Erp Operating LTD Partnership 10-Q 1 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Oct. 27, 2017
Document And Entity Information [Line Items]
Entity Registrant Name	EQUITY RESIDENTIAL
Entity Central Index Key	906,107
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Trading Symbol	EQR
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		367,484,786
ERPOP [Member]
Document And Entity Information [Line Items]
Entity Registrant Name	ERP OPERATING LIMITED PARTNERSHIP
Entity Central Index Key	931,182
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer

CONSOLIDATED BALANCE SHEETS (Un

CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Investment in real estate
Land	$ 5,985,004	$ 5,899,862
Depreciable property	19,571,402	18,730,579
Projects under development	293,064	637,168
Land held for development	99,073	118,816
Investment in real estate	25,948,543	25,386,425
Accumulated depreciation	(5,849,110)	(5,360,389)
Investment in real estate, net	20,099,433	20,026,036
Cash and cash equivalents	46,565	77,207
Investments in unconsolidated entities	59,029	60,141
Deposits – restricted	36,639	76,946
Escrow deposits – mortgage	10,972	64,935
Other assets	445,195	398,883
Total assets	20,697,833	20,704,148
Liabilities:
Mortgage notes payable, net	3,619,180	4,119,181
Notes, net	5,143,248	4,848,079
Line of credit and commercial paper	229,844	19,998
Accounts payable and accrued expenses	167,984	147,482
Accrued interest payable	72,811	60,946
Other liabilities	332,650	350,466
Security deposits	65,230	62,624
Distributions payable	192,569	192,296
Total liabilities	9,823,516	9,801,072
Commitments and contingencies
Redeemable Noncontrolling Interests – Operating Partnership	380,541	442,092
Shareholders' equity:
Preferred Shares of beneficial interest, $0.01 par value; 100,000,000 shares authorized; 745,600 shares issued and outstanding as of September 30, 2017 and December 31, 2016	37,280	37,280
Common Shares of beneficial interest, $0.01 par value; 1,000,000,000 shares authorized; 367,462,480 shares issued and outstanding as of September 30, 2017 and 365,870,924 shares issued and outstanding as of December 31, 2016	3,675	3,659
Paid in capital	8,848,739	8,758,422
Retained earnings	1,464,249	1,543,626
Accumulated other comprehensive (loss)	(94,674)	(113,909)
Total shareholders’ equity	10,259,269	10,229,078
Noncontrolling Interests:
Operating Partnership	228,332	221,297
Partially Owned Properties	6,175	10,609
Total Noncontrolling Interests	234,507	231,906
Total equity	10,493,776	10,460,984
Total liabilities and equity/capital	$ 20,697,833	$ 20,704,148

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (Unaudited) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	100,000,000	100,000,000
Preferred Stock, Shares Issued	745,600	745,600
Preferred Stock, Shares Outstanding	745,600	745,600
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	1,000,000,000	1,000,000,000
Common Stock, Shares, Issued	367,462,480	365,870,924
Common Stock, Shares, Outstanding	367,462,480	365,870,924

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
REVENUES
Rental income	$ 623,951	$ 605,856	$ 1,840,170	$ 1,816,960
Fee and asset management	171	218	532	3,351
Total revenues	624,122	606,074	1,840,702	1,820,311
EXPENSES
Property and maintenance	104,721	104,216	306,645	309,688
Real estate taxes and insurance	84,087	81,343	253,318	238,954
Property management	20,861	19,517	64,702	64,003
General and administrative	12,567	12,395	40,366	47,408
Depreciation	184,100	179,230	542,964	528,242
Total expenses	406,336	396,701	1,207,995	1,188,295
Operating income	217,786	209,373	632,707	632,016
Interest and other income	3,945	5,509	5,708	65,092
Other expenses	(1,028)	(10,420)	(3,160)	(14,480)
Interest:
Expense incurred, net	(91,145)	(86,352)	(288,579)	(386,316)
Amortization of deferred financing costs	(2,064)	(2,261)	(6,447)	(10,000)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations	127,494	115,849	340,229	286,312
Income and other tax (expense) benefit	(228)	(426)	(710)	(1,189)
(Loss) income from investments in unconsolidated entities	(398)	7,750	(2,153)	5,846
Net gain on sales of real estate properties	17,328	90,036	141,761	3,870,871
Net gain on sales of land parcels		4,037	19,170	15,759
Income from continuing operations	144,196	217,246	498,297	4,177,599
Discontinued operations, net	0	246	0	124
Net income	144,196	217,492	498,297	4,177,723
Net (income) attributable to Noncontrolling Interests:
Operating Partnership	(5,166)	(8,353)	(17,931)	(160,442)
Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Net income attributable to controlling interests	138,229	208,316	478,012	4,014,913
Preferred distributions	(772)	(773)	(2,318)	(2,318)
Net income available to Common Shares	$ 137,457	$ 207,543	$ 475,694	$ 4,012,595
Earnings per share – basic:
Income from continuing operations available to Common Shares	$ 0.37	$ 0.57	$ 1.30	$ 11
Net income available to Common Shares	$ 0.37	$ 0.57	$ 1.30	$ 11
Weighted average Common Shares outstanding	366,996	365,109	366,809	364,917
Earnings per share – diluted:
Income from continuing operations available to Common Shares	$ 0.37	$ 0.56	$ 1.29	$ 10.92
Net income available to Common Shares	$ 0.37	$ 0.56	$ 1.29	$ 10.92
Weighted average Common Shares outstanding	382,945	382,373	382,640	382,284
Distributions declared per Common Share outstanding	$ 0.50375	$ 3.50375	$ 1.51125	$ 12.51125

