3
Number of Apartments Owned			1,706
Impairment of Long-Lived Assets Held-for-use		0	9,000,000
Other Cost and Expense, Operating			10,400,000
Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Total Estimated Insurance Recovery			14,500,000
Casualty-related (recoveries)/charges, net		4,800,000
Other Nonrecurring Expense		3,400,000	4,400,000
Hurricane Sandy [Member] | Casualty Gain [Member]
Hurricane Related Charges [Line Items]
Casualty-related (recoveries)/charges, net		654,000
Hurricane Sandy [Member] | Rent concessions
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			3,600,000
Hurricane Sandy [Member] | Rent not contractually receivable
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			767,000
United Dominion Reality L.P.
Hurricane Related Charges [Line Items]
Other Cost and Expense, Operating	5,172,000	5,728,000	5,272,000
Casualty-related (recoveries)/charges, net	-541,000	8,083,000	-5,518,000
United Dominion Reality L.P. | New York Properties [Member]
Hurricane Related Charges [Line Items]
Number of Communities Owned			2
Number of Apartments Owned			1,001
United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Impairment of Long-Lived Assets Held-for-use		0	7,100,000
Other Cost and Expense, Operating			7,000,000
Total Estimated Insurance Recovery		10,800,000	10,800,000
Casualty-related (recoveries)/charges, net		3,300,000
Other Nonrecurring Expense		2,100,000	2,200,000
United Dominion Reality L.P. | Hurricane Sandy [Member] | Casualty Gain [Member]
Hurricane Related Charges [Line Items]
Casualty-related (recoveries)/charges, net		582,000
United Dominion Reality L.P. | Hurricane Sandy [Member] | Rent concessions
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			1,800,000
United Dominion Reality L.P. | Hurricane Sandy [Member] | Rent not contractually receivable
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			400,000
Business Interruption [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		6,800,000
Business Interruption [Member] | United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		4,200,000
FY 2012 [Member] | Business Interruption [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		4,200,000
FY 2012 [Member] | Business Interruption [Member] | United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		2,100,000
FY 2013 [Member] | Business Interruption [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		2,600,000
FY 2013 [Member] | Business Interruption [Member] | United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities				$2,100,000

Unaudited_Summarized_Consolida4

Unaudited Summarized Consolidated Quarterly Financial Data Unaudited Summarized Consolidated Quarterly Financial Data (Details) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Data [Abstract]
Rental income	$206,104	[1]	$203,587	[1]	$200,959	[1]	$194,352	[1]	$190,321	[1]	$187,917	[1]	$186,285	[1]	$181,961	[1]
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	6,485		10,611		4,359		-5,195		-3,374		2,351		4,525		-1,162		16,260	2,340	-46,305
Income/(loss) from discontinued operations, net of tax	0		79		18		-87		41,376		884		829		853		10	43,942	266,608
Net (loss)/income attributable to stakeholders	$64,486		$39,618		$29,076		$17,430		$35,769		$2,257		$4,261		($1,199)		$150,610	$41,088	$203,376
Earnings per weighted average common share - basic and diluted:
Net (loss)/income attributable to common stockholders b basic and diluted (in dollars per share)	$0.25	[2]	$0.16	[2]	$0.12	[2]	$0.07	[2]	$0.14	[2]	$0.01	[2]	$0.02	[2]	$0	[2]
Weighted Average Number of Shares Outstanding, Basic	253,983		251,655		250,255		250,177		249,987		249,985		249,985		249,917		251,528	249,969	238,851
Weighted average number of common shares outstanding b diluted	256,000		253,732		252,191		251,822		249,987		251,454		251,406		249,917		253,445	249,969	238,851
[1]	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
[2]	Quarterly income/(loss) per share amounts may not total to the annual amounts.

Consolidation_and_Basis_of_Pre3

Consolidation and Basis of Presentation (UNITED DOMINION REALTY, L.P.) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Markets
	Apartment_Homes
Consolidation and Basis of Presentation [Line Items]
Number of markets operating within	20
Number of apartments owned	39,851
Operating Partnership outstanding units	183,278,698	183,278,698
OP units outstanding related to limited partner	183,278,698	183,278,698	184,281,254	184,281,254
United Dominion Reality L.P.
Consolidation and Basis of Presentation [Line Items]
Rental revenues percent of General Partner's consolidated rental revenues	52.00%	54.00%	54.00%
Number of markets operating within	17
Number of apartments owned	20,814
OP units outstanding related to general partner	110,883	110,883
Percentage of total outstanding Operating Partnership units represented by General Partnership units outstanding	0.06%
OP units outstanding related to limited partner	183,167,815	183,167,815
UDR, Inc.
Consolidation and Basis of Presentation [Line Items]
OP units outstanding related to limited partner	174,002,342	173,848,891
Percentage of units outstanding owned by limited partners	95.00%	94.90%
Non-affiliated Partners
Consolidation and Basis of Presentation [Line Items]
OP units outstanding related to limited partner	9,165,473	9,318,924
Percentage of units outstanding owned by limited partners	5.00%	5.10%
Class A Limited Partner
Consolidation and Basis of Presentation [Line Items]
OP units outstanding related to limited partner	1,751,671
Class A Limited Partner | United Dominion Reality L.P.
Consolidation and Basis of Presentation [Line Items]
OP units outstanding related to limited partner	1,873,332	1,751,671

Consolidation_and_Basis_of_Pre4

Consolidation and Basis of Presentation (UNITED DOMINION REALTY, L.P.) Consolidation and Basis of Presentation (UNITED DOMINION REALTY, L.P. - Phantoms) (Details)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Limited partnership units owned	183,278,698	183,278,698	184,281,254	184,281,254
United Dominion Reality L.P.
General Partners' Capital Account, Units Outstanding	110,883	110,883
Limited partnership units owned	183,167,815	183,167,815

Significant_Accounting_Policie6

Significant Accounting Policies (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting Policies [Line Items]
Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company			0.1
Development costs excluding direct costs and capitalized interest	$8,953,000	$11,100,000	$10,000,000
Interest capitalized during period	20,200,000	29,400,000	26,400,000
Advertising expense	6,000,000	5,700,000	6,200,000
Minimum | Buildings
Accounting Policies [Line Items]
Estimated useful lives	35 years
Minimum | Building improvements
Accounting Policies [Line Items]
Estimated useful lives	10 years
Minimum | Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	3 years
Maximum | Buildings
Accounting Policies [Line Items]
Estimated useful lives	55 years
Maximum | Building improvements
Accounting Policies [Line Items]
Estimated useful lives	35 years
Maximum | Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	10 years
United Dominion Reality L.P.
Accounting Policies [Line Items]
Cumulative Adjustment to Net Income Attributable to Noncontrolling Interest		3,300,000
Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company	0.1
Development costs excluding direct costs and capitalized interest	2,010,000	2,500,000	2,100,000
Interest capitalized during period	2,900,000	5,900,000	3,700,000
Advertising expense	$2,500,000	$2,500,000	$2,400,000
United Dominion Reality L.P. | Minimum | Buildings
Accounting Policies [Line Items]
Estimated useful lives	35 years
United Dominion Reality L.P. | Minimum | Building improvements
Accounting Policies [Line Items]
Estimated useful lives	10 years
United Dominion Reality L.P. | Minimum | Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	3 years
United Dominion Reality L.P. | Maximum | Buildings
Accounting Policies [Line Items]
Estimated useful lives	55 years
United Dominion Reality L.P. | Maximum | Building improvements
Accounting Policies [Line Items]
Estimated useful lives	35 years
United Dominion Reality L.P. | Maximum | Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	10 years

Real_Estate_Owned_UNITED_DOMIN2

Real Estate Owned (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Summary of carrying amounts for real estate owned (at cost)
Land	$1,980,221	$1,847,127
Under development:
Real estate under development (net of accumulated depreciation of $0)	177,632	466,002
Real estate owned	8,383,259	8,207,977
Accumulated depreciation	-2,434,772	-2,208,794	-1,924,682	-1,831,727
Total real estate owned, net of accumulated depreciation	5,948,487	5,999,183
Land
Held for sale:
Sold or held for sale	0	10,751
Under development:
Real estate under development (net of accumulated depreciation of $0)	24,584	110,769
Building and improvements
Held for sale:
Sold or held for sale	0	5,969
Construction in progress
Under development:
Real estate under development (net of accumulated depreciation of $0)	153,048	356,644
United Dominion Reality L.P.
Summary of carrying amounts for real estate owned (at cost)
Land	1,008,014	1,004,447
Depreciable property - held and used:
Building and improvements	3,230,756	3,103,970
Under development:
Real estate under development (net of accumulated depreciation of $0)	0	80,063
Real estate owned	4,238,770	4,188,480
Accumulated depreciation	-1,403,303	-1,241,574	-1,097,133	-976,358
Total real estate owned, net of accumulated depreciation	2,835,467	2,946,906
United Dominion Reality L.P. | Land
Under development:
Real estate under development (net of accumulated depreciation of $0)	0	9,447
United Dominion Reality L.P. | Construction in progress
Under development:
Real estate under development (net of accumulated depreciation of $0)	$0	$70,616

Real_Estate_Owned_UNITED_DOMIN3

Real Estate Owned (UNITED DOMINION REALTY, L.P.) (Details Textual) (USD $)	3 Months Ended	12 Months Ended			3 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012
		Communities
		Apartment_Homes
Real Estate Properties [Line Items]
Number of States in which Entity Operates		10
Real Estate Owned (Textual) [Abstract]
Number of apartments owned		39,851
Number of communities acquired apartment homes are within		0
Number of apartment homes acquired	358
Development costs excluding direct costs and capitalized interest		$8,953,000	$11,100,000	$10,000,000
Capitalized Interest Costs, Including Allowance for Funds Used During Construction		20,200,000	29,400,000	26,400,000
Other Cost and Expense, Operating		8,271,000	7,136,000	5,718,000
Communities Sold		9
Proceeds from Sale of Property, Plant, and Equipment		328,400,000	81,100,000	609,400,000
Gain (Loss) on Disposition of Property Plant Equipment		138,600,000
Payments for (Proceeds from) Investments		-383,886,000	-250,043,000	-593,167,000
Gain/(loss) on sales of real estate owned		143,572,000	0	0
United Dominion Reality L.P.
Real Estate Properties [Line Items]
Number of States in which Entity Operates		9
Real Estate Owned (Textual) [Abstract]
Number of apartments owned		20,814
Development costs excluding direct costs and capitalized interest		2,010,000	2,500,000	2,100,000
Capitalized Interest Costs, Including Allowance for Funds Used During Construction		2,900,000	5,900,000	3,700,000
Other Cost and Expense, Operating		5,172,000	5,728,000	5,272,000
Communities Sold		1	2		4
Proceeds from Sale of Property, Plant, and Equipment		48,700,000	81,100,000
Gain (Loss) on Disposition of Property Plant Equipment		24,400,000
Payments for (Proceeds from) Investments		-47,922,000
Gain/(loss) on sales of real estate owned		63,635,000	0	0
New York Properties [Member]
Real Estate Owned (Textual) [Abstract]
Number of Communities Owned				3	3
Number of Apartments Owned				1,706	1,706
Impairment of Long-Lived Assets Held-for-use			0	9,000,000
Other Cost and Expense, Operating				10,400,000
New York Properties [Member] | United Dominion Reality L.P.
Real Estate Owned (Textual) [Abstract]
Number of Communities Owned				2	2
Number of Apartments Owned				1,001	1,001
Hurricane Sandy [Member]
Real Estate Owned (Textual) [Abstract]
Total Estimated Insurance Recovery				14,500,000
Hurricane Sandy [Member] | United Dominion Reality L.P.
Real Estate Owned (Textual) [Abstract]
Impairment of Long-Lived Assets Held-for-use			0	7,100,000
Other Cost and Expense, Operating				7,000,000
Total Estimated Insurance Recovery			10,800,000	10,800,000
Unconsolidated Joint Venture Four Texas [Member] | United Dominion Reality L.P.
Real Estate Owned (Textual) [Abstract]
Communities Sold		2
Gain (Loss) on Disposition of Property Plant Equipment		$39,200,000

Discontinued_Operations_UNITED2

Discontinued Operations (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	3 Months Ended								12 Months Ended			3 Months Ended		9 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012	Mar. 31, 2012	Sep. 30, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Property Plant Equipment									$138,600,000
Discontinued Operations (Textual) [Abstract]
Number of communities sold									9
Number of apartment homes sold									2,500	914	6,507
Proceeds from Sale of Property, Plant, and Equipment									328,400,000	81,100,000	609,400,000
Summary of income from discontinued operations
Rental income									147,000	9,152,000	39,543,000
Rental expenses									225,000	3,511,000	14,106,000
Property management fee									4,000	252,000	1,087,000
Real estate depreciation									0	1,958,000	8,475,000
Interest									21,000	-62,000	821,000
Income before net gain on the sale of property									-103,000	3,493,000	15,054,000
Income/(loss) from discontinued operations	0	79,000	18,000	-87,000	41,376,000	884,000	829,000	853,000	10,000	43,942,000	266,608,000
United Dominion Reality L.P.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Property Plant Equipment									24,400,000
Discontinued Operations (Textual) [Abstract]
Number of communities sold									1	2		4
Number of apartment homes sold										914			1,314
Proceeds from Sale of Property, Plant, and Equipment									48,700,000	81,100,000
Number of communities held for sale	0								0
Summary of income from discontinued operations
Rental income									0	8,989,000	15,745,000
Rental expenses									0	3,149,000	5,444,000
Property management fee									0	247,000	432,000
Real estate depreciation									0	1,935,000	3,320,000
Income before net gain on the sale of property									0	3,658,000	6,549,000
Net (loss)/gain on the sale of depreciable property									0	41,518,000	51,094,000
Income/(loss) from discontinued operations					42,407,000		882,000	905,000	0	45,176,000	57,643,000			982,000
Operating Community [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Property Plant Equipment									142,500,000
Discontinued Operations (Textual) [Abstract]
Number of communities sold									1
Operating Community [Member] | United Dominion Reality L.P.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Property Plant Equipment									62,500,000
Land
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Property Plant Equipment									1,100,000
Land | United Dominion Reality L.P.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Property Plant Equipment									$1,100,000

Debt_UNITED_DOMINION_REALTY_LP2

Debt (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
		Communities
Debt Instrument [Line Items]
Weighted Average Interest Rate	3.94%
Weighted Average Years to Maturity		4 years 3 months 18 days
Fixed Rate Debt
Debt Instrument [Line Items]
Principal outstanding	$969,296	$969,296	$1,072,373
Weighted Average Interest Rate	5.26%
Weighted Average Years to Maturity		3 years 0 months 2 days
Number of Communities Encumbered		28
Fixed Rate Debt | Mortgage notes payable
Debt Instrument [Line Items]
Principal outstanding			445,706
Weighted Average Interest Rate	5.46%
Weighted Average Years to Maturity		1 year 7 months 20 days
Number of Communities Encumbered	6
Fixed Rate Debt | Fannie Mae credit facilities
Debt Instrument [Line Items]
Principal outstanding			626,667
Weighted Average Years to Maturity		4 years 0 months 10 days
Number of Communities Encumbered	22
Variable Rate Debt
Debt Instrument [Line Items]
Principal outstanding	392,233	392,233	369,704
Weighted Average Interest Rate	1.44%
Weighted Average Years to Maturity		5 years 8 months 7 days
Number of Communities Encumbered		10
Variable Rate Debt | Mortgage notes payable
Debt Instrument [Line Items]
Principal outstanding			63,595
Weighted Average Interest Rate	1.94%
Weighted Average Years to Maturity		2 years 0 months 25 days
Number of Communities Encumbered	1
Variable Rate Debt | Tax-exempt secured notes payable
Debt Instrument [Line Items]
Principal outstanding			94,700
Weighted Average Interest Rate	0.83%
Weighted Average Years to Maturity		8 years 2 months 8 days
Number of Communities Encumbered	2
Variable Rate Debt | Fannie Mae credit facilities
Debt Instrument [Line Items]
Principal outstanding			211,409
Weighted Average Years to Maturity		5 years 2 months 8 days
Number of Communities Encumbered	7
United Dominion Reality L.P.
Debt Instrument [Line Items]
Principal outstanding	931,959	931,959	934,865
Weighted Average Interest Rate		4.38%
Weighted Average Years to Maturity		4 years 0 months 7 days
Number of Communities Encumbered		21
United Dominion Reality L.P. | Fannie Mae credit facilities
Debt Instrument [Line Items]
Principal outstanding	526,600	526,600
United Dominion Reality L.P. | Fixed Rate Debt
Debt Instrument [Line Items]
Principal outstanding	712,199	712,199	765,806
Weighted Average Interest Rate		5.20%
Weighted Average Years to Maturity		3 years 0 months 2 days
Number of Communities Encumbered		15
United Dominion Reality L.P. | Fixed Rate Debt | Mortgage notes payable
Debt Instrument [Line Items]
Principal outstanding	378,371	378,371	386,803
Weighted Average Interest Rate		5.47%
Weighted Average Years to Maturity		1 year 7 months 2 days
Number of Communities Encumbered		5
United Dominion Reality L.P. | Fixed Rate Debt | Fannie Mae credit facilities
Debt Instrument [Line Items]
Weighted Average Interest Rate		4.90%
Weighted Average Years to Maturity		4 years 6 months 25 days
Number of Communities Encumbered		10
United Dominion Reality L.P. | Variable Rate Debt
Debt Instrument [Line Items]
Principal outstanding	219,760	219,760	169,059
Weighted Average Interest Rate		1.72%
Weighted Average Years to Maturity		7 years 4 months 15 days
Number of Communities Encumbered		6
United Dominion Reality L.P. | Variable Rate Debt | Mortgage notes payable
Debt Instrument [Line Items]
Weighted Average Years to Maturity		0 years
United Dominion Reality L.P. | Variable Rate Debt | Tax-exempt secured notes payable
Debt Instrument [Line Items]
Principal outstanding	$27,000	$27,000	$27,000
Weighted Average Interest Rate		0.93%
Weighted Average Years to Maturity		17 years 2 months 19 days
Number of Communities Encumbered		1
United Dominion Reality L.P. | Variable Rate Debt | Fannie Mae credit facilities
Debt Instrument [Line Items]
Weighted Average Interest Rate		1.83%
Weighted Average Years to Maturity		5 years 11 months 26 days
Number of Communities Encumbered		5

Debt_UNITED_DOMINION_REALTY_LP3

Debt (UNITED DOMINION REALTY, L.P.) (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2013
Debt Instrument [Line Items]
Borrowings outstanding	$1,900		$2,200
Fannie Mae
Debt Instrument [Line Items]
Borrowings outstanding	834,282		838,076
Weighted average daily borrowings during the period ended	835,873	839,597
Maximum daily borrowings during the period ended	837,564	841,494
Weighted average interest rate during the period ended	4.10%	4.20%
Interest rate at the end of the period	4.00%		4.10%
United Dominion Reality L.P. | Fannie Mae
Debt Instrument [Line Items]
Borrowings outstanding	526,588		521,062
Weighted average daily borrowings during the period ended	527,592	522,007
Maximum daily borrowings during the period ended	$528,659	$523,187
Weighted average interest rate during the period ended		4.20%
Interest rate at the end of the period			4.10%

Debt_UNITED_DOMINION_REALTY_LP4

Debt (UNITED DOMINION REALTY, L.P.) (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
2013	$520,934
2014	248,881
2015	395,274
2016	874,199
2017	316,438
Thereafter	1,227,379
Total	1,361,529	1,442,077
United Dominion Reality L.P.
Debt Instrument [Line Items]
2013	193,003
2014	131,336
2015	23,119
2016	208,994
2017	175,998
Thereafter	199,509
Total	931,959	934,865
United Dominion Reality L.P. | Mortgage notes payable | Fixed Rate Debt
Debt Instrument [Line Items]
2013	192,637
2014	130,951
2015	913
2016	968
2017	52,902
Thereafter	0
Total	378,371
United Dominion Reality L.P. | Fannie Mae credit facilities | Fixed Rate Debt
Debt Instrument [Line Items]
2013	366
2014	385
2015	15,640
2016	111,052
2017	123,096
Thereafter	83,289
Total	333,828
United Dominion Reality L.P. | Fannie Mae credit facilities | Variable Rate Debt
Debt Instrument [Line Items]
2013	0
2014	0
2015	6,566
2016	96,974
2017	0
Thereafter	89,220
Total	192,760
United Dominion Reality L.P. | Tax-exempt secured notes payable | Variable Rate Debt
Debt Instrument [Line Items]
2013	0
2014	0
2015	0
2016	0
2017	0
Thereafter	27,000
Total	$27,000

Debt_UNITED_DOMINION_REALTY_LP5

Debt (UNITED DOMINION REALTY, L.P.) (Details Textual) (USD $)	3 Months Ended	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 26, 2013
Debt Instrument [Line Items]
Borrowings outstanding	$1,900,000	$1,900,000	$2,200,000
Debt Instrument, Interest Rate During Period	3.94%
Reallocation of Credit Facilities Debt from General Partner		0	13,682,000	0
UDR Bank Credit Facility
Debt Instrument [Line Items]
Total revolving credit facility	900,000,000	900,000,000	900,000,000
Borrowings outstanding	152,500,000	152,500,000	0
Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	969,296,000	969,296,000	1,072,373,000
Debt Instrument, Interest Rate During Period	5.26%
Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	392,233,000	392,233,000	369,704,000
Debt Instrument, Interest Rate During Period	1.44%
Fannie Mae credit facilities | Fixed Rate Debt
Debt Instrument [Line Items]
Total revolving credit facility	834,300,000	834,300,000
Secured Debt Including Debt on Real Estate Held for Sale			626,667,000
Debt, Weighted Average Interest Rate	5.12%	5.12%
Debt Instrument, Maturity Date Range, Start		1-May-17
Debt Instrument, Maturity Date Range, End		1-Jul-23
Fannie Mae credit facilities | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale			211,409,000
Debt Instrument, Interest Rate at Period End	1.60%	1.60%
Mortgages [Member] | Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale			445,706,000
Debt Instrument, Interest Rate During Period	5.46%
Debt Instrument, Maturity Date Range, Start		9-Dec-15
Debt Instrument, Maturity Date Range, End		1-May-19
Notes payable minimum interest rates range		3.43%
Notes payable maximum interest rates range		5.94%
Mortgages [Member] | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale			63,595,000
Debt Instrument, Interest Rate During Period	1.94%
Tax-exempt secured notes payable | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale			94,700,000
Debt Instrument, Interest Rate During Period	0.83%
Unsecured Revolving Credit Facility due October 2015
Debt Instrument [Line Items]
Borrowings outstanding	152,500,000	152,500,000	0
Debt Instrument, Interest Rate During Period	1.09%
2.90% Term Notes due January 2016
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period	2.17%
Five Point Two Five Percent, Medium Term Notes, Due January 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period	5.25%
4.25% Medium-Term Notes due June 2018
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period	4.25%
ThreePointSevenTermNotesDueOctober2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			300,000,000
Debt Instrument, Maturity Date					31-Oct-20
4.63% Medium-Term Notes due January 2022
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period	4.63%
3.75 MTN Due July 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period	3.75%
United Dominion Reality L.P.
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	931,959,000	931,959,000	934,865,000
Debt Instrument, Interest Rate During Period		4.38%
Unamortized fair market adjustment	6,200,000	6,200,000	10,000,000
United Dominion Reality L.P. | UDR Bank Credit Facility | Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity	900,000,000	900,000,000
United Dominion Reality L.P. | Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	712,199,000	712,199,000	765,806,000
Debt Instrument, Interest Rate During Period		5.20%
United Dominion Reality L.P. | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	219,760,000	219,760,000	169,059,000
Debt Instrument, Interest Rate During Period		1.72%
United Dominion Reality L.P. | Fannie Mae credit facilities
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	526,600,000	526,600,000
United Dominion Reality L.P. | Fannie Mae credit facilities | Fixed Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period		4.90%
United Dominion Reality L.P. | Fannie Mae credit facilities | Variable Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period		1.83%
United Dominion Reality L.P. | Mortgages [Member] | Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	378,371,000	378,371,000	386,803,000
Debt Instrument, Interest Rate During Period		5.47%
Debt Instrument, Maturity Date Range, Start		31-Dec-15
Debt Instrument, Maturity Date Range, End		1-May-19
Notes payable minimum interest rates range		3.43%
Notes payable maximum interest rates range		5.94%
United Dominion Reality L.P. | Tax-exempt secured notes payable | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	27,000,000	27,000,000	27,000,000
Debt Instrument, Interest Rate During Period		0.93%
Debt Instrument, Maturity Date Range, End		20-Mar-32
United Dominion Reality L.P. | 2.90% Term Notes due January 2016
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End		6-Jun-18
United Dominion Reality L.P. | 2.90% Term Notes due January 2016 | Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity	250,000,000	250,000,000
United Dominion Reality L.P. | 1.68% Term Notes due December 2016 | Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity	100,000,000	100,000,000
United Dominion Reality L.P. | Five Point Two Five Percent, Medium Term Notes, Due January 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End		6-Jun-18
United Dominion Reality L.P. | 4.25% Medium-Term Notes due June 2018
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End		1-Jun-18
United Dominion Reality L.P. | 4.25% Medium-Term Notes due June 2018 | Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity	300,000,000	300,000,000
United Dominion Reality L.P. | 4.63% Medium-Term Notes due January 2022
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End		1-Jan-22
United Dominion Reality L.P. | 4.63% Medium-Term Notes due January 2022 | Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity	400,000,000	400,000,000
United Dominion Reality L.P. | 3.75 MTN Due July 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End		31-Jul-24
United Dominion Reality L.P. | 3.75 MTN Due July 2024 [Member] | Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity	300,000,000	300,000,000
Beginning of range of initial term of debt [Member] | Fannie Mae credit facilities
Debt Instrument [Line Items]
Debt Instrument, Term		7 years
End of range of inital term of debt [Member] | Fannie Mae credit facilities
Debt Instrument [Line Items]
Debt Instrument, Term		10 years
Line of Credit [Member] | Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Fannie Mae credit facilities | Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	568,086,000	568,086,000
Line of Credit [Member] | Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Fannie Mae credit facilities | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	266,196,000	266,196,000
Line of Credit [Member] | Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | United Dominion Reality L.P. | Fannie Mae credit facilities | Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	333,828,000	333,828,000	379,003,000
Line of Credit [Member] | Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | United Dominion Reality L.P. | Fannie Mae credit facilities | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	192,760,000	192,760,000	142,059,000
Mortgages [Member] | Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	401,210,000	401,210,000
Mortgages [Member] | Reported Value Measurement [Member] | Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale	$31,337,000	$31,337,000

Related_Party_Transactions_UNI1

Related Party Transactions (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2014
Related Party Transaction [Line Items]
Related party management fees	$12,700,000	$12,300,000	$11,900,000
Limited Partners' Capital Account, Units Redeemed		1,002,556
United Dominion Reality L.P.
Related Party Transaction [Line Items]
Net receivable balances from General Partner	-13,624,000	9,916,000
Related party management fee percentage	2.75%
Notes payable due to General Partner	88,696,000	88,696,000
OP Units issued for real estate	77,041,000		0
United Dominion Reality L.P. | Taxable REIT Subsidiaries
Related Party Transaction [Line Items]
Net receivable balances from General Partner	13,624,000	-9,916,000
Related party management fee percentage	2.75%
United Dominion Reality L.P. | UDR, Inc.
Related Party Transaction [Line Items]
General and administrative expenses allocated to the Operating Partnership by UDR	27,400,000	23,500,000	25,200,000
United Dominion Reality L.P. | UDR, Inc. | Bottom Dollar guaranty
Related Party Transaction [Line Items]
Related party guaranty note payable interest rate	5.18%	5.18%		5.18%
Notes payable due to General Partner	83,200,000	83,300,000
United Dominion Reality L.P. | UDR, Inc. | Guaranty related to community acquisition
Related Party Transaction [Line Items]
Related party guaranty note payable interest rate	5.34%
Notes payable due to General Partner	5,500,000	5,500,000
Number of OP Units issued as consideration for acquisition guaranteed by related party note payable (in shares)			1,802,239
Receivable Due From General Partner [Member] | United Dominion Reality L.P.
Related Party Transaction [Line Items]
OP Units issued for real estate	$53,712,000

Fair_Value_of_Derivatives_and_5

Fair Value of Derivatives and Financial Instruments (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$88		$0
Derivatives - Interest rate contracts	10,368		4,965
Fair Value | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	14,896		83,833
Secured debt instruments - variable rate
Total liabilities	3,721,512		3,651,141
Fair Value | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	88
Derivatives - Interest rate contracts	10,368	[1]	4,965	[2]
Fair Value | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	415,663	[2]	466,375	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate	31,337	[2]	63,595	[3]
Fair Value | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	94,700	[2]	94,700	[3]
Fair Value | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	606,623	[2]	661,094	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate	266,196	[2]	211,409	[3]
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	0		0
Secured debt instruments - variable rate
Total liabilities	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0
Derivatives - Interest rate contracts	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	88		0
Secured debt instruments - variable rate
Total liabilities	10,368		4,965
Fair Value | Significant Other Observable Inputs (Level 2) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	88
Derivatives - Interest rate contracts	10,368
Fair Value | Significant Other Observable Inputs (Level 2) | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Other Observable Inputs (Level 2) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
Fair Value | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	14,808		83,833
Secured debt instruments - variable rate
Total liabilities	3,711,144		3,646,176
Fair Value | Significant Unobservable Inputs (Level 3) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0
Derivatives - Interest rate contracts	0		0
Fair Value | Significant Unobservable Inputs (Level 3) | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	415,663		466,375
Secured debt instruments - variable rate
Secured debt instruments - variable rate	31,337		63,595
Fair Value | Significant Unobservable Inputs (Level 3) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	94,700		94,700
Fair Value | Significant Unobservable Inputs (Level 3) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	606,623		661,094
Secured debt instruments - variable rate
Secured debt instruments - variable rate	266,196		211,409
Carrying Amount | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	14,457		83,033
Secured debt instruments - variable rate
Total liabilities	3,593,473		3,528,668
Carrying Amount | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivatives - Interest rate contracts			4,965	[2]
Carrying Amount | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate			445,706	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate			63,595	[3]
Carrying Amount | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate			94,700	[3]
Carrying Amount | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate			626,667	[3]
Secured debt instruments - variable rate
Secured debt instruments - variable rate			211,409	[3]
United Dominion Reality L.P.
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	39		0
Derivatives - Interest rate contracts	918		2,731
United Dominion Reality L.P. | Fair Value | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	39
Secured debt instruments - variable rate
Total liabilities	967,983		969,724
United Dominion Reality L.P. | Fair Value | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	39	[4]
Derivatives - Interest rate contracts	918	[4]	2,731	[4]
United Dominion Reality L.P. | Fair Value | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	391,835	[5]	403,695	[5]
United Dominion Reality L.P. | Fair Value | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	27,000	[5]	27,000	[5]
United Dominion Reality L.P. | Fair Value | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	355,470	[5]	394,239	[5]
Secured debt instruments - variable rate
Secured debt instruments - variable rate	192,760	[5]	142,059	[5]
United Dominion Reality L.P. | Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	0
Secured debt instruments - variable rate
Total liabilities	0		0
United Dominion Reality L.P. | Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0
Derivatives - Interest rate contracts	0		0
United Dominion Reality L.P. | Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
United Dominion Reality L.P. | Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
United Dominion Reality L.P. | Fair Value | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
United Dominion Reality L.P. | Fair Value | Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	39
Secured debt instruments - variable rate
Total liabilities	918		2,731
United Dominion Reality L.P. | Fair Value | Significant Other Observable Inputs (Level 2) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	39
Derivatives - Interest rate contracts	918		2,731
United Dominion Reality L.P. | Fair Value | Significant Other Observable Inputs (Level 2) | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
United Dominion Reality L.P. | Fair Value | Significant Other Observable Inputs (Level 2) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
United Dominion Reality L.P. | Fair Value | Significant Other Observable Inputs (Level 2) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	0		0
Secured debt instruments - variable rate
Secured debt instruments - variable rate	0		0
United Dominion Reality L.P. | Fair Value | Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	0
Secured debt instruments - variable rate
Total liabilities	967,065		966,993
United Dominion Reality L.P. | Fair Value | Significant Unobservable Inputs (Level 3) | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0
Derivatives - Interest rate contracts	0		0
United Dominion Reality L.P. | Fair Value | Significant Unobservable Inputs (Level 3) | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	391,835		403,695
United Dominion Reality L.P. | Fair Value | Significant Unobservable Inputs (Level 3) | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	27,000		27,000
United Dominion Reality L.P. | Fair Value | Significant Unobservable Inputs (Level 3) | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	355,470		394,239
Secured debt instruments - variable rate
Secured debt instruments - variable rate	192,760		142,059
United Dominion Reality L.P. | Carrying Amount | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Total assets	39
Secured debt instruments - variable rate
Total liabilities	932,877		937,596
United Dominion Reality L.P. | Carrying Amount | Interest rate contracts | Fair Value, Measurements, Recurring
Estimated fair values of the financial instruments either recorded or disclosed on a recurring basis
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	39	[4]
Derivatives - Interest rate contracts	918	[4]	2,731	[4]
United Dominion Reality L.P. | Carrying Amount | Mortgage notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	378,371	[5]	386,803	[5]
United Dominion Reality L.P. | Carrying Amount | Tax-exempt secured notes payable | Fair Value, Measurements, Recurring
Secured debt instruments - variable rate
Secured debt instruments - variable rate	27,000	[5]	27,000	[5]
United Dominion Reality L.P. | Carrying Amount | Fannie Mae credit facilities | Fair Value, Measurements, Recurring
Secured debt instruments - fixed rate
Secured debt instruments - fixed rate	333,828	[5]	379,003	[5]
Secured debt instruments - variable rate
Secured debt instruments - variable rate	$192,760	[5]	$142,059	[5]
[1]	See Note 6, Secured Debt and Unsecured Debt.
[2]	See Note 2, Significant Accounting Policies.
[3]	See Note 13, Derivatives and Hedging Activity.
[4]	See Note 8, Derivatives and Hedging Activity
[5]	See Note 5, Debt

Derivatives_and_Hedging_Activi9

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified	instruments
Designated as Hedging Instrument | Interest rate swaps
Derivative [Line Items]
Number of Instruments	14
Derivative, Notional Amount	$365,000
Designated as Hedging Instrument | Interest rate caps
Derivative [Line Items]
Number of Instruments	3
Derivative, Notional Amount	243,079
Not Designated as Hedging Instrument | Interest rate caps
Derivative [Line Items]
Number of Instruments	1
Derivative, Notional Amount	96,409
United Dominion Reality L.P. | Designated as Hedging Instrument | Interest rate swaps
Derivative [Line Items]
Number of Instruments	1
Derivative, Notional Amount	46,272
United Dominion Reality L.P. | Designated as Hedging Instrument | Interest rate caps
Derivative [Line Items]
Number of Instruments	2
Derivative, Notional Amount	166,341
United Dominion Reality L.P. | Not Designated as Hedging Instrument | Interest rate caps
Derivative [Line Items]
Number of Instruments	1
Derivative, Notional Amount	$89,220

Recovered_Sheet1

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Asset Designated as Hedging Instrument, Fair Value	$88	$0
Derivative Liability Designated as Hedging Instrument, Fair Value	10,368	4,965
Interest rate products | Other assets | Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Asset Designated as Hedging Instrument, Fair Value	86	0
Interest rate products | Other assets | Not Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Asset Not Designated as Hedging Instrument, Fair Value	2	0
Interest rate products | Other liabilities | Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Liability Designated as Hedging Instrument, Fair Value	10,368	4,965
Interest rate products | Other liabilities | Not Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Liability Not Designated as Hedging Instrument, Fair Value	0	0
United Dominion Reality L.P.
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Asset Designated as Hedging Instrument, Fair Value	39	0
Derivative Liability Designated as Hedging Instrument, Fair Value	918	2,731
United Dominion Reality L.P. | Interest rate products | Other assets | Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Asset Designated as Hedging Instrument, Fair Value	37	0
United Dominion Reality L.P. | Interest rate products | Other assets | Not Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Asset Not Designated as Hedging Instrument, Fair Value	2	0
United Dominion Reality L.P. | Interest rate products | Other liabilities | Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Liability Designated as Hedging Instrument, Fair Value	918	2,731
United Dominion Reality L.P. | Interest rate products | Other liabilities | Not Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Derivative Liability Not Designated as Hedging Instrument, Fair Value	$0	$0

Recovered_Sheet2

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total	$4,834,000	$6,851,000	$7,649,000
Interest rate products | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net, Total	-8,695,000	-469,000	-4,924,000
Interest rate products | Other Income Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net, Total	-4,000	271,000	290,000
Interest rate products | Interest expense | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total	4,834,000	6,851,000	7,649,000
United Dominion Reality L.P.
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total	2,275,000	2,652,000	3,431,000
United Dominion Reality L.P. | Interest rate products | Other Income Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net, Total	-3,000	-9,000	-9,000
United Dominion Reality L.P. | Interest rate products | Interest expense | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net, Total	-285,000	-348,000	-1,898,000
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total	($2,275,000)	($2,652,000)	($3,431,000)

Recovered_Sheet3

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]
Derivative, Collateral, Obligation to Return Securities	($27)	$0
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	61	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	88	0
Derivative Asset, Not Subject to Master Netting Arrangement	0	0
Derivative Asset	88	0
United Dominion Reality L P [Member]
Derivative [Line Items]
Derivative, Collateral, Obligation to Return Securities	0	0
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	39	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	39	0
Derivative Asset, Not Subject to Master Netting Arrangement	0	0
Derivative Asset	$39	$0

Recovered_Sheet4

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]
Derivative Liability		$4,965
Derivative, Collateral, Right to Reclaim Securities	-27	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	10,341	4,965
Derivative Liability Designated as Hedging Instrument, Fair Value	10,368	4,965
Derivative Liability, Not Subject to Master Netting Arrangement	0	0
Derivative, Collateral, Right to Reclaim Cash	0	0
United Dominion Reality L P [Member]
Derivative [Line Items]
Derivative Liability	918	2,731
Derivative, Collateral, Right to Reclaim Securities	0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	918	2,731
Derivative Liability Designated as Hedging Instrument, Fair Value	918	2,731
Derivative Liability, Not Subject to Master Netting Arrangement	0	0
Derivative, Collateral, Right to Reclaim Cash	$0	$0

Recovered_Sheet5

Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Entity Information [Line Items]
Derivative, Collateral, Obligation to Return Cash	$0	$0
Cash flow hedge ineffectiveness in earnings materiality	3000	less than $1,000	less than a B $1,000
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	5,000,000
Fair value of derivatives in a net liability position	10,600,000
Payment required to pay for contract termination	10,600,000
Maximum
Entity Information [Line Items]
Cash flow hedge ineffectiveness in earnings		1,000	1,000
United Dominion Reality L.P.
Entity Information [Line Items]
Derivative, Collateral, Obligation to Return Cash	0	0
Cash flow hedge ineffectiveness in earnings materiality	less than $1,000
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	900,000
Fair value of derivatives in a net liability position	1,000,000
Payment required to pay for contract termination	1,000,000
Interest rate contracts | Other Income Expense [Member]
Entity Information [Line Items]
Losses in the fair value of derivatives not designated in hedging relationships	4,000	-271,000	-290,000
Interest rate contracts | Other Income Expense [Member] | United Dominion Reality L.P.
Entity Information [Line Items]
Losses in the fair value of derivatives not designated in hedging relationships	$3,000	$9,000	9,000

Capital_Structure_UNITED_DOMIN2

Capital Structure (UNITED DOMINION REALTY, L.P.) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, Units Redeemed		-1,002,556
Partners' Capital Account, Units, Acquisitions		-1,002,556
Balance	183,278,698	184,281,254	184,281,254
Partners' Capital Account, Units, Redeemed	0	0	0
OP Units issued for acquisitions of real estate			0
Balance	183,278,698	183,278,698	184,281,254
UDR, Inc.
Limited Partners' Capital Account [Line Items]
Balance	174,002,342	173,848,891
Class A Limited Partner
Limited Partners' Capital Account [Line Items]
Balance	1,751,671
Limited Partner
Limited Partners' Capital Account [Line Items]
Partners' Capital Account, Units, Acquisitions		0
Balance	7,567,253	7,643,548	7,669,632
Partners' Capital Account, Units, Redeemed	-153,451	-76,295	-20,438
OP Units issued for acquisitions of real estate			-5,646
Balance	7,413,802	7,567,253	7,643,548
Limited Partner | UDR, Inc.
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, Units Redeemed		1,002,556
Partners' Capital Account, Units, Acquisitions		-1,002,556
Balance	173,848,891	174,775,152	174,749,068
Partners' Capital Account, Units, Redeemed	153,451	76,295	20,438
OP Units issued for acquisitions of real estate			5,646
Balance	174,002,342	173,848,891	174,775,152
Limited Partner | Class A Limited Partner
Limited Partners' Capital Account [Line Items]
Partners' Capital Account, Units, Acquisitions		0
Balance	1,751,671	1,751,671	1,751,671
Partners' Capital Account, Units, Redeemed	0	0	0
OP Units issued for acquisitions of real estate			0
Balance	1,751,671	1,751,671	1,751,671
General Partner | UDR, Inc.
Limited Partners' Capital Account [Line Items]
Partners' Capital Account, Units, Acquisitions		0
Balance	110,883	110,883	110,883
Partners' Capital Account, Units, Redeemed	0	0	0
OP Units issued for acquisitions of real estate			0
Balance	110,883	110,883	110,883

Capital_Structure_UNITED_DOMIN3

Capital Structure (UNITED DOMINION REALTY, L.P.) (Details Textual) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, Units Redeemed	-1,002,556
Limited partnership units owned	183,278,698	183,278,698	184,281,254	184,281,254
Redeemable non-controlling interests in operating partnership	$217,597	$282,480
United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
General Partners' Capital Account, Units Outstanding	110,883	110,883
Limited partnership units owned	183,167,815	183,167,815
Required period to be outstanding before unit is redeemable		1 year
Redeemable non-controlling interests in operating partnership	217,597	282,480
OP Units issued for real estate		77,041	0
UDR, Inc.
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	173,848,891	174,002,342
Percentage of units	94.90%	95.00%
Non-affiliated Partners
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	9,318,924	9,165,473
Percentage of units	5.10%	5.00%
Class A Limited Partner
Limited Partners' Capital Account [Line Items]
Limited partnership units owned		1,751,671
Cumulative, annual, non-compounded preferred return on Class A Partnership units		8.00%
Value of Class A Partnership units (in dollars per share)		$16.61
Class A Limited Partner | United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	1,751,671	1,873,332
Limited Partner
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	7,567,253	7,413,802	7,643,548	7,669,632
Limited Partner | United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
OP Units issued for real estate			-133
Limited Partner | UDR, Inc.
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, Units Redeemed	1,002,556
Limited partnership units owned	173,848,891	174,002,342	174,775,152	174,749,068
Limited Partner | Class A Limited Partner
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	1,751,671	1,751,671	1,751,671	1,751,671
Partnership Capital [Member] | United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
OP Units issued for real estate	$23,329		$0

Commitments_and_Contingencies_6

Commitments and Contingencies (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
	Communities
Real Estate Properties [Line Items]
Costs Incurred to Date	$549,130,000
Expected Costs to Complete	255,747,000	[1]
Ground Leases
Real Estate Properties [Line Items]
Number of Real Estate Properties	6
2013	5,412,000	[2]
2014	5,412,000	[2]
2015	5,412,000	[2]
2016	5,412,000	[2]
2017	5,412,000	[2]
Thereafter	313,735,000	[2]
Rent expense	5,400,000		5,200,000	5,100,000
United Dominion Reality L.P.
Real Estate Properties [Line Items]
Capital Expenditures Incurred but Not yet Paid	7,254,000		6,371,000	7,440,000
Number of Real Estate Properties	68
United Dominion Reality L.P. | Ground Leases
Real Estate Properties [Line Items]
Number of Real Estate Properties	5
2013	5,300,000
2014	5,200,000
2015	5,200,000
2016	5,200,000
2017	5,200,000
Thereafter	313,600,000	[2]
Rent expense	5,300,000		5,100,000	5,000,000
Wholly-owned b under development
Real Estate Properties [Line Items]
Capital Expenditures Incurred but Not yet Paid	14,700,000
Number of Real Estate Properties	1
Costs Incurred to Date	177,632,000
Wholly-owned b redevelopment
Real Estate Properties [Line Items]
Capital Expenditures Incurred but Not yet Paid	1,800,000
Number of Real Estate Properties	1
Costs Incurred to Date	$83,778,000
[1]	Represents 100% of project costs incurred to date.
[2]	For purposes of our ground lease contracts, the Company uses the minimum lease payment, if stated in the agreement. For ground lease agreements where there is a reset provision based on the communities appraised value or consumer price index but does not include a specified minimum lease payment, the Company uses the current rent over the remainder of the lease term.

Reportable_Segments_UNITED_DOM2

Reportable Segments (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	12 Months Ended			3 Months Ended							9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2011	Dec. 31, 2009
	Segments
Reportable Segment (Textual) [Abstract]
Number of reportable segments	2
Condition for Community considered to have stabilized occupancy	90% occupancy for at least three consecutive months
Number of tenants or related group of tenants that contributed 10% or more of company total revenue	0	0	0
Reportable apartment home segment rental income	$818,046,000	$758,926,000	$716,612,000
Reportable apartment home segment NOI	556,321,000	514,041,000	504,200,000
Reconciling items:
Property management	-22,142,000	-20,780,000	-20,465,000
Other operating expenses	-8,271,000	-7,136,000	-5,718,000
Depreciation and amortization	-358,154,000	-341,490,000	-350,401,000
General and administrative	-47,800,000	-42,238,000	-43,792,000
Casualty-related (recoveries)/charges, net	-541,000	12,253,000	-8,495,000
Non-controlling interests	3,000	60,000	-140,000
Net income/(loss) attributable to Entity	154,334,000	44,812,000	212,177,000
Reportable apartment home segment assets:
Total segment assets	8,383,259,000	8,207,977,000		8,383,259,000				8,207,977,000
Accumulated depreciation	-2,434,772,000	-2,208,794,000		-2,434,772,000				-2,208,794,000
Total real estate owned, net of accumulated depreciation	5,948,487,000	5,999,183,000		5,948,487,000				5,999,183,000
Reconciling items:
Cash and cash equivalents	15,224,000	30,249,000	12,115,000	15,224,000				30,249,000				12,503,000
Restricted cash	22,340,000	22,796,000		22,340,000				22,796,000
Deferred financing costs, net	22,686,000	26,924,000		22,686,000				26,924,000
Other assets	105,202,000	137,882,000		105,202,000				137,882,000
Total assets	6,846,534,000	6,807,722,000		6,846,534,000				6,807,722,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	326,461,000	452,057,000	422,480,000
Same Communities
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	55,300,000	47,500,000	46,400,000
Same Communities Western Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	245,803,000	231,156,000	218,268,000
Reportable apartment home segment NOI	178,926,000	166,033,000	154,205,000
Reportable apartment home segment assets:
Total segment assets	2,358,444,000	2,337,980,000		2,358,444,000				2,337,980,000
Same Communities Mid-Atlantic Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	161,566,000	160,208,000	155,777,000
Reportable apartment home segment NOI	111,762,000	111,643,000	108,490,000
Reportable apartment home segment assets:
Total segment assets	1,410,156,000	1,395,772,000		1,410,156,000				1,395,772,000
Same Communities Northeast Region [Member]
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	60,796,000	58,075,000	54,461,000
Reportable apartment home segment NOI	44,897,000	42,350,000	39,377,000
Reportable apartment home segment assets:
Total segment assets	746,550,000	738,805,000		746,550,000				738,805,000
Same Communities Southeastern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	107,991,000	102,988,000	97,699,000
Reportable apartment home segment NOI	71,528,000	67,264,000	63,122,000
Reportable apartment home segment assets:
Total segment assets	786,438,000	785,134,000		786,438,000				785,134,000
Same Communities Southwestern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	54,810,000	52,302,000	46,800,000
Reportable apartment home segment NOI	33,725,000	31,927,000	27,878,000
Reportable apartment home segment assets:
Total segment assets	440,721,000	434,875,000		440,721,000				434,875,000
Non-Mature communities/Other
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	174,183,000	150,907,000	171,239,000
Reportable apartment home segment NOI	115,483,000	94,824,000	111,128,000
Reportable apartment home segment assets:
Total segment assets	2,640,950,000	2,515,411,000		2,640,950,000				2,515,411,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	8,100,000	8,300,000	8,700,000
United Dominion Reality L.P.
Reportable Segment (Textual) [Abstract]
Related party management fee percentage	2.75%
Number of reportable segments	2
Condition for Community considered to have stabilized occupancy	once it achieves 90% occupancy for at least three consecutive months
Number of tenants or related group of tenants that contributed 10% or more of company total revenue	0		0
Reportable apartment home segment rental income	422,634,000	410,842,000	400,691,000
Reportable apartment home segment NOI	300,313,000	287,535,000	281,538,000
Reconciling items:
Property management	-11,622,000	-11,298,000	-11,019,000
Other operating expenses	-5,172,000	-5,728,000	-5,272,000
Depreciation and amortization	-179,176,000	-181,302,000	-195,051,000
Interest	-41,717,000	-36,058,000	-45,234,000
General and administrative	-28,541,000	-24,808,000	-26,204,000
Casualty-related (recoveries)/charges, net	-541,000	8,083,000	-5,518,000
Net gain on sale of depreciable property	63,635,000	41,518,000	51,094,000
Non-controlling interests	-952,000	-4,566,000	-352,000
Net income/(loss) attributable to Entity	96,227,000	73,376,000	43,982,000	32,631,000	8,637,000	24,426,000	30,533,000	44,482,000	10,154,000	7,729,000	11,011,000
Reportable apartment home segment assets:
Total segment assets	4,238,770,000	4,188,480,000		4,238,770,000				4,188,480,000
Accumulated depreciation	-1,403,303,000	-1,241,574,000		-1,403,303,000				-1,241,574,000
Total real estate owned, net of accumulated depreciation	2,835,467,000	2,946,906,000		2,835,467,000				2,946,906,000
Reconciling items:
Cash and cash equivalents	502,000	1,897,000	2,804,000	502,000				1,897,000					704,000
Restricted cash	13,811,000	13,526,000		13,811,000				13,526,000
Deferred financing costs, net	4,475,000	5,848,000		4,475,000				5,848,000
Other assets	24,029,000	25,064,000		24,029,000				25,064,000
Total assets	2,878,284,000	2,993,241,000		2,878,284,000				2,993,241,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	91,682,000	151,002,000	115,355,000
United Dominion Reality L.P. | Same Communities
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	32,800,000	25,800,000
United Dominion Reality L.P. | Same Communities Western Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	194,105,000	181,935,000	172,096,000
Reportable apartment home segment NOI	142,388,000	131,276,000	122,477,000
Reportable apartment home segment assets:
Total segment assets	1,749,494,000	1,733,144,000		1,749,494,000				1,733,144,000
United Dominion Reality L.P. | Same Communities Mid-Atlantic Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	68,822,000	68,205,000	66,487,000
Reportable apartment home segment NOI	46,639,000	46,770,000	45,801,000
Reportable apartment home segment assets:
Total segment assets	713,093,000	706,447,000		713,093,000				706,447,000
United Dominion Reality L.P. | Same Communities Northeast Region [Member]
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	38,087,000	36,623,000	34,579,000
Reportable apartment home segment NOI	28,930,000	27,149,000	25,653,000
Reportable apartment home segment assets:
Total segment assets	447,269,000	443,483,000		447,269,000				443,483,000
United Dominion Reality L.P. | Same Communities Southeastern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	45,224,000	43,208,000	40,771,000
Reportable apartment home segment NOI	29,815,000	28,105,000	26,510,000
Reportable apartment home segment assets:
Total segment assets	333,428,000	328,150,000		333,428,000				328,150,000
United Dominion Reality L.P. | Same Communities Southwestern Region
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	26,580,000	25,614,000	23,980,000
Reportable apartment home segment NOI	16,821,000	16,057,000	14,738,000
Reportable apartment home segment assets:
Total segment assets	228,996,000	226,252,000		228,996,000				226,252,000
United Dominion Reality L.P. | Non-Mature communities/Other
Reportable Segment (Textual) [Abstract]
Reportable apartment home segment rental income	49,816,000	55,257,000	62,778,000
Reportable apartment home segment NOI	35,720,000	38,178,000	46,359,000
Reportable apartment home segment assets:
Total segment assets	766,490,000	751,004,000		766,490,000				751,004,000
Reportable Segments Additional (Textual) [Abstract]
Capital expenditures related to segments	$1,000,000	$2,000,000
United Dominion Reality L.P. | Minimum
Reportable Segment (Textual) [Abstract]
Percent occupancy to be considered a community	90.00%
Time to maintain percent occupancy to be considered a community	3 months

Hurricane_Related_Charges_UNIT1

Hurricane Related Charges (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	12 Months Ended			4 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 30, 2013
Hurricane Related Charges [Line Items]
Other Cost and Expense, Operating	$8,271,000	$7,136,000	$5,718,000
Proceeds from Insurance Settlement, Investing Activities		2,600,000	4,200,000
Casualty-related (recoveries)/charges, net	-541,000	12,253,000	-8,495,000
Casualty-related (recoveries)/charges, net	-541,000	12,253,000	-8,495,000
Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Total Estimated Insurance Recovery			14,500,000
Casualty-related (recoveries)/charges, net		4,800,000
Other Nonrecurring Expense		3,400,000	4,400,000
Casualty Gain [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Casualty-related (recoveries)/charges, net		654,000
Rent concessions | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			3,600,000
Rent not contractually receivable | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			767,000
New York Properties [Member]
Hurricane Related Charges [Line Items]
Number of Communities Owned			3
Number of Apartments Owned			1,706
Impairment of Long-Lived Assets Held-for-use		0	9,000,000
Other Cost and Expense, Operating			10,400,000
United Dominion Reality L.P.
Hurricane Related Charges [Line Items]
Other Cost and Expense, Operating	5,172,000	5,728,000	5,272,000
Casualty-related (recoveries)/charges, net	-541,000	8,083,000	-5,518,000
United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Impairment of Long-Lived Assets Held-for-use		0	7,100,000
Other Cost and Expense, Operating			7,000,000
Total Estimated Insurance Recovery		10,800,000	10,800,000
Casualty-related (recoveries)/charges, net		3,300,000
Other Nonrecurring Expense		2,100,000	2,200,000
United Dominion Reality L.P. | Casualty Gain [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Casualty-related (recoveries)/charges, net		582,000
United Dominion Reality L.P. | Rent concessions | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			1,800,000
United Dominion Reality L.P. | Rent not contractually receivable | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Other Nonrecurring Expense			400,000
United Dominion Reality L.P. | New York Properties [Member]
Hurricane Related Charges [Line Items]
Number of Communities Owned			2
Number of Apartments Owned			1,001
Business Interruption [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		6,800,000
Business Interruption [Member] | United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		4,200,000
FY 2013 [Member] | Business Interruption [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		2,600,000
FY 2013 [Member] | Business Interruption [Member] | United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities				2,100,000
FY 2012 [Member] | Business Interruption [Member] | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		4,200,000
FY 2012 [Member] | Business Interruption [Member] | United Dominion Reality L.P. | Hurricane Sandy [Member]
Hurricane Related Charges [Line Items]
Proceeds from Insurance Settlement, Investing Activities		$2,100,000

Unaudited_Summarized_Consolida5

Unaudited Summarized Consolidated Quarterly Financial Data (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	3 Months Ended																12 Months Ended			9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013
Quarterly Financial Data [Abstract]
Rental income	$206,104	[1]	$203,587	[1]	$200,959	[1]	$194,352	[1]	$190,321	[1]	$187,917	[1]	$186,285	[1]	$181,961	[1]
Income/(loss) from continuing operations	6,485		10,611		4,359		-5,195		-3,374		2,351		4,525		-1,162		16,260	2,340	-46,305
Income/(loss) from discontinued operations	0		79		18		-87		41,376		884		829		853		10	43,942	266,608
Net income																	154,334	44,812	212,177
Net (loss)/income attributable to stakeholders	64,486		39,618		29,076		17,430		35,769		2,257		4,261		-1,199		150,610	41,088	203,376
Earnings per weighted average common share - basic and diluted:
Net (loss)/income attributable to common stockholders b basic and diluted (in dollars per share)	$0.25	[2]	$0.16	[2]	$0.12	[2]	$0.07	[2]	$0.14	[2]	$0.01	[2]	$0.02	[2]	$0	[2]
United Dominion Reality L.P.
Quarterly Financial Data [Abstract]
Rental income	107,978	[1]	107,444	[1]	104,842	[1]	102,370	[1]	102,104	[1]			100,421	[1]	97,770	[1]	422,634	401,853	384,946	101,558	[1]
Income/(loss) from continuing operations	9,939		8,875		8,319		6,411		6,488				9,339		6,870		33,544	32,766	-13,309	10,069
Income/(loss) from discontinued operations									42,407				882		905		0	45,176	57,643	982
Net income	$32,631		$8,637		$24,426		$30,533		$44,482				$10,154		$7,729		$96,227	$73,376	$43,982	$11,011
Net Income (Loss), Per Outstanding Limited Partnership and General Partnership Unit, Basic and Diluted	$0.18	[3]	$0.05	[3]	$0.13	[3]	$0.17	[3]	$0.24				$0.06		$0.04		$0.53	$0.40	$0.24	$0.06
[1]	Represents rental income from continuing operations, excluding amounts classified as discontinued operations.
[2]	Quarterly income/(loss) per share amounts may not total to the annual amounts.
[3]	Quarterly income/(loss) per OP Unit amounts may not total to the annual amounts

Schedule_III_Real_Estate_Owned2

Schedule - III Real Estate Owned (Details) (USD $)	1 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014
Real Estate and Accumulated Depreciation [Line Items]
Total Carrying Value		$8,383,259,000	$8,207,977,000	$8,055,828,000
Accumulated Depreciation		2,434,772,000	2,208,794,000	1,924,682,000
Aggregate cost for federal income tax purposes		7,700,000,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year		8,207,977,000	8,055,828,000	8,074,471,000
Real estate acquired		231,225,000	0	141,648,000
Capital expenditures and development		326,461,000	452,057,000	422,480,000
Real estate sold	-140,000,000	-269,681,000	-70,687,000	-559,154,000
Retirement of fully depreciated assets		0	0	-13,945,000
Hurricane related impairment of assets		-379,000	-2,355,000	-9,672,000
SEC Schedule III, Real Estate, Other Additions		0	0	0
Balance at end of the year		8,383,259,000	8,207,977,000	8,055,828,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year		2,208,794,000	1,924,682,000	1,831,727,000
Depreciation expense for the year		356,673,000	339,326,000	340,800,000
Accumulated depreciation on sales		-126,151,000	-34,794,000	-233,207,000
Accumulated depreciation on retirements of fully depreciated assets		0	-1,132,000	-13,945,000
SEC Schedule III, Real Estate Accumulated Depreciation, Other Additions		0	1,374,000	0
Write off of accumulated depreciation on hurricane related impaired assets		-316,000	0	-693,000
Balance at end of year		2,434,772,000	2,208,794,000	1,924,682,000
Estimated depreciable lives of buildings range beginning
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for all buildings		35 years
Estimated depreciable lives of buildings range end
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for all buildings		55 years
Total Operating Properties [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					1,361,530,000
Initial Costs, Land and Land Improvements					1,586,655,000
Initial Costs, Buildings and Improvements					4,255,392,000
Total Initial Acquisition Costs					5,842,047,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,125,393,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,788,133,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					6,179,242,000
Total Carrying Value					7,967,375,000
Accumulated Depreciation					2,415,413,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					7,967,375,000
Balance at end of the year					7,967,375,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,415,413,000
Balance at end of year					2,415,413,000
Other
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0	[1]
Initial Costs, Land and Land Improvements					0	[1]
Initial Costs, Buildings and Improvements					0	[1]
Total Initial Acquisition Costs					0	[1]
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,181,000	[1]
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					0	[1]
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					4,181,000	[1]
Total Carrying Value					4,181,000	[1]
Accumulated Depreciation					47,000	[1]
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					4,181,000	[1]
Balance at end of the year					4,181,000	[1]
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					47,000	[1]
Balance at end of year					47,000	[1]
TOTAL CORPORATE
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					0
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					0
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,181,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					0
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					4,181,000
Total Carrying Value					4,181,000
Accumulated Depreciation					47,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					4,181,000
Balance at end of the year					4,181,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					47,000
Balance at end of year					47,000
Real Estate Under Development
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					24,584,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					24,584,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					153,048,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					24,584,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					153,048,000
Total Carrying Value					177,632,000
Accumulated Depreciation					0
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					177,632,000
Balance at end of the year					177,632,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0
Balance at end of year					0
Real Estate Under Development | Pier 4
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					24,584,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					24,584,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					153,048,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					24,584,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					153,048,000
Total Carrying Value					177,632,000
Accumulated Depreciation					0
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					177,632,000
Balance at end of the year					177,632,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0
Balance at end of year					0
Land
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					144,830,000
Initial Costs, Buildings and Improvements					2,768,000
Total Initial Acquisition Costs					147,598,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					23,655,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					151,891,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					19,362,000
Total Carrying Value					171,253,000
Accumulated Depreciation					4,215,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					171,253,000
Balance at end of the year					171,253,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,215,000
Balance at end of year					4,215,000
Land | 2919 Wilshire
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,773,000
Initial Costs, Buildings and Improvements					527,000
Total Initial Acquisition Costs					7,300,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					880,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,773,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,407,000
Total Carrying Value					8,180,000
Accumulated Depreciation					527,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					8,180,000
Balance at end of the year					8,180,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					527,000
Balance at end of year					527,000
Land | 3032 Wilshire
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					9,963,000
Initial Costs, Buildings and Improvements					788,000
Total Initial Acquisition Costs					10,751,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,642,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,963,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,430,000
Total Carrying Value					12,393,000
Accumulated Depreciation					788,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,393,000
Balance at end of the year					12,393,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					788,000
Balance at end of year					788,000
Land | 7 Hardcourt
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					884,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					884,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,734,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					804,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					4,814,000
Total Carrying Value					5,618,000
Accumulated Depreciation					614,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					5,618,000
Balance at end of the year					5,618,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					614,000
Balance at end of year					614,000
Land | Waterside
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					11,862,000
Initial Costs, Buildings and Improvements					93,000
Total Initial Acquisition Costs					11,955,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					189,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					12,084,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					60,000
Total Carrying Value					12,144,000
Accumulated Depreciation					263,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,144,000
Balance at end of the year					12,144,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					263,000
Balance at end of year					263,000
Land | Vitruvian
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,325,000
Initial Costs, Buildings and Improvements					1,360,000
Total Initial Acquisition Costs					5,685,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,965,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,244,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,406,000
Total Carrying Value					13,650,000
Accumulated Depreciation					2,023,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,650,000
Balance at end of the year					13,650,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,023,000
Balance at end of year					2,023,000
Land | Pacific City [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					78,085,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					78,085,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,962,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					78,085,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					7,962,000
Total Carrying Value					86,047,000
Accumulated Depreciation					0
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					86,047,000
Balance at end of the year					86,047,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0
Balance at end of year					0
Land | Graybar [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					32,938,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					32,938,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					283,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					32,938,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					283,000
Total Carrying Value					33,221,000
Accumulated Depreciation					0
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					33,221,000
Balance at end of the year					33,221,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0
Balance at end of year					0
Commercial Held for Development
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					32,351,000
Initial Costs, Buildings and Improvements					19,108,000
Total Initial Acquisition Costs					51,459,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					11,359,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					40,197,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					22,621,000
Total Carrying Value					62,818,000
Accumulated Depreciation					15,097,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					62,818,000
Balance at end of the year					62,818,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					15,097,000
Balance at end of year					15,097,000
Commercial Held for Development | Hanover Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,624,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					1,624,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					0
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,104,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					520,000
Total Carrying Value					1,624,000
Accumulated Depreciation					553,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,624,000
Balance at end of the year					1,624,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					553,000
Balance at end of year					553,000
Commercial Held for Development | Circle Towers Office Bldg
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,407,000
Initial Costs, Buildings and Improvements					4,498,000
Total Initial Acquisition Costs					5,905,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,516,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,380,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					6,041,000
Total Carrying Value					7,421,000
Accumulated Depreciation					2,232,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					7,421,000
Balance at end of the year					7,421,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,232,000
Balance at end of year					2,232,000
Commercial Held for Development | Brookhaven Shopping Center
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,943,000
Initial Costs, Buildings and Improvements					7,093,000
Total Initial Acquisition Costs					12,036,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,537,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,793,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,780,000
Total Carrying Value					21,573,000
Accumulated Depreciation					11,676,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					21,573,000
Balance at end of the year					21,573,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,676,000
Balance at end of year					11,676,000
Commercial Held for Development | Bellevue Plaza retail
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					24,377,000
Initial Costs, Buildings and Improvements					7,517,000
Total Initial Acquisition Costs					31,894,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					306,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					29,920,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,280,000
Total Carrying Value					32,200,000
Accumulated Depreciation					636,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					32,200,000
Balance at end of the year					32,200,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					636,000
Balance at end of year					636,000
Commercial Held for Development | TOTAL COMMERCIAL & CORPORATE
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					32,351,000
Initial Costs, Buildings and Improvements					19,108,000
Total Initial Acquisition Costs					51,459,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					15,540,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					40,197,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					26,802,000
Total Carrying Value					66,999,000
Accumulated Depreciation					15,144,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,999,000
Balance at end of the year					66,999,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					15,144,000
Balance at end of year					15,144,000
Commercial Held for Development | Total Real Estate Owned
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					1,361,530,000
Initial Costs, Land and Land Improvements					1,788,420,000
Initial Costs, Buildings and Improvements					4,277,268,000
Total Initial Acquisition Costs					6,065,688,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,317,636,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,004,805,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					6,378,454,000
Total Carrying Value					8,383,259,000
Accumulated Depreciation					2,434,772,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					8,383,259,000
Balance at end of the year					8,383,259,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,434,772,000
Balance at end of year					2,434,772,000
Western Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					500,587,000
Initial Costs, Land and Land Improvements					876,239,000
Initial Costs, Buildings and Improvements					1,549,573,000
Total Initial Acquisition Costs					2,425,812,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					984,777,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					950,931,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,459,658,000
Total Carrying Value					3,410,589,000
Accumulated Depreciation					938,886,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					3,410,589,000
Balance at end of the year					3,410,589,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					938,886,000
Balance at end of year					938,886,000
Western Region | Harbor at Mesa Verde
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					50,358,000
Initial Costs, Land and Land Improvements					20,476,000
Initial Costs, Buildings and Improvements					28,538,000
Total Initial Acquisition Costs					49,014,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					12,949,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,058,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					40,905,000
Total Carrying Value					61,963,000
Accumulated Depreciation					26,242,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					61,963,000
Balance at end of the year					61,963,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,242,000
Balance at end of year					26,242,000
Western Region | 27 Seventy FIve Mesa Verde [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,660,000
Initial Costs, Land and Land Improvements					99,329,000
Initial Costs, Buildings and Improvements					110,644,000
Total Initial Acquisition Costs					209,973,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					91,693,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					112,333,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					189,333,000
Total Carrying Value					301,666,000
Accumulated Depreciation					72,689,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					301,666,000
Balance at end of the year					301,666,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					72,689,000
Balance at end of year					72,689,000
Western Region | Pacific Shores
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					34,112,000
Initial Costs, Land and Land Improvements					7,345,000
Initial Costs, Buildings and Improvements					22,624,000
Total Initial Acquisition Costs					29,969,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,150,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,759,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,360,000
Total Carrying Value					39,119,000
Accumulated Depreciation					19,665,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,119,000
Balance at end of the year					39,119,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,665,000
Balance at end of year					19,665,000
Western Region | Huntington Vista
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					27,972,000
Initial Costs, Land and Land Improvements					8,055,000
Initial Costs, Buildings and Improvements					22,486,000
Total Initial Acquisition Costs					30,541,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,637,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,438,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,740,000
Total Carrying Value					38,178,000
Accumulated Depreciation					18,655,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					38,178,000
Balance at end of the year					38,178,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,655,000
Balance at end of year					18,655,000
Western Region | Missions at Back Bay
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					229,000
Initial Costs, Buildings and Improvements					14,129,000
Total Initial Acquisition Costs					14,358,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,133,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,802,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					5,689,000
Total Carrying Value					16,491,000
Accumulated Depreciation					3,994,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,491,000
Balance at end of the year					16,491,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					3,994,000
Balance at end of year					3,994,000
Western Region | Coronado at Newport b North
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					62,516,000
Initial Costs, Buildings and Improvements					46,082,000
Total Initial Acquisition Costs					108,598,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					24,693,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					66,756,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					66,535,000
Total Carrying Value					133,291,000
Accumulated Depreciation					41,982,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					133,291,000
Balance at end of the year					133,291,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					41,982,000
Balance at end of year					41,982,000
Western Region | Huntington Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					50,771,000
Initial Costs, Land and Land Improvements					61,535,000
Initial Costs, Buildings and Improvements					18,017,000
Total Initial Acquisition Costs					79,552,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,132,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					62,223,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,461,000
Total Carrying Value					86,684,000
Accumulated Depreciation					16,061,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					86,684,000
Balance at end of the year					86,684,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,061,000
Balance at end of year					16,061,000
Western Region | Vista Del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,670,000
Initial Costs, Buildings and Improvements					7,080,000
Total Initial Acquisition Costs					17,750,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,062,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,830,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,982,000
Total Carrying Value					19,812,000
Accumulated Depreciation					5,769,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,812,000
Balance at end of the year					19,812,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,769,000
Balance at end of year					5,769,000
Western Region | Foxborough
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					12,071,000
Initial Costs, Buildings and Improvements					6,187,000
Total Initial Acquisition Costs					18,258,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,749,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					12,366,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,641,000
Total Carrying Value					21,007,000
Accumulated Depreciation					5,119,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					21,007,000
Balance at end of the year					21,007,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,119,000
Balance at end of year					5,119,000
Western Region | Coronado South
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					58,785,000
Initial Costs, Buildings and Improvements					50,067,000
Total Initial Acquisition Costs					108,852,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,875,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					59,277,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					67,450,000
Total Carrying Value					126,727,000
Accumulated Depreciation					40,783,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					126,727,000
Balance at end of the year					126,727,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					40,783,000
Balance at end of year					40,783,000
Western Region | 1818 Platinum Triangle
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					16,663,000
Initial Costs, Buildings and Improvements					51,905,000
Total Initial Acquisition Costs					68,568,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					470,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,693,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					52,345,000
Total Carrying Value					69,038,000
Accumulated Depreciation					13,682,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					69,038,000
Balance at end of the year					69,038,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,682,000
Balance at end of year					13,682,000
Western Region | Beach & Ocean [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					12,878,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					12,878,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					38,160,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					13,007,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					38,031,000
Total Carrying Value					51,038,000
Accumulated Depreciation					347,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					51,038,000
Balance at end of the year					51,038,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					347,000
Balance at end of year					347,000
Western Region | ORANGE COUNTY, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					193,873,000
Initial Costs, Land and Land Improvements					412,850,000
Initial Costs, Buildings and Improvements					377,759,000
Total Initial Acquisition Costs					790,609,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					412,386,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					443,008,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					759,987,000
Total Carrying Value					1,202,995,000
Accumulated Depreciation					280,469,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,202,995,000
Balance at end of the year					1,202,995,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					280,469,000
Balance at end of year					280,469,000
Western Region | 2000 Post Street
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					9,861,000
Initial Costs, Buildings and Improvements					44,578,000
Total Initial Acquisition Costs					54,439,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,965,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,241,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					53,163,000
Total Carrying Value					63,404,000
Accumulated Depreciation					24,289,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					63,404,000
Balance at end of the year					63,404,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,289,000
Balance at end of year					24,289,000
Western Region | Birch Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,365,000
Initial Costs, Buildings and Improvements					16,696,000
Total Initial Acquisition Costs					21,061,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,544,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,068,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					22,537,000
Total Carrying Value					27,605,000
Accumulated Depreciation					12,889,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					27,605,000
Balance at end of the year					27,605,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,889,000
Balance at end of year					12,889,000
Western Region | Highlands Of Marin
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,996,000
Initial Costs, Buildings and Improvements					24,868,000
Total Initial Acquisition Costs					30,864,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					25,720,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,127,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					49,457,000
Total Carrying Value					56,584,000
Accumulated Depreciation					26,904,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					56,584,000
Balance at end of the year					56,584,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,904,000
Balance at end of year					26,904,000
Western Region | Marina Playa
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,224,000
Initial Costs, Buildings and Improvements					23,916,000
Total Initial Acquisition Costs					30,140,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,482,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,908,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					32,714,000
Total Carrying Value					39,622,000
Accumulated Depreciation					18,351,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,622,000
Balance at end of the year					39,622,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,351,000
Balance at end of year					18,351,000
Western Region | River Terrace
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,310,000
Initial Costs, Land and Land Improvements					22,161,000
Initial Costs, Buildings and Improvements					40,137,000
Total Initial Acquisition Costs					62,298,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,315,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					22,359,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					43,254,000
Total Carrying Value					65,613,000
Accumulated Depreciation					23,857,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,613,000
Balance at end of the year					65,613,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,857,000
Balance at end of year					23,857,000
Western Region | CitySouth
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,031,000
Initial Costs, Buildings and Improvements					30,537,000
Total Initial Acquisition Costs					44,568,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					35,190,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,261,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					63,497,000
Total Carrying Value					79,758,000
Accumulated Depreciation					30,810,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					79,758,000
Balance at end of the year					79,758,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					30,810,000
Balance at end of year					30,810,000
Western Region | Bay Terrace
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,545,000
Initial Costs, Buildings and Improvements					14,458,000
Total Initial Acquisition Costs					23,003,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,571,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,424,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					16,150,000
Total Carrying Value					27,574,000
Accumulated Depreciation					8,710,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					27,574,000
Balance at end of the year					27,574,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,710,000
Balance at end of year					8,710,000
Western Region | Highlands of Marin Phase II
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,353,000
Initial Costs, Buildings and Improvements					18,559,000
Total Initial Acquisition Costs					23,912,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					11,059,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,753,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,218,000
Total Carrying Value					34,971,000
Accumulated Depreciation					13,438,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					34,971,000
Balance at end of the year					34,971,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,438,000
Balance at end of year					13,438,000
Western Region | Edgewater
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					30,657,000
Initial Costs, Buildings and Improvements					83,872,000
Total Initial Acquisition Costs					114,529,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,261,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					30,687,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					87,103,000
Total Carrying Value					117,790,000
Accumulated Depreciation					34,141,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					117,790,000
Balance at end of the year					117,790,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					34,141,000
Balance at end of year					34,141,000
Western Region | Almaden Lake Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					27,000,000
Initial Costs, Land and Land Improvements					594,000
Initial Costs, Buildings and Improvements					42,515,000
Total Initial Acquisition Costs					43,109,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,838,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					741,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,206,000
Total Carrying Value					47,947,000
Accumulated Depreciation					18,420,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					47,947,000
Balance at end of the year					47,947,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,420,000
Balance at end of year					18,420,000
Western Region | 388 Beale
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,253,000
Initial Costs, Buildings and Improvements					74,104,000
Total Initial Acquisition Costs					88,357,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,511,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,276,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					78,592,000
Total Carrying Value					92,868,000
Accumulated Depreciation					16,399,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					92,868,000
Balance at end of the year					92,868,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,399,000
Balance at end of year					16,399,000
Western Region | Channel @ Mission Bay [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					23,625,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					23,625,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					125,275,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					23,657,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					125,243,000
Total Carrying Value					148,900,000
Accumulated Depreciation					7,463,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					148,900,000
Balance at end of the year					148,900,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,463,000
Balance at end of year					7,463,000
Western Region | 2000 Post III
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,756,000
Initial Costs, Buildings and Improvements					7,753,000
Total Initial Acquisition Costs					9,509,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,008,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,291,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					9,226,000
Total Carrying Value					12,517,000
Accumulated Depreciation					5,535,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,517,000
Balance at end of the year					12,517,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,535,000
Balance at end of year					5,535,000
Western Region | SAN FRANCISCO, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					66,310,000
Initial Costs, Land and Land Improvements					147,421,000
Initial Costs, Buildings and Improvements					421,993,000
Total Initial Acquisition Costs					569,414,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					245,739,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					157,793,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					657,360,000
Total Carrying Value					815,153,000
Accumulated Depreciation					241,206,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					815,153,000
Balance at end of the year					815,153,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					241,206,000
Balance at end of year					241,206,000
Western Region | Rosebeach
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,414,000
Initial Costs, Buildings and Improvements					17,449,000
Total Initial Acquisition Costs					25,863,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,945,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,584,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,224,000
Total Carrying Value					28,808,000
Accumulated Depreciation					11,880,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					28,808,000
Balance at end of the year					28,808,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,880,000
Balance at end of year					11,880,000
Western Region | Ocean Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,135,000
Initial Costs, Buildings and Improvements					12,789,000
Total Initial Acquisition Costs					17,924,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,817,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,326,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,415,000
Total Carrying Value					19,741,000
Accumulated Depreciation					8,442,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,741,000
Balance at end of the year					19,741,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,442,000
Balance at end of year					8,442,000
Western Region | Tierra Del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,635,000
Initial Costs, Land and Land Improvements					39,586,000
Initial Costs, Buildings and Improvements					36,679,000
Total Initial Acquisition Costs					76,265,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,008,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					39,647,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					39,626,000
Total Carrying Value					79,273,000
Accumulated Depreciation					16,561,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					79,273,000
Balance at end of the year					79,273,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,561,000
Balance at end of year					16,561,000
Western Region | The Westerly
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					67,700,000
Initial Costs, Land and Land Improvements					48,182,000
Initial Costs, Buildings and Improvements					102,364,000
Total Initial Acquisition Costs					150,546,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					36,334,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					50,662,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					136,218,000
Total Carrying Value					186,880,000
Accumulated Depreciation					35,540,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					186,880,000
Balance at end of the year					186,880,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					35,540,000
Balance at end of year					35,540,000
Western Region | Jefferson at Marina del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					55,651,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					55,651,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					89,717,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					61,262,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					84,106,000
Total Carrying Value					145,368,000
Accumulated Depreciation					27,682,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					145,368,000
Balance at end of the year					145,368,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					27,682,000
Balance at end of year					27,682,000
Western Region | LOS ANGELES, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					100,335,000
Initial Costs, Land and Land Improvements					151,833,000
Initial Costs, Buildings and Improvements					156,492,000
Total Initial Acquisition Costs					308,325,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					132,004,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					160,155,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					280,174,000
Total Carrying Value					440,329,000
Accumulated Depreciation					91,663,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					440,329,000
Balance at end of the year					440,329,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					91,663,000
Balance at end of year					91,663,000
Western Region | Crowne Pointe
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,486,000
Initial Costs, Buildings and Improvements					6,437,000
Total Initial Acquisition Costs					8,923,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,074,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,822,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,175,000
Total Carrying Value					13,997,000
Accumulated Depreciation					7,069,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,997,000
Balance at end of the year					13,997,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,069,000
Balance at end of year					7,069,000
Western Region | Hilltop
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,174,000
Initial Costs, Buildings and Improvements					7,408,000
Total Initial Acquisition Costs					9,582,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,722,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,668,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,636,000
Total Carrying Value					13,304,000
Accumulated Depreciation					6,431,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,304,000
Balance at end of the year					13,304,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					6,431,000
Balance at end of year					6,431,000
Western Region | The Hawthorne
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					35,500,000
Initial Costs, Land and Land Improvements					6,474,000
Initial Costs, Buildings and Improvements					30,226,000
Total Initial Acquisition Costs					36,700,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,187,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,575,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					33,312,000
Total Carrying Value					39,887,000
Accumulated Depreciation					18,512,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,887,000
Balance at end of the year					39,887,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,512,000
Balance at end of year					18,512,000
Western Region | The Kennedy
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,179,000
Initial Costs, Buildings and Improvements					22,307,000
Total Initial Acquisition Costs					28,486,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,742,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,242,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					23,986,000
Total Carrying Value					30,228,000
Accumulated Depreciation					12,640,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,228,000
Balance at end of the year					30,228,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,640,000
Balance at end of year					12,640,000
Western Region | Hearthstone at Merrill Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					22,957,000
Initial Costs, Land and Land Improvements					6,848,000
Initial Costs, Buildings and Improvements					30,922,000
Total Initial Acquisition Costs					37,770,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,180,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,984,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					33,966,000
Total Carrying Value					40,950,000
Accumulated Depreciation					13,370,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					40,950,000
Balance at end of the year					40,950,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,370,000
Balance at end of year					13,370,000
Western Region | Island Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					21,284,000
Initial Costs, Buildings and Improvements					89,389,000
Total Initial Acquisition Costs					110,673,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,086,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,413,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					93,346,000
Total Carrying Value					114,759,000
Accumulated Depreciation					34,577,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					114,759,000
Balance at end of the year					114,759,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					34,577,000
Balance at end of year					34,577,000
Western Region | Borgata
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,379,000
Initial Costs, Buildings and Improvements					24,569,000
Total Initial Acquisition Costs					30,948,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					722,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,404,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					25,287,000
Total Carrying Value					31,691,000
Accumulated Depreciation					11,013,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					31,691,000
Balance at end of the year					31,691,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,013,000
Balance at end of year					11,013,000
Western Region | elements too
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					27,468,000
Initial Costs, Buildings and Improvements					72,036,000
Total Initial Acquisition Costs					99,504,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,258,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					30,100,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					83,662,000
Total Carrying Value					113,762,000
Accumulated Depreciation					33,927,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					113,762,000
Balance at end of the year					113,762,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					33,927,000
Balance at end of year					33,927,000
Western Region | 989elements
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,541,000
Initial Costs, Buildings and Improvements					45,990,000
Total Initial Acquisition Costs					54,531,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,592,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,552,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,571,000
Total Carrying Value					56,123,000
Accumulated Depreciation					13,663,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					56,123,000
Balance at end of the year					56,123,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,663,000
Balance at end of year					13,663,000
Western Region | Lightbox [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,449,000
Initial Costs, Buildings and Improvements					38,884,000
Total Initial Acquisition Costs					45,333,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					55,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,449,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					38,939,000
Total Carrying Value					45,388,000
Accumulated Depreciation					854,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					45,388,000
Balance at end of the year					45,388,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					854,000
Balance at end of year					854,000
Western Region | Waterscape [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					9,693,000
Initial Costs, Buildings and Improvements					65,176,000
Total Initial Acquisition Costs					74,869,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					50,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,693,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					65,226,000
Total Carrying Value					74,919,000
Accumulated Depreciation					1,028,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					74,919,000
Balance at end of the year					74,919,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					1,028,000
Balance at end of year					1,028,000
Western Region | SEATTLE, WA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					58,457,000
Initial Costs, Land and Land Improvements					103,975,000
Initial Costs, Buildings and Improvements					433,344,000
Total Initial Acquisition Costs					537,319,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					37,668,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					107,902,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					467,106,000
Total Carrying Value					575,008,000
Accumulated Depreciation					153,084,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					575,008,000
Balance at end of the year					575,008,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					153,084,000
Balance at end of year					153,084,000
Western Region | Villas at Carlsbad
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,517,000
Initial Costs, Buildings and Improvements					10,718,000
Total Initial Acquisition Costs					17,235,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,181,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,763,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					12,653,000
Total Carrying Value					19,416,000
Accumulated Depreciation					7,330,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,416,000
Balance at end of the year					19,416,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,330,000
Balance at end of year					7,330,000
Western Region | Boronda Manor
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,946,000
Initial Costs, Buildings and Improvements					8,982,000
Total Initial Acquisition Costs					10,928,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,398,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,169,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					17,136,000
Total Carrying Value					20,305,000
Accumulated Depreciation					8,611,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					20,305,000
Balance at end of the year					20,305,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,611,000
Balance at end of year					8,611,000
Western Region | Garden Court
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					888,000
Initial Costs, Buildings and Improvements					4,188,000
Total Initial Acquisition Costs					5,076,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,304,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,552,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,828,000
Total Carrying Value					10,380,000
Accumulated Depreciation					4,603,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,380,000
Balance at end of the year					10,380,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,603,000
Balance at end of year					4,603,000
Western Region | Cambridge Court
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,039,000
Initial Costs, Buildings and Improvements					12,883,000
Total Initial Acquisition Costs					15,922,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,266,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,274,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,914,000
Total Carrying Value					30,188,000
Accumulated Depreciation					13,065,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,188,000
Balance at end of the year					30,188,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,065,000
Balance at end of year					13,065,000
Western Region | Laurel Tree
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,304,000
Initial Costs, Buildings and Improvements					5,115,000
Total Initial Acquisition Costs					6,419,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,872,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,139,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,152,000
Total Carrying Value					12,291,000
Accumulated Depreciation					5,264,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,291,000
Balance at end of the year					12,291,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,264,000
Balance at end of year					5,264,000
Western Region | The Pointe At Harden Ranch
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,388,000
Initial Costs, Buildings and Improvements					23,854,000
Total Initial Acquisition Costs					30,242,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					25,703,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,848,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					46,097,000
Total Carrying Value					55,945,000
Accumulated Depreciation					23,292,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					55,945,000
Balance at end of the year					55,945,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,292,000
Balance at end of year					23,292,000
Western Region | The Pointe At Northridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,044,000
Initial Costs, Buildings and Improvements					8,028,000
Total Initial Acquisition Costs					10,072,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,582,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,269,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					16,385,000
Total Carrying Value					19,654,000
Accumulated Depreciation					8,761,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,654,000
Balance at end of the year					19,654,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,761,000
Balance at end of year					8,761,000
Western Region | The Pointe At Westlake
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,329,000
Initial Costs, Buildings and Improvements					5,334,000
Total Initial Acquisition Costs					6,663,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,207,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,154,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,716,000
Total Carrying Value					12,870,000
Accumulated Depreciation					5,276,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,870,000
Balance at end of the year					12,870,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,276,000
Balance at end of year					5,276,000
Western Region | MONTEREY PENINSULA, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					16,938,000
Initial Costs, Buildings and Improvements					68,384,000
Total Initial Acquisition Costs					85,322,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					76,332,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					27,405,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					134,228,000
Total Carrying Value					161,633,000
Accumulated Depreciation					68,872,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					161,633,000
Balance at end of the year					161,633,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					68,872,000
Balance at end of year					68,872,000
Western Region | Verano at Rancho Cucamonga Town Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					46,471,000
Initial Costs, Land and Land Improvements					13,557,000
Initial Costs, Buildings and Improvements					3,645,000
Total Initial Acquisition Costs					17,202,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					53,385,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					23,066,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,521,000
Total Carrying Value					70,587,000
Accumulated Depreciation					31,638,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					70,587,000
Balance at end of the year					70,587,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					31,638,000
Balance at end of year					31,638,000
Western Region | Windemere at Sycamore Highland
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,810,000
Initial Costs, Buildings and Improvements					23,450,000
Total Initial Acquisition Costs					29,260,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,656,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,100,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					25,816,000
Total Carrying Value					31,916,000
Accumulated Depreciation					16,798,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					31,916,000
Balance at end of the year					31,916,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,798,000
Balance at end of year					16,798,000
Western Region | Other Southern CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					46,471,000
Initial Costs, Land and Land Improvements					31,019,000
Initial Costs, Buildings and Improvements					50,602,000
Total Initial Acquisition Costs					81,621,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					60,039,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					41,255,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					100,405,000
Total Carrying Value					141,660,000
Accumulated Depreciation					64,208,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					141,660,000
Balance at end of the year					141,660,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					64,208,000
Balance at end of year					64,208,000
Western Region | Tualatin Heights
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,273,000
Initial Costs, Buildings and Improvements					9,134,000
Total Initial Acquisition Costs					12,407,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,517,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,839,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					15,085,000
Total Carrying Value					18,924,000
Accumulated Depreciation					9,653,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					18,924,000
Balance at end of the year					18,924,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,653,000
Balance at end of year					9,653,000
Western Region | Andover Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					16,818,000
Initial Costs, Land and Land Improvements					2,916,000
Initial Costs, Buildings and Improvements					16,995,000
Total Initial Acquisition Costs					19,911,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,174,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,210,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,875,000
Total Carrying Value					28,085,000
Accumulated Depreciation					16,127,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					28,085,000
Balance at end of the year					28,085,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,127,000
Balance at end of year					16,127,000
Western Region | Hunt Club
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					18,323,000
Initial Costs, Land and Land Improvements					6,014,000
Initial Costs, Buildings and Improvements					14,870,000
Total Initial Acquisition Costs					20,884,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,918,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,364,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,438,000
Total Carrying Value					26,802,000
Accumulated Depreciation					13,604,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					26,802,000
Balance at end of the year					26,802,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,604,000
Balance at end of year					13,604,000
Western Region | PORTLAND, OR
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					35,141,000
Initial Costs, Land and Land Improvements					12,203,000
Initial Costs, Buildings and Improvements					40,999,000
Total Initial Acquisition Costs					53,202,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,609,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					13,413,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					60,398,000
Total Carrying Value					73,811,000
Accumulated Depreciation					39,384,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					73,811,000
Balance at end of the year					73,811,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					39,384,000
Balance at end of year					39,384,000
Western Region | The Residences at Bella Terra
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					25,000,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					25,000,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					125,801,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					25,080,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					125,721,000
Total Carrying Value					150,801,000
Accumulated Depreciation					11,032,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					150,801,000
Balance at end of the year					150,801,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,032,000
Balance at end of year					11,032,000
Western Region | Los Alisos [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					17,298,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					17,298,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					69,882,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,386,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					70,794,000
Total Carrying Value					87,180,000
Accumulated Depreciation					4,449,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					87,180,000
Balance at end of the year					87,180,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,449,000
Balance at end of year					4,449,000
Mid Atlantic Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					285,450,000
Initial Costs, Land and Land Improvements					222,920,000
Initial Costs, Buildings and Improvements					886,974,000
Total Initial Acquisition Costs					1,109,894,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					617,946,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					300,649,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,427,126,000
Total Carrying Value					1,727,775,000
Accumulated Depreciation					625,493,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,727,775,000
Balance at end of the year					1,727,775,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					625,493,000
Balance at end of year					625,493,000
Mid Atlantic Region | Dominion Middle Ridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					29,820,000
Initial Costs, Land and Land Improvements					3,311,000
Initial Costs, Buildings and Improvements					13,283,000
Total Initial Acquisition Costs					16,594,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,738,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,823,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					19,509,000
Total Carrying Value					23,332,000
Accumulated Depreciation					13,634,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					23,332,000
Balance at end of the year					23,332,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,634,000
Balance at end of year					13,634,000
Mid Atlantic Region | Dominion Lake Ridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					20,372,000
Initial Costs, Land and Land Improvements					2,366,000
Initial Costs, Buildings and Improvements					8,387,000
Total Initial Acquisition Costs					10,753,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,207,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,865,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,095,000
Total Carrying Value					16,960,000
Accumulated Depreciation					9,879,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,960,000
Balance at end of the year					16,960,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,879,000
Balance at end of year					9,879,000
Mid Atlantic Region | Presidential Greens
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					11,238,000
Initial Costs, Buildings and Improvements					18,790,000
Total Initial Acquisition Costs					30,028,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,111,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,640,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					27,499,000
Total Carrying Value					39,139,000
Accumulated Depreciation					18,907,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,139,000
Balance at end of the year					39,139,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,907,000
Balance at end of year					18,907,000
Mid Atlantic Region | The Whitmore
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,418,000
Initial Costs, Buildings and Improvements					13,411,000
Total Initial Acquisition Costs					19,829,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,350,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,493,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					32,686,000
Total Carrying Value					40,179,000
Accumulated Depreciation					21,571,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					40,179,000
Balance at end of the year					40,179,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,571,000
Balance at end of year					21,571,000
Mid Atlantic Region | Ridgewood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,612,000
Initial Costs, Buildings and Improvements					20,086,000
Total Initial Acquisition Costs					25,698,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,108,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,012,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					27,794,000
Total Carrying Value					33,806,000
Accumulated Depreciation					19,540,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					33,806,000
Balance at end of the year					33,806,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,540,000
Balance at end of year					19,540,000
Mid Atlantic Region | Waterside Towers
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,139,000
Initial Costs, Buildings and Improvements					49,657,000
Total Initial Acquisition Costs					50,796,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					15,246,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					36,028,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					30,014,000
Total Carrying Value					66,042,000
Accumulated Depreciation					19,530,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,042,000
Balance at end of the year					66,042,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,530,000
Balance at end of year					19,530,000
Mid Atlantic Region | Wellington Place at Olde Town
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,037,000
Initial Costs, Land and Land Improvements					13,753,000
Initial Costs, Buildings and Improvements					36,059,000
Total Initial Acquisition Costs					49,812,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,071,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,650,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					52,233,000
Total Carrying Value					66,883,000
Accumulated Depreciation					32,364,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,883,000
Balance at end of the year					66,883,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					32,364,000
Balance at end of year					32,364,000
Mid Atlantic Region | Andover House
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,357,000
Initial Costs, Buildings and Improvements					51,577,000
Total Initial Acquisition Costs					65,934,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,173,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,373,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					54,669,000
Total Carrying Value					69,042,000
Accumulated Depreciation					24,673,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					69,042,000
Balance at end of the year					69,042,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,673,000
Balance at end of year					24,673,000
Mid Atlantic Region | Sullivan Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,137,000
Initial Costs, Buildings and Improvements					103,676,000
Total Initial Acquisition Costs					104,813,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,604,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,373,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					109,044,000
Total Carrying Value					110,417,000
Accumulated Depreciation					44,942,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					110,417,000
Balance at end of the year					110,417,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					44,942,000
Balance at end of year					44,942,000
Mid Atlantic Region | Circle Towers
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					70,606,000
Initial Costs, Land and Land Improvements					32,815,000
Initial Costs, Buildings and Improvements					107,051,000
Total Initial Acquisition Costs					139,866,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,812,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					33,105,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					117,573,000
Total Carrying Value					150,678,000
Accumulated Depreciation					45,360,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					150,678,000
Balance at end of the year					150,678,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					45,360,000
Balance at end of year					45,360,000
Mid Atlantic Region | Delancey at Shirlington
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					21,606,000
Initial Costs, Buildings and Improvements					66,765,000
Total Initial Acquisition Costs					88,371,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,770,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,632,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					68,509,000
Total Carrying Value					90,141,000
Accumulated Depreciation					26,624,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					90,141,000
Balance at end of the year					90,141,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,624,000
Balance at end of year					26,624,000
Mid Atlantic Region | View 14
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,710,000
Initial Costs, Buildings and Improvements					97,941,000
Total Initial Acquisition Costs					103,651,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,407,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,721,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					100,337,000
Total Carrying Value					106,058,000
Accumulated Depreciation					20,042,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					106,058,000
Balance at end of the year					106,058,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,042,000
Balance at end of year					20,042,000
Mid Atlantic Region | Signal Hill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					13,290,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					13,290,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					69,526,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					25,399,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					57,417,000
Total Carrying Value					82,816,000
Accumulated Depreciation					20,799,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					82,816,000
Balance at end of the year					82,816,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,799,000
Balance at end of year					20,799,000
Mid Atlantic Region | METROPOLITAN DC
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					184,172,000
Initial Costs, Land and Land Improvements					171,742,000
Initial Costs, Buildings and Improvements					599,469,000
Total Initial Acquisition Costs					771,211,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					440,149,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					232,261,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					979,034,000
Total Carrying Value					1,211,295,000
Accumulated Depreciation					335,868,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,211,295,000
Balance at end of the year					1,211,295,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					335,868,000
Balance at end of year					335,868,000
Mid Atlantic Region | Dominion Kings Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					14,525,000
Initial Costs, Land and Land Improvements					1,565,000
Initial Costs, Buildings and Improvements					7,007,000
Total Initial Acquisition Costs					8,572,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,199,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,808,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,963,000
Total Carrying Value					12,771,000
Accumulated Depreciation					8,117,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,771,000
Balance at end of the year					12,771,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,117,000
Balance at end of year					8,117,000
Mid Atlantic Region | Dominion At Eden Brook
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,361,000
Initial Costs, Buildings and Improvements					9,384,000
Total Initial Acquisition Costs					11,745,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,515,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,952,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					15,308,000
Total Carrying Value					18,260,000
Accumulated Depreciation					11,890,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					18,260,000
Balance at end of the year					18,260,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,890,000
Balance at end of year					11,890,000
Mid Atlantic Region | Ellicott Grove
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,920,000
Initial Costs, Buildings and Improvements					9,099,000
Total Initial Acquisition Costs					12,019,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					23,075,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,306,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,788,000
Total Carrying Value					35,094,000
Accumulated Depreciation					22,140,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,094,000
Balance at end of the year					35,094,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					22,140,000
Balance at end of year					22,140,000
Mid Atlantic Region | Dominion Constant Friendship
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					8,783,000
Initial Costs, Land and Land Improvements					903,000
Initial Costs, Buildings and Improvements					4,669,000
Total Initial Acquisition Costs					5,572,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,941,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,277,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,236,000
Total Carrying Value					9,513,000
Accumulated Depreciation					5,965,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					9,513,000
Balance at end of the year					9,513,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,965,000
Balance at end of year					5,965,000
Mid Atlantic Region | Lakeside Mill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					12,569,000
Initial Costs, Land and Land Improvements					2,666,000
Initial Costs, Buildings and Improvements					10,109,000
Total Initial Acquisition Costs					12,775,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,581,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,985,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,371,000
Total Carrying Value					17,356,000
Accumulated Depreciation					10,818,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					17,356,000
Balance at end of the year					17,356,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,818,000
Balance at end of year					10,818,000
Mid Atlantic Region | Tamar Meadow
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,145,000
Initial Costs, Buildings and Improvements					17,150,000
Total Initial Acquisition Costs					21,295,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,089,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,577,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					21,807,000
Total Carrying Value					26,384,000
Accumulated Depreciation					14,882,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					26,384,000
Balance at end of the year					26,384,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					14,882,000
Balance at end of year					14,882,000
Mid Atlantic Region | Calvertbs Walk
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,408,000
Initial Costs, Buildings and Improvements					24,692,000
Total Initial Acquisition Costs					29,100,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,766,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,726,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,140,000
Total Carrying Value					35,866,000
Accumulated Depreciation					19,763,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,866,000
Balance at end of the year					35,866,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,763,000
Balance at end of year					19,763,000
Mid Atlantic Region | Arborview Apartments
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,653,000
Initial Costs, Buildings and Improvements					23,952,000
Total Initial Acquisition Costs					28,605,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,731,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,209,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,127,000
Total Carrying Value					36,336,000
Accumulated Depreciation					20,296,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					36,336,000
Balance at end of the year					36,336,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,296,000
Balance at end of year					20,296,000
Mid Atlantic Region | Liriope Apartments
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,620,000
Initial Costs, Buildings and Improvements					6,791,000
Total Initial Acquisition Costs					8,411,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,250,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,646,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,015,000
Total Carrying Value					9,661,000
Accumulated Depreciation					5,090,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					9,661,000
Balance at end of the year					9,661,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,090,000
Balance at end of year					5,090,000
Mid Atlantic Region | 20 Lambourne
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,834,000
Initial Costs, Land and Land Improvements					11,750,000
Initial Costs, Buildings and Improvements					45,590,000
Total Initial Acquisition Costs					57,340,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,433,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					12,018,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					50,755,000
Total Carrying Value					62,773,000
Accumulated Depreciation					21,218,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					62,773,000
Balance at end of the year					62,773,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,218,000
Balance at end of year					21,218,000
Mid Atlantic Region | Domain Brewers Hill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,669,000
Initial Costs, Buildings and Improvements					40,630,000
Total Initial Acquisition Costs					45,299,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					581,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,678,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					41,202,000
Total Carrying Value					45,880,000
Accumulated Depreciation					10,343,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					45,880,000
Balance at end of the year					45,880,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,343,000
Balance at end of year					10,343,000
Mid Atlantic Region | BALTIMORE, MD
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					66,711,000
Initial Costs, Land and Land Improvements					41,660,000
Initial Costs, Buildings and Improvements					199,073,000
Total Initial Acquisition Costs					240,733,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					69,161,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					47,182,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					262,712,000
Total Carrying Value					309,894,000
Accumulated Depreciation					150,522,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					309,894,000
Balance at end of the year					309,894,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					150,522,000
Balance at end of year					150,522,000
Mid Atlantic Region | Dominion English Hills
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,979,000
Initial Costs, Buildings and Improvements					11,524,000
Total Initial Acquisition Costs					13,503,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,224,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,873,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					18,854,000
Total Carrying Value					21,727,000
Accumulated Depreciation					11,134,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					21,727,000
Balance at end of the year					21,727,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,134,000
Balance at end of year					11,134,000
Mid Atlantic Region | Gayton Pointe Townhomes
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					826,000
Initial Costs, Buildings and Improvements					5,148,000
Total Initial Acquisition Costs					5,974,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					29,434,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,420,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,988,000
Total Carrying Value					35,408,000
Accumulated Depreciation					25,999,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,408,000
Balance at end of the year					35,408,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					25,999,000
Balance at end of year					25,999,000
Mid Atlantic Region | Waterside At Ironbridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,844,000
Initial Costs, Buildings and Improvements					13,239,000
Total Initial Acquisition Costs					15,083,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,335,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,299,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,119,000
Total Carrying Value					22,418,000
Accumulated Depreciation					13,123,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,418,000
Balance at end of the year					22,418,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,123,000
Balance at end of year					13,123,000
Mid Atlantic Region | Carriage Homes at Wyndham
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					474,000
Initial Costs, Buildings and Improvements					30,997,000
Total Initial Acquisition Costs					31,471,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,560,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,801,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					35,230,000
Total Carrying Value					39,031,000
Accumulated Depreciation					23,205,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,031,000
Balance at end of the year					39,031,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,205,000
Balance at end of year					23,205,000
Mid Atlantic Region | Legacy at Mayland
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					34,567,000
Initial Costs, Land and Land Improvements					0
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					0
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,954,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,975,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					18,979,000
Total Carrying Value					20,954,000
Accumulated Depreciation					18,906,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					20,954,000
Balance at end of the year					20,954,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,906,000
Balance at end of year					18,906,000
Mid Atlantic Region | RICHMOND, VA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					34,567,000
Initial Costs, Land and Land Improvements					5,123,000
Initial Costs, Buildings and Improvements					60,908,000
Total Initial Acquisition Costs					66,031,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					73,507,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,368,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					125,170,000
Total Carrying Value					139,538,000
Accumulated Depreciation					92,367,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					139,538,000
Balance at end of the year					139,538,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					92,367,000
Balance at end of year					92,367,000
Mid Atlantic Region | Eastwind
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					155,000
Initial Costs, Buildings and Improvements					5,317,000
Total Initial Acquisition Costs					5,472,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,374,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					659,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,187,000
Total Carrying Value					11,846,000
Accumulated Depreciation					9,145,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					11,846,000
Balance at end of the year					11,846,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,145,000
Balance at end of year					9,145,000
Mid Atlantic Region | Dominion Waterside At Lynnhaven
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,824,000
Initial Costs, Buildings and Improvements					4,107,000
Total Initial Acquisition Costs					5,931,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,369,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,337,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					9,963,000
Total Carrying Value					12,300,000
Accumulated Depreciation					7,634,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,300,000
Balance at end of the year					12,300,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,634,000
Balance at end of year					7,634,000
Mid Atlantic Region | Heather Lake
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					617,000
Initial Costs, Buildings and Improvements					3,400,000
Total Initial Acquisition Costs					4,017,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,120,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,205,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					12,932,000
Total Carrying Value					14,137,000
Accumulated Depreciation					12,126,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					14,137,000
Balance at end of the year					14,137,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,126,000
Balance at end of year					12,126,000
Mid Atlantic Region | Dominion Yorkshire Downs
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,089,000
Initial Costs, Buildings and Improvements					8,582,000
Total Initial Acquisition Costs					9,671,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,123,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,594,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,200,000
Total Carrying Value					15,794,000
Accumulated Depreciation					9,290,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					15,794,000
Balance at end of the year					15,794,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,290,000
Balance at end of year					9,290,000
Mid Atlantic Region | NORFOLK, VA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,685,000
Initial Costs, Buildings and Improvements					21,406,000
Total Initial Acquisition Costs					25,091,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					28,986,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,795,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					48,282,000
Total Carrying Value					54,077,000
Accumulated Depreciation					38,195,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					54,077,000
Balance at end of the year					54,077,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,195,000
Balance at end of year					38,195,000
Mid Atlantic Region | Greens At Schumaker Pond
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					710,000
Initial Costs, Buildings and Improvements					6,118,000
Total Initial Acquisition Costs					6,828,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,143,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,043,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,928,000
Total Carrying Value					12,971,000
Accumulated Depreciation					8,541,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,971,000
Balance at end of the year					12,971,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,541,000
Balance at end of year					8,541,000
Mid Atlantic Region | OTHER MID-ATLANTIC
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					710,000
Initial Costs, Buildings and Improvements					6,118,000
Total Initial Acquisition Costs					6,828,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,143,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,043,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,928,000
Total Carrying Value					12,971,000
Accumulated Depreciation					8,541,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,971,000
Balance at end of the year					12,971,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,541,000
Balance at end of year					8,541,000
Mid Atlantic Region | DelRey Tower [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					297,000
Initial Costs, Buildings and Improvements					12,786,000
Total Initial Acquisition Costs					13,083,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					111,790,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,447,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					115,426,000
Total Carrying Value					124,873,000
Accumulated Depreciation					2,382,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					124,873,000
Balance at end of the year					124,873,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,382,000
Balance at end of year					2,382,000
Mid Atlantic Region | Capitol View on 14th
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					31,393,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					31,393,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					94,301,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					31,394,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					94,300,000
Total Carrying Value					125,694,000
Accumulated Depreciation					11,374,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					125,694,000
Balance at end of the year					125,694,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,374,000
Balance at end of year					11,374,000
Mid Atlantic Region | Domain College Park [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					31,337,000
Initial Costs, Land and Land Improvements					7,300,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					7,300,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					57,935,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,306,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					57,929,000
Total Carrying Value					65,235,000
Accumulated Depreciation					4,247,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,235,000
Balance at end of the year					65,235,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,247,000
Balance at end of year					4,247,000
Southeastern Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					172,646,000
Initial Costs, Land and Land Improvements					94,379,000
Initial Costs, Buildings and Improvements					378,689,000
Total Initial Acquisition Costs					473,068,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					313,371,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					128,777,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					657,662,000
Total Carrying Value					786,439,000
Accumulated Depreciation					445,033,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					786,439,000
Balance at end of the year					786,439,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					445,033,000
Balance at end of year					445,033,000
Southeastern Region | Summit West
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,176,000
Initial Costs, Buildings and Improvements					4,710,000
Total Initial Acquisition Costs					6,886,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,513,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,236,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					12,163,000
Total Carrying Value					15,399,000
Accumulated Depreciation					10,443,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					15,399,000
Balance at end of the year					15,399,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,443,000
Balance at end of year					10,443,000
Southeastern Region | The Breyley
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,780,000
Initial Costs, Buildings and Improvements					2,458,000
Total Initial Acquisition Costs					4,238,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,167,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,346,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					18,059,000
Total Carrying Value					21,405,000
Accumulated Depreciation					16,232,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					21,405,000
Balance at end of the year					21,405,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,232,000
Balance at end of year					16,232,000
Southeastern Region | Lakewood Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					18,526,000
Initial Costs, Land and Land Improvements					1,395,000
Initial Costs, Buildings and Improvements					10,647,000
Total Initial Acquisition Costs					12,042,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,972,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,329,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					18,685,000
Total Carrying Value					21,014,000
Accumulated Depreciation					13,790,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					21,014,000
Balance at end of the year					21,014,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,790,000
Balance at end of year					13,790,000
Southeastern Region | Bay Meadow
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,893,000
Initial Costs, Buildings and Improvements					9,254,000
Total Initial Acquisition Costs					12,147,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,416,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,277,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					18,286,000
Total Carrying Value					22,563,000
Accumulated Depreciation					13,550,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,563,000
Balance at end of the year					22,563,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,550,000
Balance at end of year					13,550,000
Southeastern Region | Cambridge Woods
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					12,713,000
Initial Costs, Land and Land Improvements					1,791,000
Initial Costs, Buildings and Improvements					7,166,000
Total Initial Acquisition Costs					8,957,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,655,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,613,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,999,000
Total Carrying Value					17,612,000
Accumulated Depreciation					10,681,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					17,612,000
Balance at end of the year					17,612,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,681,000
Balance at end of year					10,681,000
Southeastern Region | Sugar Mill Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,242,000
Initial Costs, Buildings and Improvements					7,553,000
Total Initial Acquisition Costs					9,795,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,846,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,734,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,907,000
Total Carrying Value					16,641,000
Accumulated Depreciation					8,998,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,641,000
Balance at end of the year					16,641,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,998,000
Balance at end of year					8,998,000
Southeastern Region | Inlet Bay
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					7,702,000
Initial Costs, Buildings and Improvements					23,150,000
Total Initial Acquisition Costs					30,852,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,657,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,211,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					36,298,000
Total Carrying Value					45,509,000
Accumulated Depreciation					25,585,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					45,509,000
Balance at end of the year					45,509,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					25,585,000
Balance at end of year					25,585,000
Southeastern Region | MacAlpine Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,869,000
Initial Costs, Buildings and Improvements					36,858,000
Total Initial Acquisition Costs					47,727,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,384,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,408,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					43,703,000
Total Carrying Value					55,111,000
Accumulated Depreciation					27,162,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					55,111,000
Balance at end of the year					55,111,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					27,162,000
Balance at end of year					27,162,000
Southeastern Region | The Vintage Lofts at West End
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,611,000
Initial Costs, Buildings and Improvements					37,663,000
Total Initial Acquisition Costs					44,274,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					15,827,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					15,120,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					44,981,000
Total Carrying Value					60,101,000
Accumulated Depreciation					19,020,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					60,101,000
Balance at end of the year					60,101,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,020,000
Balance at end of year					19,020,000
Southeastern Region | TAMPA, FL
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					31,239,000
Initial Costs, Land and Land Improvements					37,459,000
Initial Costs, Buildings and Improvements					139,459,000
Total Initial Acquisition Costs					176,918,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					98,437,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					54,274,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					221,081,000
Total Carrying Value					275,355,000
Accumulated Depreciation					145,461,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					275,355,000
Balance at end of the year					275,355,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					145,461,000
Balance at end of year					145,461,000
Southeastern Region | Seabrook
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,846,000
Initial Costs, Buildings and Improvements					4,155,000
Total Initial Acquisition Costs					6,001,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,052,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,681,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,372,000
Total Carrying Value					14,053,000
Accumulated Depreciation					9,077,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					14,053,000
Balance at end of the year					14,053,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,077,000
Balance at end of year					9,077,000
Southeastern Region | The Canopy Apartment Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,895,000
Initial Costs, Buildings and Improvements					6,456,000
Total Initial Acquisition Costs					9,351,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					21,457,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,470,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					25,338,000
Total Carrying Value					30,808,000
Accumulated Depreciation					22,904,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,808,000
Balance at end of the year					30,808,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					22,904,000
Balance at end of year					22,904,000
Southeastern Region | Altamira Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,533,000
Initial Costs, Buildings and Improvements					11,076,000
Total Initial Acquisition Costs					12,609,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,241,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,450,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,400,000
Total Carrying Value					32,850,000
Accumulated Depreciation					24,329,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					32,850,000
Balance at end of the year					32,850,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,329,000
Balance at end of year					24,329,000
Southeastern Region | Regatta Shore
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					757,000
Initial Costs, Buildings and Improvements					6,608,000
Total Initial Acquisition Costs					7,365,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					15,549,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,018,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,896,000
Total Carrying Value					22,914,000
Accumulated Depreciation					16,423,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,914,000
Balance at end of the year					22,914,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,423,000
Balance at end of year					16,423,000
Southeastern Region | Alafaya Woods
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					18,064,000
Initial Costs, Land and Land Improvements					1,653,000
Initial Costs, Buildings and Improvements					9,042,000
Total Initial Acquisition Costs					10,695,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,911,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,522,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					17,084,000
Total Carrying Value					19,606,000
Accumulated Depreciation					12,624,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,606,000
Balance at end of the year					19,606,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,624,000
Balance at end of year					12,624,000
Southeastern Region | Los Altos
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					21,942,000
Initial Costs, Land and Land Improvements					2,804,000
Initial Costs, Buildings and Improvements					12,349,000
Total Initial Acquisition Costs					15,153,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,494,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,020,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					21,627,000
Total Carrying Value					25,647,000
Accumulated Depreciation					14,273,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					25,647,000
Balance at end of the year					25,647,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					14,273,000
Balance at end of year					14,273,000
Southeastern Region | Lotus Landing
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,185,000
Initial Costs, Buildings and Improvements					8,639,000
Total Initial Acquisition Costs					10,824,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,569,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,841,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					17,552,000
Total Carrying Value					20,393,000
Accumulated Depreciation					11,184,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					20,393,000
Balance at end of the year					20,393,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,184,000
Balance at end of year					11,184,000
Southeastern Region | Seville On The Green
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,282,000
Initial Costs, Buildings and Improvements					6,498,000
Total Initial Acquisition Costs					7,780,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,722,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,705,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					12,797,000
Total Carrying Value					14,502,000
Accumulated Depreciation					8,546,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					14,502,000
Balance at end of the year					14,502,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,546,000
Balance at end of year					8,546,000
Southeastern Region | Ashton @ Waterford
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					23,388,000
Initial Costs, Land and Land Improvements					3,872,000
Initial Costs, Buildings and Improvements					17,538,000
Total Initial Acquisition Costs					21,410,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,049,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,179,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					21,280,000
Total Carrying Value					25,459,000
Accumulated Depreciation					12,963,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					25,459,000
Balance at end of the year					25,459,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,963,000
Balance at end of year					12,963,000
Southeastern Region | Arbors at Lee Vista DCO
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,692,000
Initial Costs, Buildings and Improvements					12,860,000
Total Initial Acquisition Costs					19,552,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					12,591,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,220,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,923,000
Total Carrying Value					32,143,000
Accumulated Depreciation					18,328,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					32,143,000
Balance at end of the year					32,143,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,328,000
Balance at end of year					18,328,000
Southeastern Region | ORLANDO, FL
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					63,394,000
Initial Costs, Land and Land Improvements					25,519,000
Initial Costs, Buildings and Improvements					95,221,000
Total Initial Acquisition Costs					120,740,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					117,635,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					36,106,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					202,269,000
Total Carrying Value					238,375,000
Accumulated Depreciation					150,651,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					238,375,000
Balance at end of the year					238,375,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					150,651,000
Balance at end of year					150,651,000
Southeastern Region | Legacy Hill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,148,000
Initial Costs, Buildings and Improvements					5,867,000
Total Initial Acquisition Costs					7,015,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,636,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,762,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,889,000
Total Carrying Value					15,651,000
Accumulated Depreciation					10,830,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					15,651,000
Balance at end of the year					15,651,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,830,000
Balance at end of year					10,830,000
Southeastern Region | Hickory Run
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,469,000
Initial Costs, Buildings and Improvements					11,584,000
Total Initial Acquisition Costs					13,053,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,761,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,139,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,675,000
Total Carrying Value					22,814,000
Accumulated Depreciation					13,482,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,814,000
Balance at end of the year					22,814,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,482,000
Balance at end of year					13,482,000
Southeastern Region | Carrington Hills
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,117,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					2,117,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					33,846,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,462,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,501,000
Total Carrying Value					35,963,000
Accumulated Depreciation					20,064,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,963,000
Balance at end of the year					35,963,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,064,000
Balance at end of year					20,064,000
Southeastern Region | Brookridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					708,000
Initial Costs, Buildings and Improvements					5,461,000
Total Initial Acquisition Costs					6,169,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,500,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,143,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					9,526,000
Total Carrying Value					10,669,000
Accumulated Depreciation					6,641,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,669,000
Balance at end of the year					10,669,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					6,641,000
Balance at end of year					6,641,000
Southeastern Region | Breckenridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					766,000
Initial Costs, Buildings and Improvements					7,714,000
Total Initial Acquisition Costs					8,480,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,357,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,258,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,579,000
Total Carrying Value					12,837,000
Accumulated Depreciation					7,704,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,837,000
Balance at end of the year					12,837,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,704,000
Balance at end of year					7,704,000
Southeastern Region | Colonnade
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					16,677,000
Initial Costs, Land and Land Improvements					1,460,000
Initial Costs, Buildings and Improvements					16,015,000
Total Initial Acquisition Costs					17,475,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,934,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,946,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,463,000
Total Carrying Value					22,409,000
Accumulated Depreciation					11,461,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,409,000
Balance at end of the year					22,409,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,461,000
Balance at end of year					11,461,000
Southeastern Region | The Preserve at Brentwood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					22,157,000
Initial Costs, Land and Land Improvements					3,182,000
Initial Costs, Buildings and Improvements					24,674,000
Total Initial Acquisition Costs					27,856,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,276,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,508,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					30,624,000
Total Carrying Value					34,132,000
Accumulated Depreciation					19,951,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					34,132,000
Balance at end of the year					34,132,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,951,000
Balance at end of year					19,951,000
Southeastern Region | Polo Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,583,000
Initial Costs, Buildings and Improvements					16,293,000
Total Initial Acquisition Costs					20,876,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					16,042,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,643,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,275,000
Total Carrying Value					36,918,000
Accumulated Depreciation					20,471,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					36,918,000
Balance at end of the year					36,918,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,471,000
Balance at end of year					20,471,000
Southeastern Region | NASHVILLE, TN
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					38,834,000
Initial Costs, Land and Land Improvements					15,433,000
Initial Costs, Buildings and Improvements					87,608,000
Total Initial Acquisition Costs					103,041,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					88,352,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,861,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					169,532,000
Total Carrying Value					191,393,000
Accumulated Depreciation					110,604,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					191,393,000
Balance at end of the year					191,393,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					110,604,000
Balance at end of year					110,604,000
Southeastern Region | The Reserve and Park at Riverbridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					15,968,000
Initial Costs, Buildings and Improvements					56,401,000
Total Initial Acquisition Costs					72,369,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,947,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,536,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					64,780,000
Total Carrying Value					81,316,000
Accumulated Depreciation					38,317,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					81,316,000
Balance at end of the year					81,316,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,317,000
Balance at end of year					38,317,000
Southeastern Region | OTHER FLORIDA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					15,968,000
Initial Costs, Buildings and Improvements					56,401,000
Total Initial Acquisition Costs					72,369,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,947,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,536,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					64,780,000
Total Carrying Value					81,316,000
Accumulated Depreciation					38,317,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					81,316,000
Balance at end of the year					81,316,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,317,000
Balance at end of year					38,317,000
Northeast Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					269,748,000
Initial Costs, Land and Land Improvements					293,247,000
Initial Costs, Buildings and Improvements					1,182,479,000
Total Initial Acquisition Costs					1,475,726,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					126,125,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					292,681,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,309,170,000
Total Carrying Value					1,601,851,000
Accumulated Depreciation					256,550,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,601,851,000
Balance at end of the year					1,601,851,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					256,550,000
Balance at end of year					256,550,000
Northeast Region | Garrison Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,591,000
Initial Costs, Buildings and Improvements					91,027,000
Total Initial Acquisition Costs					96,618,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,048,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,631,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					97,035,000
Total Carrying Value					102,666,000
Accumulated Depreciation					23,767,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					102,666,000
Balance at end of the year					102,666,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,767,000
Balance at end of year					23,767,000
Northeast Region | Ridge at Blue Hills
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					22,839,000
Initial Costs, Land and Land Improvements					6,039,000
Initial Costs, Buildings and Improvements					34,869,000
Total Initial Acquisition Costs					40,908,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,238,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,102,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					36,044,000
Total Carrying Value					42,146,000
Accumulated Depreciation					9,052,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					42,146,000
Balance at end of the year					42,146,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,052,000
Balance at end of year					9,052,000
Northeast Region | Inwood West
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					56,447,000
Initial Costs, Land and Land Improvements					20,778,000
Initial Costs, Buildings and Improvements					88,096,000
Total Initial Acquisition Costs					108,874,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,034,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					19,309,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					92,599,000
Total Carrying Value					111,908,000
Accumulated Depreciation					20,102,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					111,908,000
Balance at end of the year					111,908,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,102,000
Balance at end of year					20,102,000
Northeast Region | 14 North
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,961,000
Initial Costs, Buildings and Improvements					51,175,000
Total Initial Acquisition Costs					62,136,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,563,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,999,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					55,700,000
Total Carrying Value					66,699,000
Accumulated Depreciation					12,750,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,699,000
Balance at end of the year					66,699,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,750,000
Balance at end of year					12,750,000
Northeast Region | BOSTON, MA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					79,286,000
Initial Costs, Land and Land Improvements					43,369,000
Initial Costs, Buildings and Improvements					265,167,000
Total Initial Acquisition Costs					308,536,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,883,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					42,041,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					281,378,000
Total Carrying Value					323,419,000
Accumulated Depreciation					65,671,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					323,419,000
Balance at end of the year					323,419,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					65,671,000
Balance at end of year					65,671,000
Northeast Region | 10 Hanover Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					190,462,000
Initial Costs, Land and Land Improvements					41,432,000
Initial Costs, Buildings and Improvements					218,983,000
Total Initial Acquisition Costs					260,415,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,396,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					41,481,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					227,330,000
Total Carrying Value					268,811,000
Accumulated Depreciation					42,678,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					268,811,000
Balance at end of the year					268,811,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					42,678,000
Balance at end of year					42,678,000
Northeast Region | 21 Chelsea
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					36,399,000
Initial Costs, Buildings and Improvements					107,154,000
Total Initial Acquisition Costs					143,553,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,915,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					36,399,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					118,069,000
Total Carrying Value					154,468,000
Accumulated Depreciation					20,910,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					154,468,000
Balance at end of the year					154,468,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,910,000
Balance at end of year					20,910,000
Northeast Region | View 34 [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					114,410,000
Initial Costs, Buildings and Improvements					324,920,000
Total Initial Acquisition Costs					439,330,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					85,635,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					115,024,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					409,941,000
Total Carrying Value					524,965,000
Accumulated Depreciation					72,318,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					524,965,000
Balance at end of the year					524,965,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					72,318,000
Balance at end of year					72,318,000
Northeast Region | 95 Wall Street
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					57,637,000
Initial Costs, Buildings and Improvements					266,255,000
Total Initial Acquisition Costs					323,892,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,296,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					57,736,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					272,452,000
Total Carrying Value					330,188,000
Accumulated Depreciation					54,973,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					330,188,000
Balance at end of the year					330,188,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					54,973,000
Balance at end of year					54,973,000
Northeast Region | NEW YORK, NY
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					190,462,000
Initial Costs, Land and Land Improvements					249,878,000
Initial Costs, Buildings and Improvements					917,312,000
Total Initial Acquisition Costs					1,167,190,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					111,242,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					250,640,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,027,792,000
Total Carrying Value					1,278,432,000
Accumulated Depreciation					190,879,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,278,432,000
Balance at end of the year					1,278,432,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					190,879,000
Balance at end of year					190,879,000
Southwestern Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					133,099,000
Initial Costs, Land and Land Improvements					99,870,000
Initial Costs, Buildings and Improvements					257,677,000
Total Initial Acquisition Costs					357,547,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					83,174,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					115,095,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					325,626,000
Total Carrying Value					440,721,000
Accumulated Depreciation					149,451,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					440,721,000
Balance at end of the year					440,721,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					149,451,000
Balance at end of year					149,451,000
Southwestern Region | THIRTY377
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,023,000
Initial Costs, Land and Land Improvements					24,036,000
Initial Costs, Buildings and Improvements					32,951,000
Total Initial Acquisition Costs					56,987,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,162,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					24,311,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					40,838,000
Total Carrying Value					65,149,000
Accumulated Depreciation					21,663,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,149,000
Balance at end of the year					65,149,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,663,000
Balance at end of year					21,663,000
Southwestern Region | Legacy Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					72,415,000
Initial Costs, Land and Land Improvements					16,882,000
Initial Costs, Buildings and Improvements					100,102,000
Total Initial Acquisition Costs					116,984,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,325,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					17,280,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					107,029,000
Total Carrying Value					124,309,000
Accumulated Depreciation					44,321,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					124,309,000
Balance at end of the year					124,309,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					44,321,000
Balance at end of year					44,321,000
Southwestern Region | Garden Oaks
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,132,000
Initial Costs, Buildings and Improvements					5,367,000
Total Initial Acquisition Costs					7,499,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,631,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,936,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,194,000
Total Carrying Value					9,130,000
Accumulated Depreciation					1,842,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					9,130,000
Balance at end of the year					9,130,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					1,842,000
Balance at end of year					1,842,000
Southwestern Region | Glenwood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					7,903,000
Initial Costs, Buildings and Improvements					554,000
Total Initial Acquisition Costs					8,457,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,897,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,159,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,195,000
Total Carrying Value					10,354,000
Accumulated Depreciation					1,366,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,354,000
Balance at end of the year					10,354,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					1,366,000
Balance at end of year					1,366,000
Southwestern Region | Talisker of Addison
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,440,000
Initial Costs, Buildings and Improvements					634,000
Total Initial Acquisition Costs					11,074,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,917,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,841,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,150,000
Total Carrying Value					12,991,000
Accumulated Depreciation					1,836,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,991,000
Balance at end of the year					12,991,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					1,836,000
Balance at end of year					1,836,000
Southwestern Region | Springhaven
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,688,000
Initial Costs, Buildings and Improvements					3,354,000
Total Initial Acquisition Costs					10,042,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,289,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,350,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,981,000
Total Carrying Value					11,331,000
Accumulated Depreciation					2,231,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					11,331,000
Balance at end of the year					11,331,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,231,000
Balance at end of year					2,231,000
Southwestern Region | Clipper Pointe
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					13,221,000
Initial Costs, Buildings and Improvements					2,507,000
Total Initial Acquisition Costs					15,728,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,398,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,948,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					3,178,000
Total Carrying Value					18,126,000
Accumulated Depreciation					2,618,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					18,126,000
Balance at end of the year					18,126,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,618,000
Balance at end of year					2,618,000
Southwestern Region | Highlands of Preston
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,151,000
Initial Costs, Buildings and Improvements					8,168,000
Total Initial Acquisition Costs					10,319,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					31,139,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,989,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					35,469,000
Total Carrying Value					41,458,000
Accumulated Depreciation					24,269,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					41,458,000
Balance at end of the year					41,458,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,269,000
Balance at end of year					24,269,000
Southwestern Region | DALLAS, TX
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					102,438,000
Initial Costs, Land and Land Improvements					83,453,000
Initial Costs, Buildings and Improvements					153,637,000
Total Initial Acquisition Costs					237,090,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					55,758,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					96,814,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					196,034,000
Total Carrying Value					292,848,000
Accumulated Depreciation					100,146,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					292,848,000
Balance at end of the year					292,848,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					100,146,000
Balance at end of year					100,146,000
Southwestern Region | Barton Creek Landing
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,151,000
Initial Costs, Buildings and Improvements					14,269,000
Total Initial Acquisition Costs					17,420,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					22,118,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,807,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					34,731,000
Total Carrying Value					39,538,000
Accumulated Depreciation					20,260,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,538,000
Balance at end of the year					39,538,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,260,000
Balance at end of year					20,260,000
Southwestern Region | Residences at the Domain
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,661,000
Initial Costs, Land and Land Improvements					4,034,000
Initial Costs, Buildings and Improvements					55,256,000
Total Initial Acquisition Costs					59,290,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,608,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,200,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					57,698,000
Total Carrying Value					61,898,000
Accumulated Depreciation					21,988,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					61,898,000
Balance at end of the year					61,898,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,988,000
Balance at end of year					21,988,000
Southwestern Region | Red Stone Ranch
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,084,000
Initial Costs, Buildings and Improvements					17,646,000
Total Initial Acquisition Costs					22,730,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,625,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,115,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					19,240,000
Total Carrying Value					24,355,000
Accumulated Depreciation					3,687,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					24,355,000
Balance at end of the year					24,355,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					3,687,000
Balance at end of year					3,687,000
Southwestern Region | Lakeline Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,148,000
Initial Costs, Buildings and Improvements					16,869,000
Total Initial Acquisition Costs					21,017,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,065,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,159,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					17,923,000
Total Carrying Value					22,082,000
Accumulated Depreciation					3,370,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,082,000
Balance at end of the year					22,082,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					3,370,000
Balance at end of year					3,370,000
Southwestern Region | AUSTIN, TX
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,661,000
Initial Costs, Land and Land Improvements					16,417,000
Initial Costs, Buildings and Improvements					104,040,000
Total Initial Acquisition Costs					120,457,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					27,416,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					18,281,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					129,592,000
Total Carrying Value					147,873,000
Accumulated Depreciation					49,305,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					147,873,000
Balance at end of the year					147,873,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					49,305,000
Balance at end of year					49,305,000
Corporate Joint Venture [Member]
Real Estate Owned, Gross [Roll Forward]
Real estate acquired		0	129,437,000	0
Retirement of fully depreciated assets		-112,344,000	-356,303,000	0
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Accumulated depreciation on retirements of fully depreciated assets		($4,228,000)	($20,662,000)	$0
[1]	Includes unallocated accruals and capital expenditures.The aggregate cost for federal income tax purposes was approximately $7.7 billion at December 31, 2014. The estimated depreciable lives for all buildings in the latest Consolidated Statements of Operations are 35 to 55 years.

Schedule_III_Real_Estate_Owned3

Schedule III - Real Estate Owned (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	1 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014
Real Estate and Accumulated Depreciation [Line Items]
Total Carrying Value		$8,383,259,000	$8,207,977,000	$8,055,828,000
Accumulated Depreciation		2,434,772,000	2,208,794,000	1,924,682,000
Aggregate cost for federal income tax purposes		7,700,000,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year		8,207,977,000	8,055,828,000	8,074,471,000
Real estate acquired		231,225,000	0	141,648,000
Capital expenditures and development		326,461,000	452,057,000	422,480,000
Real estate sold	-140,000,000	-269,681,000	-70,687,000	-559,154,000
Retirement of fully depreciated assets		0	0	-13,945,000
Hurricane related impairment of assets		-379,000	-2,355,000	-9,672,000
Balance at end of the year		8,383,259,000	8,207,977,000	8,055,828,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year		2,208,794,000	1,924,682,000	1,831,727,000
Depreciation expense for the year		356,673,000	339,326,000	340,800,000
Accumulated depreciation on sales		-126,151,000	-34,794,000	-233,207,000
Accumulated depreciation on retirements of fully depreciated asset		0	-1,132,000	-13,945,000
Write off of accumulated depreciation on hurricane related impaired assets		-316,000	0	-693,000
Balance at end of year		2,434,772,000	2,208,794,000	1,924,682,000
Estimated depreciable lives of buildings range beginning
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for all buildings		35 years
Estimated depreciable lives of buildings range end
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for all buildings		55 years
Other
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0	[1]
Initial Costs, Land and Land Improvements					0	[1]
Initial Costs, Buildings and Improvements					0	[1]
Total Initial Acquisition Costs					0	[1]
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,181,000	[1]
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					0	[1]
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					4,181,000	[1]
Total Carrying Value					4,181,000	[1]
Accumulated Depreciation					47,000	[1]
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					4,181,000	[1]
Balance at end of the year					4,181,000	[1]
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					47,000	[1]
Balance at end of year					47,000	[1]
TOTAL CORPORATE
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					0
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					0
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,181,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					0
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					4,181,000
Total Carrying Value					4,181,000
Accumulated Depreciation					47,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					4,181,000
Balance at end of the year					4,181,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					47,000
Balance at end of year					47,000
Real Estate Under Development
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					24,584,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					24,584,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					153,048,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					24,584,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					153,048,000
Total Carrying Value					177,632,000
Accumulated Depreciation					0
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					177,632,000
Balance at end of the year					177,632,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0
Balance at end of year					0
Land
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					144,830,000
Initial Costs, Buildings and Improvements					2,768,000
Total Initial Acquisition Costs					147,598,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					23,655,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					151,891,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					19,362,000
Total Carrying Value					171,253,000
Accumulated Depreciation					4,215,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					171,253,000
Balance at end of the year					171,253,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,215,000
Balance at end of year					4,215,000
Commercial Held for Development
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					32,351,000
Initial Costs, Buildings and Improvements					19,108,000
Total Initial Acquisition Costs					51,459,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					11,359,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					40,197,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					22,621,000
Total Carrying Value					62,818,000
Accumulated Depreciation					15,097,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					62,818,000
Balance at end of the year					62,818,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					15,097,000
Balance at end of year					15,097,000
Commercial Held for Development | TOTAL COMMERCIAL & CORPORATE
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					32,351,000
Initial Costs, Buildings and Improvements					19,108,000
Total Initial Acquisition Costs					51,459,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					15,540,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					40,197,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					26,802,000
Total Carrying Value					66,999,000
Accumulated Depreciation					15,144,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,999,000
Balance at end of the year					66,999,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					15,144,000
Balance at end of year					15,144,000
Commercial Held for Development | Total Real Estate Owned
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					1,361,530,000
Initial Costs, Land and Land Improvements					1,788,420,000
Initial Costs, Buildings and Improvements					4,277,268,000
Total Initial Acquisition Costs					6,065,688,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,317,636,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,004,805,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					6,378,454,000
Total Carrying Value					8,383,259,000
Accumulated Depreciation					2,434,772,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					8,383,259,000
Balance at end of the year					8,383,259,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,434,772,000
Balance at end of year					2,434,772,000
Western Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					500,587,000
Initial Costs, Land and Land Improvements					876,239,000
Initial Costs, Buildings and Improvements					1,549,573,000
Total Initial Acquisition Costs					2,425,812,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					984,777,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					950,931,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					2,459,658,000
Total Carrying Value					3,410,589,000
Accumulated Depreciation					938,886,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					3,410,589,000
Balance at end of the year					3,410,589,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					938,886,000
Balance at end of year					938,886,000
Western Region | Harbor at Mesa Verde
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					50,358,000
Initial Costs, Land and Land Improvements					20,476,000
Initial Costs, Buildings and Improvements					28,538,000
Total Initial Acquisition Costs					49,014,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					12,949,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,058,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					40,905,000
Total Carrying Value					61,963,000
Accumulated Depreciation					26,242,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					61,963,000
Balance at end of the year					61,963,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,242,000
Balance at end of year					26,242,000
Western Region | 27 Seventy FIve Mesa Verde [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,660,000
Initial Costs, Land and Land Improvements					99,329,000
Initial Costs, Buildings and Improvements					110,644,000
Total Initial Acquisition Costs					209,973,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					91,693,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					112,333,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					189,333,000
Total Carrying Value					301,666,000
Accumulated Depreciation					72,689,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					301,666,000
Balance at end of the year					301,666,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					72,689,000
Balance at end of year					72,689,000
Western Region | Pacific Shores
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					34,112,000
Initial Costs, Land and Land Improvements					7,345,000
Initial Costs, Buildings and Improvements					22,624,000
Total Initial Acquisition Costs					29,969,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,150,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,759,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,360,000
Total Carrying Value					39,119,000
Accumulated Depreciation					19,665,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,119,000
Balance at end of the year					39,119,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,665,000
Balance at end of year					19,665,000
Western Region | Huntington Vista
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					27,972,000
Initial Costs, Land and Land Improvements					8,055,000
Initial Costs, Buildings and Improvements					22,486,000
Total Initial Acquisition Costs					30,541,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,637,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,438,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,740,000
Total Carrying Value					38,178,000
Accumulated Depreciation					18,655,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					38,178,000
Balance at end of the year					38,178,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,655,000
Balance at end of year					18,655,000
Western Region | Missions at Back Bay
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					229,000
Initial Costs, Buildings and Improvements					14,129,000
Total Initial Acquisition Costs					14,358,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,133,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,802,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					5,689,000
Total Carrying Value					16,491,000
Accumulated Depreciation					3,994,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,491,000
Balance at end of the year					16,491,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					3,994,000
Balance at end of year					3,994,000
Western Region | Coronado at Newport b North
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					62,516,000
Initial Costs, Buildings and Improvements					46,082,000
Total Initial Acquisition Costs					108,598,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					24,693,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					66,756,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					66,535,000
Total Carrying Value					133,291,000
Accumulated Depreciation					41,982,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					133,291,000
Balance at end of the year					133,291,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					41,982,000
Balance at end of year					41,982,000
Western Region | Huntington Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					50,771,000
Initial Costs, Land and Land Improvements					61,535,000
Initial Costs, Buildings and Improvements					18,017,000
Total Initial Acquisition Costs					79,552,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,132,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					62,223,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,461,000
Total Carrying Value					86,684,000
Accumulated Depreciation					16,061,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					86,684,000
Balance at end of the year					86,684,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,061,000
Balance at end of year					16,061,000
Western Region | Vista Del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,670,000
Initial Costs, Buildings and Improvements					7,080,000
Total Initial Acquisition Costs					17,750,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,062,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,830,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,982,000
Total Carrying Value					19,812,000
Accumulated Depreciation					5,769,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,812,000
Balance at end of the year					19,812,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,769,000
Balance at end of year					5,769,000
Western Region | Coronado South
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					58,785,000
Initial Costs, Buildings and Improvements					50,067,000
Total Initial Acquisition Costs					108,852,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,875,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					59,277,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					67,450,000
Total Carrying Value					126,727,000
Accumulated Depreciation					40,783,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					126,727,000
Balance at end of the year					126,727,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					40,783,000
Balance at end of year					40,783,000
Western Region | ORANGE COUNTY, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					193,873,000
Initial Costs, Land and Land Improvements					412,850,000
Initial Costs, Buildings and Improvements					377,759,000
Total Initial Acquisition Costs					790,609,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					412,386,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					443,008,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					759,987,000
Total Carrying Value					1,202,995,000
Accumulated Depreciation					280,469,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,202,995,000
Balance at end of the year					1,202,995,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					280,469,000
Balance at end of year					280,469,000
Western Region | 2000 Post Street
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					9,861,000
Initial Costs, Buildings and Improvements					44,578,000
Total Initial Acquisition Costs					54,439,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,965,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,241,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					53,163,000
Total Carrying Value					63,404,000
Accumulated Depreciation					24,289,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					63,404,000
Balance at end of the year					63,404,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,289,000
Balance at end of year					24,289,000
Western Region | Birch Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,365,000
Initial Costs, Buildings and Improvements					16,696,000
Total Initial Acquisition Costs					21,061,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,544,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,068,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					22,537,000
Total Carrying Value					27,605,000
Accumulated Depreciation					12,889,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					27,605,000
Balance at end of the year					27,605,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,889,000
Balance at end of year					12,889,000
Western Region | Highlands Of Marin
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,996,000
Initial Costs, Buildings and Improvements					24,868,000
Total Initial Acquisition Costs					30,864,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					25,720,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,127,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					49,457,000
Total Carrying Value					56,584,000
Accumulated Depreciation					26,904,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					56,584,000
Balance at end of the year					56,584,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,904,000
Balance at end of year					26,904,000
Western Region | Marina Playa
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,224,000
Initial Costs, Buildings and Improvements					23,916,000
Total Initial Acquisition Costs					30,140,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,482,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,908,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					32,714,000
Total Carrying Value					39,622,000
Accumulated Depreciation					18,351,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,622,000
Balance at end of the year					39,622,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,351,000
Balance at end of year					18,351,000
Western Region | The Westerly
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					67,700,000
Initial Costs, Land and Land Improvements					48,182,000
Initial Costs, Buildings and Improvements					102,364,000
Total Initial Acquisition Costs					150,546,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					36,334,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					50,662,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					136,218,000
Total Carrying Value					186,880,000
Accumulated Depreciation					35,540,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					186,880,000
Balance at end of the year					186,880,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					35,540,000
Balance at end of year					35,540,000
Western Region | River Terrace
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,310,000
Initial Costs, Land and Land Improvements					22,161,000
Initial Costs, Buildings and Improvements					40,137,000
Total Initial Acquisition Costs					62,298,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,315,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					22,359,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					43,254,000
Total Carrying Value					65,613,000
Accumulated Depreciation					23,857,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,613,000
Balance at end of the year					65,613,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,857,000
Balance at end of year					23,857,000
Western Region | CitySouth
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,031,000
Initial Costs, Buildings and Improvements					30,537,000
Total Initial Acquisition Costs					44,568,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					35,190,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,261,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					63,497,000
Total Carrying Value					79,758,000
Accumulated Depreciation					30,810,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					79,758,000
Balance at end of the year					79,758,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					30,810,000
Balance at end of year					30,810,000
Western Region | Bay Terrace
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,545,000
Initial Costs, Buildings and Improvements					14,458,000
Total Initial Acquisition Costs					23,003,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,571,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,424,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					16,150,000
Total Carrying Value					27,574,000
Accumulated Depreciation					8,710,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					27,574,000
Balance at end of the year					27,574,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,710,000
Balance at end of year					8,710,000
Western Region | Highlands of Marin Phase II
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,353,000
Initial Costs, Buildings and Improvements					18,559,000
Total Initial Acquisition Costs					23,912,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					11,059,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,753,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,218,000
Total Carrying Value					34,971,000
Accumulated Depreciation					13,438,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					34,971,000
Balance at end of the year					34,971,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,438,000
Balance at end of year					13,438,000
Western Region | Edgewater
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					30,657,000
Initial Costs, Buildings and Improvements					83,872,000
Total Initial Acquisition Costs					114,529,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,261,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					30,687,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					87,103,000
Total Carrying Value					117,790,000
Accumulated Depreciation					34,141,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					117,790,000
Balance at end of the year					117,790,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					34,141,000
Balance at end of year					34,141,000
Western Region | Almaden Lake Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					27,000,000
Initial Costs, Land and Land Improvements					594,000
Initial Costs, Buildings and Improvements					42,515,000
Total Initial Acquisition Costs					43,109,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,838,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					741,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,206,000
Total Carrying Value					47,947,000
Accumulated Depreciation					18,420,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					47,947,000
Balance at end of the year					47,947,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,420,000
Balance at end of year					18,420,000
Western Region | SAN FRANCISCO, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					66,310,000
Initial Costs, Land and Land Improvements					147,421,000
Initial Costs, Buildings and Improvements					421,993,000
Total Initial Acquisition Costs					569,414,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					245,739,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					157,793,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					657,360,000
Total Carrying Value					815,153,000
Accumulated Depreciation					241,206,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					815,153,000
Balance at end of the year					815,153,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					241,206,000
Balance at end of year					241,206,000
Western Region | Rosebeach
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,414,000
Initial Costs, Buildings and Improvements					17,449,000
Total Initial Acquisition Costs					25,863,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,945,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,584,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,224,000
Total Carrying Value					28,808,000
Accumulated Depreciation					11,880,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					28,808,000
Balance at end of the year					28,808,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,880,000
Balance at end of year					11,880,000
Western Region | Ocean Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,135,000
Initial Costs, Buildings and Improvements					12,789,000
Total Initial Acquisition Costs					17,924,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,817,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,326,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,415,000
Total Carrying Value					19,741,000
Accumulated Depreciation					8,442,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,741,000
Balance at end of the year					19,741,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,442,000
Balance at end of year					8,442,000
Western Region | Other Southern CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					46,471,000
Initial Costs, Land and Land Improvements					31,019,000
Initial Costs, Buildings and Improvements					50,602,000
Total Initial Acquisition Costs					81,621,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					60,039,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					41,255,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					100,405,000
Total Carrying Value					141,660,000
Accumulated Depreciation					64,208,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					141,660,000
Balance at end of the year					141,660,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					64,208,000
Balance at end of year					64,208,000
Western Region | Tierra Del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,635,000
Initial Costs, Land and Land Improvements					39,586,000
Initial Costs, Buildings and Improvements					36,679,000
Total Initial Acquisition Costs					76,265,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,008,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					39,647,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					39,626,000
Total Carrying Value					79,273,000
Accumulated Depreciation					16,561,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					79,273,000
Balance at end of the year					79,273,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,561,000
Balance at end of year					16,561,000
Western Region | LOS ANGELES, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					100,335,000
Initial Costs, Land and Land Improvements					151,833,000
Initial Costs, Buildings and Improvements					156,492,000
Total Initial Acquisition Costs					308,325,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					132,004,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					160,155,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					280,174,000
Total Carrying Value					440,329,000
Accumulated Depreciation					91,663,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					440,329,000
Balance at end of the year					440,329,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					91,663,000
Balance at end of year					91,663,000
Western Region | Crowne Pointe
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,486,000
Initial Costs, Buildings and Improvements					6,437,000
Total Initial Acquisition Costs					8,923,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,074,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,822,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,175,000
Total Carrying Value					13,997,000
Accumulated Depreciation					7,069,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,997,000
Balance at end of the year					13,997,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,069,000
Balance at end of year					7,069,000
Western Region | Hilltop
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,174,000
Initial Costs, Buildings and Improvements					7,408,000
Total Initial Acquisition Costs					9,582,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,722,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,668,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,636,000
Total Carrying Value					13,304,000
Accumulated Depreciation					6,431,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,304,000
Balance at end of the year					13,304,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					6,431,000
Balance at end of year					6,431,000
Western Region | The Kennedy
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,179,000
Initial Costs, Buildings and Improvements					22,307,000
Total Initial Acquisition Costs					28,486,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,742,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,242,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					23,986,000
Total Carrying Value					30,228,000
Accumulated Depreciation					12,640,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,228,000
Balance at end of the year					30,228,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,640,000
Balance at end of year					12,640,000
Western Region | Hearthstone at Merrill Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					22,957,000
Initial Costs, Land and Land Improvements					6,848,000
Initial Costs, Buildings and Improvements					30,922,000
Total Initial Acquisition Costs					37,770,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,180,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,984,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					33,966,000
Total Carrying Value					40,950,000
Accumulated Depreciation					13,370,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					40,950,000
Balance at end of the year					40,950,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,370,000
Balance at end of year					13,370,000
Western Region | Island Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					21,284,000
Initial Costs, Buildings and Improvements					89,389,000
Total Initial Acquisition Costs					110,673,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,086,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,413,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					93,346,000
Total Carrying Value					114,759,000
Accumulated Depreciation					34,577,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					114,759,000
Balance at end of the year					114,759,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					34,577,000
Balance at end of year					34,577,000
Western Region | SEATTLE, WA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					58,457,000
Initial Costs, Land and Land Improvements					103,975,000
Initial Costs, Buildings and Improvements					433,344,000
Total Initial Acquisition Costs					537,319,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					37,668,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					107,902,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					467,106,000
Total Carrying Value					575,008,000
Accumulated Depreciation					153,084,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					575,008,000
Balance at end of the year					575,008,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					153,084,000
Balance at end of year					153,084,000
Western Region | Villas at Carlsbad
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,517,000
Initial Costs, Buildings and Improvements					10,718,000
Total Initial Acquisition Costs					17,235,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,181,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,763,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					12,653,000
Total Carrying Value					19,416,000
Accumulated Depreciation					7,330,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,416,000
Balance at end of the year					19,416,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,330,000
Balance at end of year					7,330,000
Western Region | Boronda Manor
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,946,000
Initial Costs, Buildings and Improvements					8,982,000
Total Initial Acquisition Costs					10,928,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,398,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,169,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					17,136,000
Total Carrying Value					20,305,000
Accumulated Depreciation					8,611,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					20,305,000
Balance at end of the year					20,305,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,611,000
Balance at end of year					8,611,000
Western Region | Garden Court
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					888,000
Initial Costs, Buildings and Improvements					4,188,000
Total Initial Acquisition Costs					5,076,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,304,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,552,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,828,000
Total Carrying Value					10,380,000
Accumulated Depreciation					4,603,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,380,000
Balance at end of the year					10,380,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,603,000
Balance at end of year					4,603,000
Western Region | Cambridge Court
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,039,000
Initial Costs, Buildings and Improvements					12,883,000
Total Initial Acquisition Costs					15,922,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,266,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,274,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,914,000
Total Carrying Value					30,188,000
Accumulated Depreciation					13,065,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,188,000
Balance at end of the year					30,188,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,065,000
Balance at end of year					13,065,000
Western Region | Laurel Tree
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,304,000
Initial Costs, Buildings and Improvements					5,115,000
Total Initial Acquisition Costs					6,419,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,872,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,139,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,152,000
Total Carrying Value					12,291,000
Accumulated Depreciation					5,264,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,291,000
Balance at end of the year					12,291,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,264,000
Balance at end of year					5,264,000
Western Region | The Pointe At Harden Ranch
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,388,000
Initial Costs, Buildings and Improvements					23,854,000
Total Initial Acquisition Costs					30,242,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					25,703,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,848,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					46,097,000
Total Carrying Value					55,945,000
Accumulated Depreciation					23,292,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					55,945,000
Balance at end of the year					55,945,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,292,000
Balance at end of year					23,292,000
Western Region | The Pointe At Northridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,044,000
Initial Costs, Buildings and Improvements					8,028,000
Total Initial Acquisition Costs					10,072,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,582,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,269,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					16,385,000
Total Carrying Value					19,654,000
Accumulated Depreciation					8,761,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,654,000
Balance at end of the year					19,654,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,761,000
Balance at end of year					8,761,000
Western Region | The Pointe At Westlake
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,329,000
Initial Costs, Buildings and Improvements					5,334,000
Total Initial Acquisition Costs					6,663,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,207,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,154,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,716,000
Total Carrying Value					12,870,000
Accumulated Depreciation					5,276,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,870,000
Balance at end of the year					12,870,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,276,000
Balance at end of year					5,276,000
Western Region | MONTEREY PENINSULA, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					16,938,000
Initial Costs, Buildings and Improvements					68,384,000
Total Initial Acquisition Costs					85,322,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					76,332,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					27,405,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					134,228,000
Total Carrying Value					161,633,000
Accumulated Depreciation					68,872,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					161,633,000
Balance at end of the year					161,633,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					68,872,000
Balance at end of year					68,872,000
Western Region | Verano at Rancho Cucamonga Town Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					46,471,000
Initial Costs, Land and Land Improvements					13,557,000
Initial Costs, Buildings and Improvements					3,645,000
Total Initial Acquisition Costs					17,202,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					53,385,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					23,066,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,521,000
Total Carrying Value					70,587,000
Accumulated Depreciation					31,638,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					70,587,000
Balance at end of the year					70,587,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					31,638,000
Balance at end of year					31,638,000
Western Region | Tualatin Heights
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,273,000
Initial Costs, Buildings and Improvements					9,134,000
Total Initial Acquisition Costs					12,407,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,517,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,839,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					15,085,000
Total Carrying Value					18,924,000
Accumulated Depreciation					9,653,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					18,924,000
Balance at end of the year					18,924,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,653,000
Balance at end of year					9,653,000
Western Region | Andover Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					16,818,000
Initial Costs, Land and Land Improvements					2,916,000
Initial Costs, Buildings and Improvements					16,995,000
Total Initial Acquisition Costs					19,911,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,174,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,210,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,875,000
Total Carrying Value					28,085,000
Accumulated Depreciation					16,127,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					28,085,000
Balance at end of the year					28,085,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,127,000
Balance at end of year					16,127,000
Western Region | Hunt Club
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					18,323,000
Initial Costs, Land and Land Improvements					6,014,000
Initial Costs, Buildings and Improvements					14,870,000
Total Initial Acquisition Costs					20,884,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,918,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,364,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,438,000
Total Carrying Value					26,802,000
Accumulated Depreciation					13,604,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					26,802,000
Balance at end of the year					26,802,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,604,000
Balance at end of year					13,604,000
Western Region | PORTLAND, OR
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					35,141,000
Initial Costs, Land and Land Improvements					12,203,000
Initial Costs, Buildings and Improvements					40,999,000
Total Initial Acquisition Costs					53,202,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,609,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					13,413,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					60,398,000
Total Carrying Value					73,811,000
Accumulated Depreciation					39,384,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					73,811,000
Balance at end of the year					73,811,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					39,384,000
Balance at end of year					39,384,000
Mid Atlantic Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					285,450,000
Initial Costs, Land and Land Improvements					222,920,000
Initial Costs, Buildings and Improvements					886,974,000
Total Initial Acquisition Costs					1,109,894,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					617,946,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					300,649,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,427,126,000
Total Carrying Value					1,727,775,000
Accumulated Depreciation					625,493,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,727,775,000
Balance at end of the year					1,727,775,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					625,493,000
Balance at end of year					625,493,000
Mid Atlantic Region | The Whitmore
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,418,000
Initial Costs, Buildings and Improvements					13,411,000
Total Initial Acquisition Costs					19,829,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,350,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,493,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					32,686,000
Total Carrying Value					40,179,000
Accumulated Depreciation					21,571,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					40,179,000
Balance at end of the year					40,179,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,571,000
Balance at end of year					21,571,000
Mid Atlantic Region | Ridgewood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,612,000
Initial Costs, Buildings and Improvements					20,086,000
Total Initial Acquisition Costs					25,698,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,108,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,012,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					27,794,000
Total Carrying Value					33,806,000
Accumulated Depreciation					19,540,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					33,806,000
Balance at end of the year					33,806,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,540,000
Balance at end of year					19,540,000
Mid Atlantic Region | Wellington Place at Olde Town
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,037,000
Initial Costs, Land and Land Improvements					13,753,000
Initial Costs, Buildings and Improvements					36,059,000
Total Initial Acquisition Costs					49,812,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,071,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,650,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					52,233,000
Total Carrying Value					66,883,000
Accumulated Depreciation					32,364,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,883,000
Balance at end of the year					66,883,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					32,364,000
Balance at end of year					32,364,000
Mid Atlantic Region | Andover House
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,357,000
Initial Costs, Buildings and Improvements					51,577,000
Total Initial Acquisition Costs					65,934,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,173,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,373,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					54,669,000
Total Carrying Value					69,042,000
Accumulated Depreciation					24,673,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					69,042,000
Balance at end of the year					69,042,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,673,000
Balance at end of year					24,673,000
Mid Atlantic Region | Sullivan Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,137,000
Initial Costs, Buildings and Improvements					103,676,000
Total Initial Acquisition Costs					104,813,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,604,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,373,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					109,044,000
Total Carrying Value					110,417,000
Accumulated Depreciation					44,942,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					110,417,000
Balance at end of the year					110,417,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					44,942,000
Balance at end of year					44,942,000
Mid Atlantic Region | Circle Towers
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					70,606,000
Initial Costs, Land and Land Improvements					32,815,000
Initial Costs, Buildings and Improvements					107,051,000
Total Initial Acquisition Costs					139,866,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,812,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					33,105,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					117,573,000
Total Carrying Value					150,678,000
Accumulated Depreciation					45,360,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					150,678,000
Balance at end of the year					150,678,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					45,360,000
Balance at end of year					45,360,000
Mid Atlantic Region | Delancey at Shirlington
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					21,606,000
Initial Costs, Buildings and Improvements					66,765,000
Total Initial Acquisition Costs					88,371,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,770,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,632,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					68,509,000
Total Carrying Value					90,141,000
Accumulated Depreciation					26,624,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					90,141,000
Balance at end of the year					90,141,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,624,000
Balance at end of year					26,624,000
Mid Atlantic Region | METROPOLITAN DC
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					184,172,000
Initial Costs, Land and Land Improvements					171,742,000
Initial Costs, Buildings and Improvements					599,469,000
Total Initial Acquisition Costs					771,211,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					440,149,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					232,261,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					979,034,000
Total Carrying Value					1,211,295,000
Accumulated Depreciation					335,868,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,211,295,000
Balance at end of the year					1,211,295,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					335,868,000
Balance at end of year					335,868,000
Mid Atlantic Region | Lakeside Mill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					12,569,000
Initial Costs, Land and Land Improvements					2,666,000
Initial Costs, Buildings and Improvements					10,109,000
Total Initial Acquisition Costs					12,775,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,581,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,985,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,371,000
Total Carrying Value					17,356,000
Accumulated Depreciation					10,818,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					17,356,000
Balance at end of the year					17,356,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,818,000
Balance at end of year					10,818,000
Mid Atlantic Region | Tamar Meadow
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,145,000
Initial Costs, Buildings and Improvements					17,150,000
Total Initial Acquisition Costs					21,295,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,089,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,577,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					21,807,000
Total Carrying Value					26,384,000
Accumulated Depreciation					14,882,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					26,384,000
Balance at end of the year					26,384,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					14,882,000
Balance at end of year					14,882,000
Mid Atlantic Region | Calvertbs Walk
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,408,000
Initial Costs, Buildings and Improvements					24,692,000
Total Initial Acquisition Costs					29,100,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,766,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,726,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,140,000
Total Carrying Value					35,866,000
Accumulated Depreciation					19,763,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,866,000
Balance at end of the year					35,866,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,763,000
Balance at end of year					19,763,000
Mid Atlantic Region | Liriope Apartments
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,620,000
Initial Costs, Buildings and Improvements					6,791,000
Total Initial Acquisition Costs					8,411,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,250,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,646,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,015,000
Total Carrying Value					9,661,000
Accumulated Depreciation					5,090,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					9,661,000
Balance at end of the year					9,661,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,090,000
Balance at end of year					5,090,000
Mid Atlantic Region | 20 Lambourne
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,834,000
Initial Costs, Land and Land Improvements					11,750,000
Initial Costs, Buildings and Improvements					45,590,000
Total Initial Acquisition Costs					57,340,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,433,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					12,018,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					50,755,000
Total Carrying Value					62,773,000
Accumulated Depreciation					21,218,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					62,773,000
Balance at end of the year					62,773,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,218,000
Balance at end of year					21,218,000
Mid Atlantic Region | BALTIMORE, MD
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					66,711,000
Initial Costs, Land and Land Improvements					41,660,000
Initial Costs, Buildings and Improvements					199,073,000
Total Initial Acquisition Costs					240,733,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					69,161,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					47,182,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					262,712,000
Total Carrying Value					309,894,000
Accumulated Depreciation					150,522,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					309,894,000
Balance at end of the year					309,894,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					150,522,000
Balance at end of year					150,522,000
Mid Atlantic Region | DelRey Tower [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					297,000
Initial Costs, Buildings and Improvements					12,786,000
Total Initial Acquisition Costs					13,083,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					111,790,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,447,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					115,426,000
Total Carrying Value					124,873,000
Accumulated Depreciation					2,382,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					124,873,000
Balance at end of the year					124,873,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,382,000
Balance at end of year					2,382,000
Southeastern Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					172,646,000
Initial Costs, Land and Land Improvements					94,379,000
Initial Costs, Buildings and Improvements					378,689,000
Total Initial Acquisition Costs					473,068,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					313,371,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					128,777,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					657,662,000
Total Carrying Value					786,439,000
Accumulated Depreciation					445,033,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					786,439,000
Balance at end of the year					786,439,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					445,033,000
Balance at end of year					445,033,000
Southeastern Region | Sugar Mill Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,242,000
Initial Costs, Buildings and Improvements					7,553,000
Total Initial Acquisition Costs					9,795,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,846,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,734,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,907,000
Total Carrying Value					16,641,000
Accumulated Depreciation					8,998,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,641,000
Balance at end of the year					16,641,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,998,000
Balance at end of year					8,998,000
Southeastern Region | Inlet Bay
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					7,702,000
Initial Costs, Buildings and Improvements					23,150,000
Total Initial Acquisition Costs					30,852,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,657,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,211,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					36,298,000
Total Carrying Value					45,509,000
Accumulated Depreciation					25,585,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					45,509,000
Balance at end of the year					45,509,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					25,585,000
Balance at end of year					25,585,000
Southeastern Region | MacAlpine Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,869,000
Initial Costs, Buildings and Improvements					36,858,000
Total Initial Acquisition Costs					47,727,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,384,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,408,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					43,703,000
Total Carrying Value					55,111,000
Accumulated Depreciation					27,162,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					55,111,000
Balance at end of the year					55,111,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					27,162,000
Balance at end of year					27,162,000
Southeastern Region | TAMPA, FL
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					31,239,000
Initial Costs, Land and Land Improvements					37,459,000
Initial Costs, Buildings and Improvements					139,459,000
Total Initial Acquisition Costs					176,918,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					98,437,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					54,274,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					221,081,000
Total Carrying Value					275,355,000
Accumulated Depreciation					145,461,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					275,355,000
Balance at end of the year					275,355,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					145,461,000
Balance at end of year					145,461,000
Southeastern Region | Legacy Hill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,148,000
Initial Costs, Buildings and Improvements					5,867,000
Total Initial Acquisition Costs					7,015,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,636,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,762,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,889,000
Total Carrying Value					15,651,000
Accumulated Depreciation					10,830,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					15,651,000
Balance at end of the year					15,651,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,830,000
Balance at end of year					10,830,000
Southeastern Region | Hickory Run
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,469,000
Initial Costs, Buildings and Improvements					11,584,000
Total Initial Acquisition Costs					13,053,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,761,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,139,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,675,000
Total Carrying Value					22,814,000
Accumulated Depreciation					13,482,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,814,000
Balance at end of the year					22,814,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,482,000
Balance at end of year					13,482,000
Southeastern Region | Carrington Hills
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,117,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					2,117,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					33,846,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,462,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,501,000
Total Carrying Value					35,963,000
Accumulated Depreciation					20,064,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,963,000
Balance at end of the year					35,963,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,064,000
Balance at end of year					20,064,000
Southeastern Region | Brookridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					708,000
Initial Costs, Buildings and Improvements					5,461,000
Total Initial Acquisition Costs					6,169,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,500,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,143,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					9,526,000
Total Carrying Value					10,669,000
Accumulated Depreciation					6,641,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,669,000
Balance at end of the year					10,669,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					6,641,000
Balance at end of year					6,641,000
Southeastern Region | Breckenridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					766,000
Initial Costs, Buildings and Improvements					7,714,000
Total Initial Acquisition Costs					8,480,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,357,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,258,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,579,000
Total Carrying Value					12,837,000
Accumulated Depreciation					7,704,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,837,000
Balance at end of the year					12,837,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,704,000
Balance at end of year					7,704,000
Southeastern Region | Polo Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,583,000
Initial Costs, Buildings and Improvements					16,293,000
Total Initial Acquisition Costs					20,876,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					16,042,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,643,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,275,000
Total Carrying Value					36,918,000
Accumulated Depreciation					20,471,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					36,918,000
Balance at end of the year					36,918,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,471,000
Balance at end of year					20,471,000
Southeastern Region | NASHVILLE, TN
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					38,834,000
Initial Costs, Land and Land Improvements					15,433,000
Initial Costs, Buildings and Improvements					87,608,000
Total Initial Acquisition Costs					103,041,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					88,352,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,861,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					169,532,000
Total Carrying Value					191,393,000
Accumulated Depreciation					110,604,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					191,393,000
Balance at end of the year					191,393,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					110,604,000
Balance at end of year					110,604,000
Southeastern Region | The Reserve and Park at Riverbridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					15,968,000
Initial Costs, Buildings and Improvements					56,401,000
Total Initial Acquisition Costs					72,369,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,947,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,536,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					64,780,000
Total Carrying Value					81,316,000
Accumulated Depreciation					38,317,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					81,316,000
Balance at end of the year					81,316,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,317,000
Balance at end of year					38,317,000
Southeastern Region | OTHER FLORIDA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					15,968,000
Initial Costs, Buildings and Improvements					56,401,000
Total Initial Acquisition Costs					72,369,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,947,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,536,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					64,780,000
Total Carrying Value					81,316,000
Accumulated Depreciation					38,317,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					81,316,000
Balance at end of the year					81,316,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,317,000
Balance at end of year					38,317,000
Northeast Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					269,748,000
Initial Costs, Land and Land Improvements					293,247,000
Initial Costs, Buildings and Improvements					1,182,479,000
Total Initial Acquisition Costs					1,475,726,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					126,125,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					292,681,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,309,170,000
Total Carrying Value					1,601,851,000
Accumulated Depreciation					256,550,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,601,851,000
Balance at end of the year					1,601,851,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					256,550,000
Balance at end of year					256,550,000
Northeast Region | Inwood West
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					56,447,000
Initial Costs, Land and Land Improvements					20,778,000
Initial Costs, Buildings and Improvements					88,096,000
Total Initial Acquisition Costs					108,874,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,034,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					19,309,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					92,599,000
Total Carrying Value					111,908,000
Accumulated Depreciation					20,102,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					111,908,000
Balance at end of the year					111,908,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,102,000
Balance at end of year					20,102,000
Northeast Region | 14 North
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,961,000
Initial Costs, Buildings and Improvements					51,175,000
Total Initial Acquisition Costs					62,136,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,563,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,999,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					55,700,000
Total Carrying Value					66,699,000
Accumulated Depreciation					12,750,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,699,000
Balance at end of the year					66,699,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,750,000
Balance at end of year					12,750,000
Northeast Region | BOSTON, MA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					79,286,000
Initial Costs, Land and Land Improvements					43,369,000
Initial Costs, Buildings and Improvements					265,167,000
Total Initial Acquisition Costs					308,536,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,883,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					42,041,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					281,378,000
Total Carrying Value					323,419,000
Accumulated Depreciation					65,671,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					323,419,000
Balance at end of the year					323,419,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					65,671,000
Balance at end of year					65,671,000
Northeast Region | 10 Hanover Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					190,462,000
Initial Costs, Land and Land Improvements					41,432,000
Initial Costs, Buildings and Improvements					218,983,000
Total Initial Acquisition Costs					260,415,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,396,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					41,481,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					227,330,000
Total Carrying Value					268,811,000
Accumulated Depreciation					42,678,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					268,811,000
Balance at end of the year					268,811,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					42,678,000
Balance at end of year					42,678,000
Northeast Region | 95 Wall Street
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					57,637,000
Initial Costs, Buildings and Improvements					266,255,000
Total Initial Acquisition Costs					323,892,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,296,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					57,736,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					272,452,000
Total Carrying Value					330,188,000
Accumulated Depreciation					54,973,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					330,188,000
Balance at end of the year					330,188,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					54,973,000
Balance at end of year					54,973,000
Northeast Region | NEW YORK, NY
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					190,462,000
Initial Costs, Land and Land Improvements					249,878,000
Initial Costs, Buildings and Improvements					917,312,000
Total Initial Acquisition Costs					1,167,190,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					111,242,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					250,640,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,027,792,000
Total Carrying Value					1,278,432,000
Accumulated Depreciation					190,879,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,278,432,000
Balance at end of the year					1,278,432,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					190,879,000
Balance at end of year					190,879,000
Southwestern Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					133,099,000
Initial Costs, Land and Land Improvements					99,870,000
Initial Costs, Buildings and Improvements					257,677,000
Total Initial Acquisition Costs					357,547,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					83,174,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					115,095,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					325,626,000
Total Carrying Value					440,721,000
Accumulated Depreciation					149,451,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					440,721,000
Balance at end of the year					440,721,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					149,451,000
Balance at end of year					149,451,000
Southwestern Region | THIRTY377
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,023,000
Initial Costs, Land and Land Improvements					24,036,000
Initial Costs, Buildings and Improvements					32,951,000
Total Initial Acquisition Costs					56,987,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,162,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					24,311,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					40,838,000
Total Carrying Value					65,149,000
Accumulated Depreciation					21,663,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,149,000
Balance at end of the year					65,149,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,663,000
Balance at end of year					21,663,000
Southwestern Region | Legacy Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					72,415,000
Initial Costs, Land and Land Improvements					16,882,000
Initial Costs, Buildings and Improvements					100,102,000
Total Initial Acquisition Costs					116,984,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,325,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					17,280,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					107,029,000
Total Carrying Value					124,309,000
Accumulated Depreciation					44,321,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					124,309,000
Balance at end of the year					124,309,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					44,321,000
Balance at end of year					44,321,000
Southwestern Region | DALLAS, TX
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					102,438,000
Initial Costs, Land and Land Improvements					83,453,000
Initial Costs, Buildings and Improvements					153,637,000
Total Initial Acquisition Costs					237,090,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					55,758,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					96,814,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					196,034,000
Total Carrying Value					292,848,000
Accumulated Depreciation					100,146,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					292,848,000
Balance at end of the year					292,848,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					100,146,000
Balance at end of year					100,146,000
Southwestern Region | Barton Creek Landing
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,151,000
Initial Costs, Buildings and Improvements					14,269,000
Total Initial Acquisition Costs					17,420,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					22,118,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,807,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					34,731,000
Total Carrying Value					39,538,000
Accumulated Depreciation					20,260,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,538,000
Balance at end of the year					39,538,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,260,000
Balance at end of year					20,260,000
Southwestern Region | AUSTIN, TX
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,661,000
Initial Costs, Land and Land Improvements					16,417,000
Initial Costs, Buildings and Improvements					104,040,000
Total Initial Acquisition Costs					120,457,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					27,416,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					18,281,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					129,592,000
Total Carrying Value					147,873,000
Accumulated Depreciation					49,305,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					147,873,000
Balance at end of the year					147,873,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					49,305,000
Balance at end of year					49,305,000
United Dominion Reality L.P.
Real Estate and Accumulated Depreciation [Line Items]
Total Carrying Value		4,238,770,000	4,188,480,000	4,182,920,000
Accumulated Depreciation		1,403,303,000	1,241,574,000	1,097,133,000
Aggregate cost for federal income tax purposes		3,600,000,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year		4,188,480,000	4,182,920,000	4,205,298,000
Capital expenditures and development		91,682,000	151,002,000	115,355,000
Real estate sold		-41,013,000	-70,687,000	-116,166,000
Retirement of fully depreciated assets		0	0	-13,945,000
Hurricane related impairment of assets		-379,000	0	-7,622,000
Balance at end of the year		4,238,770,000	4,188,480,000	4,182,920,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year		1,241,574,000	1,097,133,000	976,358,000
Depreciation expense for the year		178,719,000	179,404,000	189,362,000
Accumulated depreciation on sales		-16,674,000	-34,794,000	-54,085,000
Accumulated depreciation on retirements of fully depreciated asset		0	0	-13,945,000
Write off of accumulated depreciation on hurricane related impaired assets		-316,000	0	-557,000
Balance at end of year		1,403,303,000	1,241,574,000	1,097,133,000
United Dominion Reality L.P. | Estimated depreciable lives of buildings range beginning
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for all buildings		35 years
United Dominion Reality L.P. | Estimated depreciable lives of buildings range end
Real Estate and Accumulated Depreciation [Line Items]
Depreciable life for all buildings		55 years
United Dominion Reality L.P. | Los Alisos
Real Estate Owned, Gross [Roll Forward]
Retirement of fully depreciated assets		0	-74,755,000	0
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Accumulated depreciation on retirements of fully depreciated asset		0	-169,000	0
United Dominion Reality L.P. | Other
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0	[2]
Initial Costs, Land and Land Improvements					0	[2]
Initial Costs, Buildings and Improvements					0	[2]
Total Initial Acquisition Costs					0	[2]
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,953,000	[2]
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					0	[2]
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,953,000	[2]
Total Carrying Value					1,953,000	[2]
Accumulated Depreciation					0	[2]
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,953,000	[2]
Balance at end of the year					1,953,000	[2]
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0	[2]
Balance at end of year					0	[2]
United Dominion Reality L.P. | TOTAL CORPORATE
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					0
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					0
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,953,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					0
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,953,000
Total Carrying Value					1,953,000
Accumulated Depreciation					0
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					1,953,000
Balance at end of the year					1,953,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					0
Balance at end of year					0
United Dominion Reality L.P. | Real Estate Under Development | DelRey Tower [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					297,000
Initial Costs, Buildings and Improvements					12,786,000
Total Initial Acquisition Costs					13,083,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					111,790,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,447,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					115,426,000
Total Carrying Value					124,873,000
Accumulated Depreciation					2,382,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					124,873,000
Balance at end of the year					124,873,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,382,000
Balance at end of year					2,382,000
United Dominion Reality L.P. | Commercial Held for Development
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,407,000
Initial Costs, Buildings and Improvements					4,498,000
Total Initial Acquisition Costs					5,905,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,516,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,380,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					6,041,000
Total Carrying Value					7,421,000
Accumulated Depreciation					2,232,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					7,421,000
Balance at end of the year					7,421,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,232,000
Balance at end of year					2,232,000
United Dominion Reality L.P. | Commercial Held for Development | Office Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,407,000
Initial Costs, Buildings and Improvements					4,498,000
Total Initial Acquisition Costs					5,905,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,516,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,380,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					6,041,000
Total Carrying Value					7,421,000
Accumulated Depreciation					2,232,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					7,421,000
Balance at end of the year					7,421,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,232,000
Balance at end of year					2,232,000
United Dominion Reality L.P. | Commercial Held for Development | TOTAL COMMERCIAL & CORPORATE
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,407,000
Initial Costs, Buildings and Improvements					4,498,000
Total Initial Acquisition Costs					5,905,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,469,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,380,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					7,994,000
Total Carrying Value					9,374,000
Accumulated Depreciation					2,232,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					9,374,000
Balance at end of the year					9,374,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					2,232,000
Balance at end of year					2,232,000
United Dominion Reality L.P. | Commercial Held for Development | Total Real Estate Owned
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					931,959,000
Initial Costs, Land and Land Improvements					922,488,000
Initial Costs, Buildings and Improvements					2,469,882,000
Total Initial Acquisition Costs					3,392,370,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					846,400,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,008,014,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					3,230,756,000
Total Carrying Value					4,238,770,000
Accumulated Depreciation					1,403,303,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					4,238,770,000
Balance at end of the year					4,238,770,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					1,403,303,000
Balance at end of year					1,403,303,000
United Dominion Reality L.P. | Western Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					397,387,000
Initial Costs, Land and Land Improvements					578,048,000
Initial Costs, Buildings and Improvements					1,006,929,000
Total Initial Acquisition Costs					1,584,977,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					466,329,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					640,378,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					1,410,928,000
Total Carrying Value					2,051,306,000
Accumulated Depreciation					715,843,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					2,051,306,000
Balance at end of the year					2,051,306,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					715,843,000
Balance at end of year					715,843,000
United Dominion Reality L.P. | Western Region | Harbor at Mesa Verde
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					50,358,000
Initial Costs, Land and Land Improvements					20,476,000
Initial Costs, Buildings and Improvements					28,538,000
Total Initial Acquisition Costs					49,014,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					12,949,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,058,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					40,905,000
Total Carrying Value					61,963,000
Accumulated Depreciation					26,242,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					61,963,000
Balance at end of the year					61,963,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,242,000
Balance at end of year					26,242,000
United Dominion Reality L.P. | Western Region | 27 Seventy FIve Mesa Verde [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,660,000
Initial Costs, Land and Land Improvements					99,329,000
Initial Costs, Buildings and Improvements					110,644,000
Total Initial Acquisition Costs					209,973,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					91,693,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					112,333,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					189,333,000
Total Carrying Value					301,666,000
Accumulated Depreciation					72,689,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					301,666,000
Balance at end of the year					301,666,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					72,689,000
Balance at end of year					72,689,000
United Dominion Reality L.P. | Western Region | Pacific Shores
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					34,112,000
Initial Costs, Land and Land Improvements					7,345,000
Initial Costs, Buildings and Improvements					22,624,000
Total Initial Acquisition Costs					29,969,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,150,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,759,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,360,000
Total Carrying Value					39,119,000
Accumulated Depreciation					19,665,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,119,000
Balance at end of the year					39,119,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,665,000
Balance at end of year					19,665,000
United Dominion Reality L.P. | Western Region | Huntington Vista
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					27,972,000
Initial Costs, Land and Land Improvements					8,055,000
Initial Costs, Buildings and Improvements					22,486,000
Total Initial Acquisition Costs					30,541,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,637,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,438,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,740,000
Total Carrying Value					38,178,000
Accumulated Depreciation					18,655,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					38,178,000
Balance at end of the year					38,178,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,655,000
Balance at end of year					18,655,000
United Dominion Reality L.P. | Western Region | Missions at Back Bay
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					229,000
Initial Costs, Buildings and Improvements					14,129,000
Total Initial Acquisition Costs					14,358,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,133,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,802,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					5,689,000
Total Carrying Value					16,491,000
Accumulated Depreciation					3,994,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,491,000
Balance at end of the year					16,491,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					3,994,000
Balance at end of year					3,994,000
United Dominion Reality L.P. | Western Region | Coronado at Newport b North
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					62,516,000
Initial Costs, Buildings and Improvements					46,082,000
Total Initial Acquisition Costs					108,598,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					24,693,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					66,756,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					66,535,000
Total Carrying Value					133,291,000
Accumulated Depreciation					41,982,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					133,291,000
Balance at end of the year					133,291,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					41,982,000
Balance at end of year					41,982,000
United Dominion Reality L.P. | Western Region | Huntington Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					50,771,000
Initial Costs, Land and Land Improvements					61,535,000
Initial Costs, Buildings and Improvements					18,017,000
Total Initial Acquisition Costs					79,552,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,132,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					62,223,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,461,000
Total Carrying Value					86,684,000
Accumulated Depreciation					16,061,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					86,684,000
Balance at end of the year					86,684,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,061,000
Balance at end of year					16,061,000
United Dominion Reality L.P. | Western Region | Vista Del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,670,000
Initial Costs, Buildings and Improvements					7,080,000
Total Initial Acquisition Costs					17,750,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,062,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,830,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,982,000
Total Carrying Value					19,812,000
Accumulated Depreciation					5,769,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,812,000
Balance at end of the year					19,812,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,769,000
Balance at end of year					5,769,000
United Dominion Reality L.P. | Western Region | Coronado South
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					58,785,000
Initial Costs, Buildings and Improvements					50,067,000
Total Initial Acquisition Costs					108,852,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,875,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					59,277,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					67,450,000
Total Carrying Value					126,727,000
Accumulated Depreciation					40,783,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					126,727,000
Balance at end of the year					126,727,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					40,783,000
Balance at end of year					40,783,000
United Dominion Reality L.P. | Western Region | ORANGE COUNTY, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					193,873,000
Initial Costs, Land and Land Improvements					328,940,000
Initial Costs, Buildings and Improvements					319,667,000
Total Initial Acquisition Costs					648,607,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					175,324,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					359,476,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					464,455,000
Total Carrying Value					823,931,000
Accumulated Depreciation					245,840,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					823,931,000
Balance at end of the year					823,931,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					245,840,000
Balance at end of year					245,840,000
United Dominion Reality L.P. | Western Region | 2000 Post Street
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					9,861,000
Initial Costs, Buildings and Improvements					44,578,000
Total Initial Acquisition Costs					54,439,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,965,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,241,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					53,163,000
Total Carrying Value					63,404,000
Accumulated Depreciation					24,289,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					63,404,000
Balance at end of the year					63,404,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,289,000
Balance at end of year					24,289,000
United Dominion Reality L.P. | Western Region | Birch Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,365,000
Initial Costs, Buildings and Improvements					16,696,000
Total Initial Acquisition Costs					21,061,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,544,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,068,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					22,537,000
Total Carrying Value					27,605,000
Accumulated Depreciation					12,889,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					27,605,000
Balance at end of the year					27,605,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,889,000
Balance at end of year					12,889,000
United Dominion Reality L.P. | Western Region | Highlands Of Marin
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,996,000
Initial Costs, Buildings and Improvements					24,868,000
Total Initial Acquisition Costs					30,864,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					25,720,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,127,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					49,457,000
Total Carrying Value					56,584,000
Accumulated Depreciation					26,904,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					56,584,000
Balance at end of the year					56,584,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,904,000
Balance at end of year					26,904,000
United Dominion Reality L.P. | Western Region | Marina Playa
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,224,000
Initial Costs, Buildings and Improvements					23,916,000
Total Initial Acquisition Costs					30,140,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,482,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,908,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					32,714,000
Total Carrying Value					39,622,000
Accumulated Depreciation					18,351,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,622,000
Balance at end of the year					39,622,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,351,000
Balance at end of year					18,351,000
United Dominion Reality L.P. | Western Region | River Terrace
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,310,000
Initial Costs, Land and Land Improvements					22,161,000
Initial Costs, Buildings and Improvements					40,137,000
Total Initial Acquisition Costs					62,298,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,315,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					22,359,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					43,254,000
Total Carrying Value					65,613,000
Accumulated Depreciation					23,857,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,613,000
Balance at end of the year					65,613,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,857,000
Balance at end of year					23,857,000
United Dominion Reality L.P. | Western Region | CitySouth
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,031,000
Initial Costs, Buildings and Improvements					30,537,000
Total Initial Acquisition Costs					44,568,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					35,190,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,261,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					63,497,000
Total Carrying Value					79,758,000
Accumulated Depreciation					30,810,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					79,758,000
Balance at end of the year					79,758,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					30,810,000
Balance at end of year					30,810,000
United Dominion Reality L.P. | Western Region | Bay Terrace
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,545,000
Initial Costs, Buildings and Improvements					14,458,000
Total Initial Acquisition Costs					23,003,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,571,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,424,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					16,150,000
Total Carrying Value					27,574,000
Accumulated Depreciation					8,710,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					27,574,000
Balance at end of the year					27,574,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,710,000
Balance at end of year					8,710,000
United Dominion Reality L.P. | Western Region | Highlands of Marin Phase II
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,353,000
Initial Costs, Buildings and Improvements					18,559,000
Total Initial Acquisition Costs					23,912,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					11,059,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,753,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					29,218,000
Total Carrying Value					34,971,000
Accumulated Depreciation					13,438,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					34,971,000
Balance at end of the year					34,971,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,438,000
Balance at end of year					13,438,000
United Dominion Reality L.P. | Western Region | Edgewater
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					30,657,000
Initial Costs, Buildings and Improvements					83,872,000
Total Initial Acquisition Costs					114,529,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,261,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					30,687,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					87,103,000
Total Carrying Value					117,790,000
Accumulated Depreciation					34,141,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					117,790,000
Balance at end of the year					117,790,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					34,141,000
Balance at end of year					34,141,000
United Dominion Reality L.P. | Western Region | Almaden Lake Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					27,000,000
Initial Costs, Land and Land Improvements					594,000
Initial Costs, Buildings and Improvements					42,515,000
Total Initial Acquisition Costs					43,109,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,838,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					741,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,206,000
Total Carrying Value					47,947,000
Accumulated Depreciation					18,420,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					47,947,000
Balance at end of the year					47,947,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					18,420,000
Balance at end of year					18,420,000
United Dominion Reality L.P. | Western Region | SAN FRANCISCO, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					66,310,000
Initial Costs, Land and Land Improvements					107,787,000
Initial Costs, Buildings and Improvements					340,136,000
Total Initial Acquisition Costs					447,923,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					112,945,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					116,569,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					444,299,000
Total Carrying Value					560,868,000
Accumulated Depreciation					211,809,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					560,868,000
Balance at end of the year					560,868,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					211,809,000
Balance at end of year					211,809,000
United Dominion Reality L.P. | Western Region | Rosebeach
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					8,414,000
Initial Costs, Buildings and Improvements					17,449,000
Total Initial Acquisition Costs					25,863,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,945,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					8,584,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,224,000
Total Carrying Value					28,808,000
Accumulated Depreciation					11,880,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					28,808,000
Balance at end of the year					28,808,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					11,880,000
Balance at end of year					11,880,000
United Dominion Reality L.P. | Western Region | Ocean Villas
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,135,000
Initial Costs, Buildings and Improvements					12,789,000
Total Initial Acquisition Costs					17,924,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,817,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,326,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,415,000
Total Carrying Value					19,741,000
Accumulated Depreciation					8,442,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,741,000
Balance at end of the year					19,741,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,442,000
Balance at end of year					8,442,000
United Dominion Reality L.P. | Western Region | Other Southern CA [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					46,471,000
Initial Costs, Land and Land Improvements					25,209,000
Initial Costs, Buildings and Improvements					27,152,000
Total Initial Acquisition Costs					52,361,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					57,383,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					35,155,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					74,589,000
Total Carrying Value					109,744,000
Accumulated Depreciation					47,410,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					109,744,000
Balance at end of the year					109,744,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					47,410,000
Balance at end of year					47,410,000
United Dominion Reality L.P. | Western Region | Tierra Del Rey
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,635,000
Initial Costs, Land and Land Improvements					39,586,000
Initial Costs, Buildings and Improvements					36,679,000
Total Initial Acquisition Costs					76,265,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,008,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					39,647,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					39,626,000
Total Carrying Value					79,273,000
Accumulated Depreciation					16,561,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					79,273,000
Balance at end of the year					79,273,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,561,000
Balance at end of year					16,561,000
United Dominion Reality L.P. | Western Region | LOS ANGELES, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,635,000
Initial Costs, Land and Land Improvements					48,000,000
Initial Costs, Buildings and Improvements					54,128,000
Total Initial Acquisition Costs					102,128,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,953,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					48,231,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					59,850,000
Total Carrying Value					108,081,000
Accumulated Depreciation					28,441,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					108,081,000
Balance at end of the year					108,081,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					28,441,000
Balance at end of year					28,441,000
United Dominion Reality L.P. | Western Region | Crowne Pointe
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,486,000
Initial Costs, Buildings and Improvements					6,437,000
Total Initial Acquisition Costs					8,923,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,074,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,822,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,175,000
Total Carrying Value					13,997,000
Accumulated Depreciation					7,069,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,997,000
Balance at end of the year					13,997,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,069,000
Balance at end of year					7,069,000
United Dominion Reality L.P. | Western Region | Hilltop
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,174,000
Initial Costs, Buildings and Improvements					7,408,000
Total Initial Acquisition Costs					9,582,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,722,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,668,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,636,000
Total Carrying Value					13,304,000
Accumulated Depreciation					6,431,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					13,304,000
Balance at end of the year					13,304,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					6,431,000
Balance at end of year					6,431,000
United Dominion Reality L.P. | Western Region | The Kennedy
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,179,000
Initial Costs, Buildings and Improvements					22,307,000
Total Initial Acquisition Costs					28,486,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,742,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,242,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					23,986,000
Total Carrying Value					30,228,000
Accumulated Depreciation					12,640,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,228,000
Balance at end of the year					30,228,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,640,000
Balance at end of year					12,640,000
United Dominion Reality L.P. | Western Region | Hearthstone at Merrill Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					22,957,000
Initial Costs, Land and Land Improvements					6,848,000
Initial Costs, Buildings and Improvements					30,922,000
Total Initial Acquisition Costs					37,770,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,180,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,984,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					33,966,000
Total Carrying Value					40,950,000
Accumulated Depreciation					13,370,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					40,950,000
Balance at end of the year					40,950,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,370,000
Balance at end of year					13,370,000
United Dominion Reality L.P. | Western Region | Island Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					21,284,000
Initial Costs, Buildings and Improvements					89,389,000
Total Initial Acquisition Costs					110,673,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,086,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,413,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					93,346,000
Total Carrying Value					114,759,000
Accumulated Depreciation					34,577,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					114,759,000
Balance at end of the year					114,759,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					34,577,000
Balance at end of year					34,577,000
United Dominion Reality L.P. | Western Region | SEATTLE, WA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					22,957,000
Initial Costs, Land and Land Improvements					38,971,000
Initial Costs, Buildings and Improvements					156,463,000
Total Initial Acquisition Costs					195,434,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,804,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					40,129,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					173,109,000
Total Carrying Value					213,238,000
Accumulated Depreciation					74,087,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					213,238,000
Balance at end of the year					213,238,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					74,087,000
Balance at end of year					74,087,000
United Dominion Reality L.P. | Western Region | Villas at Carlsbad
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,517,000
Initial Costs, Buildings and Improvements					10,718,000
Total Initial Acquisition Costs					17,235,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					2,181,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,763,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					12,653,000
Total Carrying Value					19,416,000
Accumulated Depreciation					7,330,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,416,000
Balance at end of the year					19,416,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,330,000
Balance at end of year					7,330,000
United Dominion Reality L.P. | Western Region | Boronda Manor
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,946,000
Initial Costs, Buildings and Improvements					8,982,000
Total Initial Acquisition Costs					10,928,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,377,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,169,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					17,136,000
Total Carrying Value					20,305,000
Accumulated Depreciation					8,611,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					20,305,000
Balance at end of the year					20,305,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,611,000
Balance at end of year					8,611,000
United Dominion Reality L.P. | Western Region | Garden Court
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					888,000
Initial Costs, Buildings and Improvements					4,188,000
Total Initial Acquisition Costs					5,076,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,304,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,552,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,828,000
Total Carrying Value					10,380,000
Accumulated Depreciation					4,603,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,380,000
Balance at end of the year					10,380,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					4,603,000
Balance at end of year					4,603,000
United Dominion Reality L.P. | Western Region | Cambridge Court
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,039,000
Initial Costs, Buildings and Improvements					12,883,000
Total Initial Acquisition Costs					15,922,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,266,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,274,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,914,000
Total Carrying Value					30,188,000
Accumulated Depreciation					13,065,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					30,188,000
Balance at end of the year					30,188,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,065,000
Balance at end of year					13,065,000
United Dominion Reality L.P. | Western Region | Laurel Tree
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,304,000
Initial Costs, Buildings and Improvements					5,115,000
Total Initial Acquisition Costs					6,419,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,872,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,139,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,152,000
Total Carrying Value					12,291,000
Accumulated Depreciation					5,264,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,291,000
Balance at end of the year					12,291,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,264,000
Balance at end of year					5,264,000
United Dominion Reality L.P. | Western Region | The Pointe At Harden Ranch
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,388,000
Initial Costs, Buildings and Improvements					23,854,000
Total Initial Acquisition Costs					30,242,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					25,703,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,848,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					46,097,000
Total Carrying Value					55,945,000
Accumulated Depreciation					23,292,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					55,945,000
Balance at end of the year					55,945,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					23,292,000
Balance at end of year					23,292,000
United Dominion Reality L.P. | Western Region | The Pointe At Northridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,044,000
Initial Costs, Buildings and Improvements					8,028,000
Total Initial Acquisition Costs					10,072,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,582,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,269,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					16,385,000
Total Carrying Value					19,654,000
Accumulated Depreciation					8,761,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					19,654,000
Balance at end of the year					19,654,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,761,000
Balance at end of year					8,761,000
United Dominion Reality L.P. | Western Region | The Pointe At Westlake
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,329,000
Initial Costs, Buildings and Improvements					5,334,000
Total Initial Acquisition Costs					6,663,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,207,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,154,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					10,716,000
Total Carrying Value					12,870,000
Accumulated Depreciation					5,276,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,870,000
Balance at end of the year					12,870,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,276,000
Balance at end of year					5,276,000
United Dominion Reality L.P. | Western Region | MONTEREY PENINSULA, CA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					16,938,000
Initial Costs, Buildings and Improvements					68,384,000
Total Initial Acquisition Costs					85,322,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					76,311,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					27,405,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					134,228,000
Total Carrying Value					161,633,000
Accumulated Depreciation					68,872,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					161,633,000
Balance at end of the year					161,633,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					68,872,000
Balance at end of year					68,872,000
United Dominion Reality L.P. | Western Region | Verano at Rancho Cucamonga Town Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					46,471,000
Initial Costs, Land and Land Improvements					13,557,000
Initial Costs, Buildings and Improvements					3,645,000
Total Initial Acquisition Costs					17,202,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					53,385,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					23,066,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					47,521,000
Total Carrying Value					70,587,000
Accumulated Depreciation					31,638,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					70,587,000
Balance at end of the year					70,587,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					31,638,000
Balance at end of year					31,638,000
United Dominion Reality L.P. | Western Region | Tualatin Heights
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,273,000
Initial Costs, Buildings and Improvements					9,134,000
Total Initial Acquisition Costs					12,407,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,517,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,839,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					15,085,000
Total Carrying Value					18,924,000
Accumulated Depreciation					9,653,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					18,924,000
Balance at end of the year					18,924,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					9,653,000
Balance at end of year					9,653,000
United Dominion Reality L.P. | Western Region | Andover Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					16,818,000
Initial Costs, Land and Land Improvements					2,916,000
Initial Costs, Buildings and Improvements					16,995,000
Total Initial Acquisition Costs					19,911,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,174,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					3,210,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					24,875,000
Total Carrying Value					28,085,000
Accumulated Depreciation					16,127,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					28,085,000
Balance at end of the year					28,085,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					16,127,000
Balance at end of year					16,127,000
United Dominion Reality L.P. | Western Region | Hunt Club
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					18,323,000
Initial Costs, Land and Land Improvements					6,014,000
Initial Costs, Buildings and Improvements					14,870,000
Total Initial Acquisition Costs					20,884,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,918,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,364,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,438,000
Total Carrying Value					26,802,000
Accumulated Depreciation					13,604,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					26,802,000
Balance at end of the year					26,802,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,604,000
Balance at end of year					13,604,000
United Dominion Reality L.P. | Western Region | PORTLAND, OR
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					35,141,000
Initial Costs, Land and Land Improvements					12,203,000
Initial Costs, Buildings and Improvements					40,999,000
Total Initial Acquisition Costs					53,202,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,609,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					13,413,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					60,398,000
Total Carrying Value					73,811,000
Accumulated Depreciation					39,384,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					73,811,000
Balance at end of the year					73,811,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					39,384,000
Balance at end of year					39,384,000
United Dominion Reality L.P. | Mid Atlantic Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					146,046,000
Initial Costs, Land and Land Improvements					120,584,000
Initial Costs, Buildings and Improvements					515,743,000
Total Initial Acquisition Costs					636,327,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					201,732,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					134,037,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					704,022,000
Total Carrying Value					838,059,000
Accumulated Depreciation					289,227,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					838,059,000
Balance at end of the year					838,059,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					289,227,000
Balance at end of year					289,227,000
United Dominion Reality L.P. | Mid Atlantic Region | The Whitmore
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					6,418,000
Initial Costs, Buildings and Improvements					13,411,000
Total Initial Acquisition Costs					19,829,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					20,350,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					7,493,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					32,686,000
Total Carrying Value					40,179,000
Accumulated Depreciation					21,571,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					40,179,000
Balance at end of the year					40,179,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,571,000
Balance at end of year					21,571,000
United Dominion Reality L.P. | Mid Atlantic Region | Ridgewood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					5,612,000
Initial Costs, Buildings and Improvements					20,086,000
Total Initial Acquisition Costs					25,698,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,108,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					6,012,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					27,794,000
Total Carrying Value					33,806,000
Accumulated Depreciation					19,540,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					33,806,000
Balance at end of the year					33,806,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,540,000
Balance at end of year					19,540,000
United Dominion Reality L.P. | Mid Atlantic Region | Wellington Place at Olde Town
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					32,037,000
Initial Costs, Land and Land Improvements					13,753,000
Initial Costs, Buildings and Improvements					36,059,000
Total Initial Acquisition Costs					49,812,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					17,071,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,650,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					52,233,000
Total Carrying Value					66,883,000
Accumulated Depreciation					32,364,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,883,000
Balance at end of the year					66,883,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					32,364,000
Balance at end of year					32,364,000
United Dominion Reality L.P. | Mid Atlantic Region | Andover House
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					14,357,000
Initial Costs, Buildings and Improvements					51,577,000
Total Initial Acquisition Costs					65,934,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,108,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					14,373,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					54,669,000
Total Carrying Value					69,042,000
Accumulated Depreciation					24,673,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					69,042,000
Balance at end of the year					69,042,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					24,673,000
Balance at end of year					24,673,000
United Dominion Reality L.P. | Mid Atlantic Region | Sullivan Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,137,000
Initial Costs, Buildings and Improvements					103,676,000
Total Initial Acquisition Costs					104,813,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,604,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,373,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					109,044,000
Total Carrying Value					110,417,000
Accumulated Depreciation					44,942,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					110,417,000
Balance at end of the year					110,417,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					44,942,000
Balance at end of year					44,942,000
United Dominion Reality L.P. | Mid Atlantic Region | Circle Towers
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					70,606,000
Initial Costs, Land and Land Improvements					32,815,000
Initial Costs, Buildings and Improvements					107,051,000
Total Initial Acquisition Costs					139,866,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					10,812,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					33,105,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					117,573,000
Total Carrying Value					150,678,000
Accumulated Depreciation					45,360,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					150,678,000
Balance at end of the year					150,678,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					45,360,000
Balance at end of year					45,360,000
United Dominion Reality L.P. | Mid Atlantic Region | Delancey at Shirlington
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					21,606,000
Initial Costs, Buildings and Improvements					66,765,000
Total Initial Acquisition Costs					88,371,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,770,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					21,632,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					68,509,000
Total Carrying Value					90,141,000
Accumulated Depreciation					26,624,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					90,141,000
Balance at end of the year					90,141,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					26,624,000
Balance at end of year					26,624,000
United Dominion Reality L.P. | Mid Atlantic Region | METROPOLITAN DC
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					102,643,000
Initial Costs, Land and Land Improvements					95,995,000
Initial Costs, Buildings and Improvements					411,411,000
Total Initial Acquisition Costs					507,406,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					178,613,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					108,085,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					577,934,000
Total Carrying Value					686,019,000
Accumulated Depreciation					217,456,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					686,019,000
Balance at end of the year					686,019,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					217,456,000
Balance at end of year					217,456,000
United Dominion Reality L.P. | Mid Atlantic Region | Lakeside Mill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					12,569,000
Initial Costs, Land and Land Improvements					2,666,000
Initial Costs, Buildings and Improvements					10,109,000
Total Initial Acquisition Costs					12,775,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,581,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,985,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					14,371,000
Total Carrying Value					17,356,000
Accumulated Depreciation					10,818,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					17,356,000
Balance at end of the year					17,356,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,818,000
Balance at end of year					10,818,000
United Dominion Reality L.P. | Mid Atlantic Region | Tamar Meadow
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,145,000
Initial Costs, Buildings and Improvements					17,150,000
Total Initial Acquisition Costs					21,295,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,089,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,577,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					21,807,000
Total Carrying Value					26,384,000
Accumulated Depreciation					14,882,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					26,384,000
Balance at end of the year					26,384,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					14,882,000
Balance at end of year					14,882,000
United Dominion Reality L.P. | Mid Atlantic Region | Calvertbs Walk
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,408,000
Initial Costs, Buildings and Improvements					24,692,000
Total Initial Acquisition Costs					29,100,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,766,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,726,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,140,000
Total Carrying Value					35,866,000
Accumulated Depreciation					19,763,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,866,000
Balance at end of the year					35,866,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					19,763,000
Balance at end of year					19,763,000
United Dominion Reality L.P. | Mid Atlantic Region | Liriope Apartments
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,620,000
Initial Costs, Buildings and Improvements					6,791,000
Total Initial Acquisition Costs					8,411,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					1,250,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,646,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					8,015,000
Total Carrying Value					9,661,000
Accumulated Depreciation					5,090,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					9,661,000
Balance at end of the year					9,661,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					5,090,000
Balance at end of year					5,090,000
United Dominion Reality L.P. | Mid Atlantic Region | 20 Lambourne
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,834,000
Initial Costs, Land and Land Improvements					11,750,000
Initial Costs, Buildings and Improvements					45,590,000
Total Initial Acquisition Costs					57,340,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					5,433,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					12,018,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					50,755,000
Total Carrying Value					62,773,000
Accumulated Depreciation					21,218,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					62,773,000
Balance at end of the year					62,773,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,218,000
Balance at end of year					21,218,000
United Dominion Reality L.P. | Mid Atlantic Region | BALTIMORE, MD
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					43,403,000
Initial Costs, Land and Land Improvements					24,589,000
Initial Costs, Buildings and Improvements					104,332,000
Total Initial Acquisition Costs					128,921,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					23,119,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					25,952,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					126,088,000
Total Carrying Value					152,040,000
Accumulated Depreciation					71,771,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					152,040,000
Balance at end of the year					152,040,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					71,771,000
Balance at end of year					71,771,000
United Dominion Reality L.P. | Southeastern Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					47,572,000
Initial Costs, Buildings and Improvements					170,881,000
Total Initial Acquisition Costs					218,453,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					114,976,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					56,296,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					277,133,000
Total Carrying Value					333,429,000
Accumulated Depreciation					179,254,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					333,429,000
Balance at end of the year					333,429,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					179,254,000
Balance at end of year					179,254,000
United Dominion Reality L.P. | Southeastern Region | Sugar Mill Creek
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,242,000
Initial Costs, Buildings and Improvements					7,553,000
Total Initial Acquisition Costs					9,795,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,846,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,734,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,907,000
Total Carrying Value					16,641,000
Accumulated Depreciation					8,998,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					16,641,000
Balance at end of the year					16,641,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					8,998,000
Balance at end of year					8,998,000
United Dominion Reality L.P. | Southeastern Region | Inlet Bay
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					7,702,000
Initial Costs, Buildings and Improvements					23,150,000
Total Initial Acquisition Costs					30,852,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,657,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					9,211,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					36,298,000
Total Carrying Value					45,509,000
Accumulated Depreciation					25,585,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					45,509,000
Balance at end of the year					45,509,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					25,585,000
Balance at end of year					25,585,000
United Dominion Reality L.P. | Southeastern Region | MacAlpine Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,869,000
Initial Costs, Buildings and Improvements					36,858,000
Total Initial Acquisition Costs					47,727,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,384,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					11,408,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					43,703,000
Total Carrying Value					55,111,000
Accumulated Depreciation					27,162,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					55,111,000
Balance at end of the year					55,111,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					27,162,000
Balance at end of year					27,162,000
United Dominion Reality L.P. | Southeastern Region | TAMPA, FL
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					20,813,000
Initial Costs, Buildings and Improvements					67,561,000
Total Initial Acquisition Costs					88,374,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					28,887,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					23,353,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					93,908,000
Total Carrying Value					117,261,000
Accumulated Depreciation					61,745,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					117,261,000
Balance at end of the year					117,261,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					61,745,000
Balance at end of year					61,745,000
United Dominion Reality L.P. | Southeastern Region | Legacy Hill
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,148,000
Initial Costs, Buildings and Improvements					5,867,000
Total Initial Acquisition Costs					7,015,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,636,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,762,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					13,889,000
Total Carrying Value					15,651,000
Accumulated Depreciation					10,830,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					15,651,000
Balance at end of the year					15,651,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					10,830,000
Balance at end of year					10,830,000
United Dominion Reality L.P. | Southeastern Region | Hickory Run
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					1,469,000
Initial Costs, Buildings and Improvements					11,584,000
Total Initial Acquisition Costs					13,053,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					9,761,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					2,139,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					20,675,000
Total Carrying Value					22,814,000
Accumulated Depreciation					13,482,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					22,814,000
Balance at end of the year					22,814,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					13,482,000
Balance at end of year					13,482,000
United Dominion Reality L.P. | Southeastern Region | Carrington Hills
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					2,117,000
Initial Costs, Buildings and Improvements					0
Total Initial Acquisition Costs					2,117,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					33,846,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,462,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,501,000
Total Carrying Value					35,963,000
Accumulated Depreciation					20,064,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					35,963,000
Balance at end of the year					35,963,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,064,000
Balance at end of year					20,064,000
United Dominion Reality L.P. | Southeastern Region | Brookridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					708,000
Initial Costs, Buildings and Improvements					5,461,000
Total Initial Acquisition Costs					6,169,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,500,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,143,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					9,526,000
Total Carrying Value					10,669,000
Accumulated Depreciation					6,641,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					10,669,000
Balance at end of the year					10,669,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					6,641,000
Balance at end of year					6,641,000
United Dominion Reality L.P. | Southeastern Region | Breckenridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					766,000
Initial Costs, Buildings and Improvements					7,714,000
Total Initial Acquisition Costs					8,480,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,357,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					1,258,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					11,579,000
Total Carrying Value					12,837,000
Accumulated Depreciation					7,704,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					12,837,000
Balance at end of the year					12,837,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					7,704,000
Balance at end of year					7,704,000
United Dominion Reality L.P. | Southeastern Region | Polo Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					4,583,000
Initial Costs, Buildings and Improvements					16,293,000
Total Initial Acquisition Costs					20,876,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					16,042,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					5,643,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					31,275,000
Total Carrying Value					36,918,000
Accumulated Depreciation					20,471,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					36,918,000
Balance at end of the year					36,918,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,471,000
Balance at end of year					20,471,000
United Dominion Reality L.P. | Southeastern Region | NASHVILLE, TN
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,791,000
Initial Costs, Buildings and Improvements					46,919,000
Total Initial Acquisition Costs					57,710,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					77,142,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,407,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					118,445,000
Total Carrying Value					134,852,000
Accumulated Depreciation					79,192,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					134,852,000
Balance at end of the year					134,852,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					79,192,000
Balance at end of year					79,192,000
United Dominion Reality L.P. | Southeastern Region | The Reserve and Park at Riverbridge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					15,968,000
Initial Costs, Buildings and Improvements					56,401,000
Total Initial Acquisition Costs					72,369,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,947,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,536,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					64,780,000
Total Carrying Value					81,316,000
Accumulated Depreciation					38,317,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					81,316,000
Balance at end of the year					81,316,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,317,000
Balance at end of year					38,317,000
United Dominion Reality L.P. | Southeastern Region | OTHER FLORIDA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					39,179,000
Initial Costs, Land and Land Improvements					15,968,000
Initial Costs, Buildings and Improvements					56,401,000
Total Initial Acquisition Costs					72,369,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,947,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					16,536,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					64,780,000
Total Carrying Value					81,316,000
Accumulated Depreciation					38,317,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					81,316,000
Balance at end of the year					81,316,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					38,317,000
Balance at end of year					38,317,000
United Dominion Reality L.P. | Northeast Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					246,909,000
Initial Costs, Land and Land Improvements					130,808,000
Initial Costs, Buildings and Improvements					624,509,000
Total Initial Acquisition Costs					755,317,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					22,289,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					129,525,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					648,081,000
Total Carrying Value					777,606,000
Accumulated Depreciation					130,503,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					777,606,000
Balance at end of the year					777,606,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					130,503,000
Balance at end of year					130,503,000
United Dominion Reality L.P. | Northeast Region | Inwood West
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					56,447,000
Initial Costs, Land and Land Improvements					20,778,000
Initial Costs, Buildings and Improvements					88,096,000
Total Initial Acquisition Costs					108,874,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					3,034,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					19,309,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					92,599,000
Total Carrying Value					111,908,000
Accumulated Depreciation					20,102,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					111,908,000
Balance at end of the year					111,908,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,102,000
Balance at end of year					20,102,000
United Dominion Reality L.P. | Northeast Region | 14 North
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					10,961,000
Initial Costs, Buildings and Improvements					51,175,000
Total Initial Acquisition Costs					62,136,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					4,563,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					10,999,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					55,700,000
Total Carrying Value					66,699,000
Accumulated Depreciation					12,750,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					66,699,000
Balance at end of the year					66,699,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					12,750,000
Balance at end of year					12,750,000
United Dominion Reality L.P. | Northeast Region | BOSTON, MA
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					56,447,000
Initial Costs, Land and Land Improvements					31,739,000
Initial Costs, Buildings and Improvements					139,271,000
Total Initial Acquisition Costs					171,010,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,597,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					30,308,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					148,299,000
Total Carrying Value					178,607,000
Accumulated Depreciation					32,852,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					178,607,000
Balance at end of the year					178,607,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					32,852,000
Balance at end of year					32,852,000
United Dominion Reality L.P. | Northeast Region | 10 Hanover Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					190,462,000
Initial Costs, Land and Land Improvements					41,432,000
Initial Costs, Buildings and Improvements					218,983,000
Total Initial Acquisition Costs					260,415,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,396,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					41,481,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					227,330,000
Total Carrying Value					268,811,000
Accumulated Depreciation					42,678,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					268,811,000
Balance at end of the year					268,811,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					42,678,000
Balance at end of year					42,678,000
United Dominion Reality L.P. | Northeast Region | 95 Wall Street
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					57,637,000
Initial Costs, Buildings and Improvements					266,255,000
Total Initial Acquisition Costs					323,892,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					6,296,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					57,736,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					272,452,000
Total Carrying Value					330,188,000
Accumulated Depreciation					54,973,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					330,188,000
Balance at end of the year					330,188,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					54,973,000
Balance at end of year					54,973,000
United Dominion Reality L.P. | Northeast Region | NEW YORK, NY
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					190,462,000
Initial Costs, Land and Land Improvements					99,069,000
Initial Costs, Buildings and Improvements					485,238,000
Total Initial Acquisition Costs					584,307,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					14,692,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					99,217,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					499,782,000
Total Carrying Value					598,999,000
Accumulated Depreciation					97,651,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					598,999,000
Balance at end of the year					598,999,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					97,651,000
Balance at end of year					97,651,000
United Dominion Reality L.P. | Southwestern Region
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					102,438,000
Initial Costs, Land and Land Improvements					44,069,000
Initial Costs, Buildings and Improvements					147,322,000
Total Initial Acquisition Costs					191,391,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					37,605,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					46,398,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					182,598,000
Total Carrying Value					228,996,000
Accumulated Depreciation					86,244,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					228,996,000
Balance at end of the year					228,996,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					86,244,000
Balance at end of year					86,244,000
United Dominion Reality L.P. | Southwestern Region | THIRTY377
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					30,023,000
Initial Costs, Land and Land Improvements					24,036,000
Initial Costs, Buildings and Improvements					32,951,000
Total Initial Acquisition Costs					56,987,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					8,162,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					24,311,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					40,838,000
Total Carrying Value					65,149,000
Accumulated Depreciation					21,663,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					65,149,000
Balance at end of the year					65,149,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					21,663,000
Balance at end of year					21,663,000
United Dominion Reality L.P. | Southwestern Region | Legacy Village
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					72,415,000
Initial Costs, Land and Land Improvements					16,882,000
Initial Costs, Buildings and Improvements					100,102,000
Total Initial Acquisition Costs					116,984,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					7,325,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					17,280,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					107,029,000
Total Carrying Value					124,309,000
Accumulated Depreciation					44,321,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					124,309,000
Balance at end of the year					124,309,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					44,321,000
Balance at end of year					44,321,000
United Dominion Reality L.P. | Southwestern Region | DALLAS, TX
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					102,438,000
Initial Costs, Land and Land Improvements					40,918,000
Initial Costs, Buildings and Improvements					133,053,000
Total Initial Acquisition Costs					173,971,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					15,487,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					41,591,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					147,867,000
Total Carrying Value					189,458,000
Accumulated Depreciation					65,984,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					189,458,000
Balance at end of the year					189,458,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					65,984,000
Balance at end of year					65,984,000
United Dominion Reality L.P. | Southwestern Region | Barton Creek Landing
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,151,000
Initial Costs, Buildings and Improvements					14,269,000
Total Initial Acquisition Costs					17,420,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					22,118,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,807,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					34,731,000
Total Carrying Value					39,538,000
Accumulated Depreciation					20,260,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,538,000
Balance at end of the year					39,538,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,260,000
Balance at end of year					20,260,000
United Dominion Reality L.P. | Southwestern Region | AUSTIN, TX
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances					0
Initial Costs, Land and Land Improvements					3,151,000
Initial Costs, Buildings and Improvements					14,269,000
Total Initial Acquisition Costs					17,420,000
Costs of Improvements Capitalized Subsequent to Acquisition Costs					22,118,000
Gross Amount at Which Carried at Close of Period, Land and Land Improvements					4,807,000
Gross Amount at Which Carried at Close of Period, Buildings & Buildings Improvements					34,731,000
Total Carrying Value					39,538,000
Accumulated Depreciation					20,260,000
Real Estate Owned, Gross [Roll Forward]
Balance at beginning of the year					39,538,000
Balance at end of the year					39,538,000
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Balance at beginning of the year					20,260,000
Balance at end of year					20,260,000
Corporate Joint Venture [Member]
Real Estate Owned, Gross [Roll Forward]
Real estate acquired		0	129,437,000	0
Retirement of fully depreciated assets		-112,344,000	-356,303,000	0
Real Estate Owned, Accumulated Depreciation [Roll Forward]
Accumulated depreciation on retirements of fully depreciated asset		($4,228,000)	($20,662,000)	$0
[1]	Includes unallocated accruals and capital expenditures.The aggregate cost for federal income tax purposes was approximately $7.7 billion at December 31, 2014. The estimated depreciable lives for all buildings in the latest Consolidated Statements of Operations are 35 to 55 years.
[2]	Includes unallocated accruals and capital expenditures.The aggregate cost for federal income tax purpose was approximately $3.6 billion at December 31, 2011.

IncomeLoss_Per_Share_UNITED_DO3

Income/(Loss) Per Share (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	3 Months Ended												12 Months Ended			9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest													($5,511)	$48	$2,089
Income (Loss) from Continuing Operations Attributable to Parent													154,324	2,448	-44,356
Income/(loss) from discontinued operations	0		79		18		-87		41,376	884	829	853	10	43,942	266,608
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest													159,842	46,282	220,303
Comprehensive (Income) Loss, Net of Tax, Attributable to Noncontrolling Interest													5,375	1,720	8,206
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest													0	-1,578	-10,075
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent													10	42,364	256,533
United Dominion Reality L.P.
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income (Loss) from Continuing Operations Attributable to Parent													96,227	28,652	-13,409
Income/(loss) from discontinued operations									42,407		882	905	0	45,176	57,643	982
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest													97,179	77,942	44,334
Comprehensive (Income) Loss, Net of Tax, Attributable to Noncontrolling Interest													952	4,566	352
Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted													183,279	184,196	184,281
Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership and General Partnership Unit, Basic and Diluted, Net of Tax													$0.53	$0.16	($0.07)
Income (Loss) from Discontinued Operations, Net of Tax, Per Outstanding Limited Partnership and General Partnership Unit, Basic and Diluted													$0	$0.24	$0.31
Net Income (Loss), Per Outstanding Limited Partnership and General Partnership Unit, Basic and Diluted, Net of Tax	$0.18	[1]	$0.05	[1]	$0.13	[1]	$0.17	[1]	$0.24		$0.06	$0.04	$0.53	$0.40	$0.24	$0.06
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest													0	-452	-252
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent													0	44,724	57,391
Noncontrolling Interest
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest													3	60	-140
Noncontrolling Interest | United Dominion Reality L.P.
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest													($952)	($4,114)	($100)
[1]	Quarterly income/(loss) per OP Unit amounts may not total to the annual amounts