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Comprehensive income
Net income	$ 144,196	$ 217,492	$ 498,297	$ 4,177,723
Other comprehensive income (loss) – derivative instruments:
Unrealized holding gains (losses) arising during the period	1,709	227	5,216	(4,240)
Losses reclassified into earnings from other comprehensive income	4,768	4,340	14,019	37,262
Other comprehensive income (loss) – foreign currency:
Currency translation adjustments arising during the period		214		264
Other comprehensive income	6,477	4,781	19,235	33,286
Comprehensive income	150,673	222,273	517,532	4,211,009
Comprehensive (income) attributable to Noncontrolling Interests	(6,201)	(9,362)	(20,983)	(164,096)
Comprehensive income attributable to controlling interests	$ 144,472	$ 212,911	$ 496,549	$ 4,046,913

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 498,297	$ 4,177,723
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	542,964	528,242
Amortization of deferred financing costs	6,447	10,000
Amortization of above/below market lease intangibles	2,729	2,566
Amortization of discounts and premiums on debt	4,939	(18,328)
Amortization of deferred settlements on derivative instruments	14,010	37,187
Write-off of pursuit costs	2,329	3,379
Loss (income) from investments in unconsolidated entities	2,153	(5,846)
Distributions from unconsolidated entities – return on capital	2,031	2,165
Net (gain) on sales of investment securities and other investments		(58,416)
Net (gain) on sales of real estate properties	(141,761)	(3,870,871)
Net (gain) on sales of land parcels	(19,170)	(15,759)
Net (gain) on sales of discontinued operations		(43)
Compensation paid with Company Common Shares	19,999	25,540
Changes in assets and liabilities:
Decrease in deposits – restricted	788	9,992
Decrease in mortgage deposits	1,447	222
(Increase) decrease in other assets	(23,024)	4,248
Increase in accounts payable and accrued expenses	62,635	41,371
Increase (decrease) in accrued interest payable	11,865	(15,780)
(Decrease) in other liabilities	(28,250)	(24,749)
Increase (decrease) in security deposits	2,606	(13,522)
Net cash provided by operating activities	963,034	819,321
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(466,395)	(205,881)
Investment in real estate – development/other	(227,187)	(454,502)
Capital expenditures to real estate	(143,258)	(124,551)
Non-real estate capital additions	(776)	(4,467)
Interest capitalized for real estate under development	(23,164)	(41,658)
Proceeds from disposition of real estate, net	350,000	6,584,126
Investments in unconsolidated entities	(5,324)	(3,826)
Distributions from unconsolidated entities – return of capital	329	13,798
Proceeds from sale of investment securities and other investments		72,815
Decrease (increase) in deposits on real estate acquisitions and investments, net	39,519	(83,668)
(Increase) in mortgage deposits	(4,541)	(21)
Net cash (used for) provided by investing activities	(480,797)	5,752,165
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(6,272)	(507)
Mortgage deposits	57,057	(6,249)
Mortgage notes payable, net:
Lump sum payoffs	(493,420)	(565,084)
Scheduled principal repayments	(8,771)	(6,644)
Notes, net:
Proceeds	692,466
Lump sum payoffs	(394,077)	(1,500,000)
Line of credit and commercial paper:
Line of credit proceeds	1,845,000	246,000
Line of credit repayments	(1,845,000)	(246,000)
Commercial paper proceeds	3,888,675	1,324,784
Commercial paper repayments	(3,681,750)	(1,712,472)
Proceeds from settlement of derivative instruments	1,296
Proceeds from Employee Share Purchase Plan (ESPP)	2,963	2,778
Proceeds from exercise of options	12,967	26,939
Payment of offering costs	(36)	(304)
Other financing activities, net	(40)	(33)
Contributions – Noncontrolling Interests – Partially Owned Properties	125
Contributions – Noncontrolling Interests – Operating Partnership		1
Distributions:
Common Shares	(554,267)	(3,490,838)
Preferred Shares	(2,318)	(2,318)
Noncontrolling Interests – Operating Partnership	(20,604)	(137,641)
Noncontrolling Interests – Partially Owned Properties	(6,873)	(28,588)
Net cash (used for) financing activities	(512,879)	(6,096,176)
Net (decrease) increase in cash and cash equivalents	(30,642)	475,310
Cash and cash equivalents, beginning of period	77,207	42,276
Cash and cash equivalents, end of period	46,565	517,586
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	257,805	383,374
Net cash paid for income and other taxes	964	1,333
Real estate acquisitions/dispositions/other:
Mortgage loans assumed		43,400
Amortization of deferred financing costs:
Other assets	1,810	2,291
Mortgage notes payable, net	1,943	3,320
Notes, net	2,694	4,389
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	247	(21,318)
Notes, net	1,771	2,578
Line of credit and commercial paper	2,921	412
Amortization of deferred settlements on derivative instruments:
Other liabilities	(9)	(75)
Accumulated other comprehensive income	14,019	37,262
Write-off of pursuit costs:
Investment in real estate, net	2,292	2,876
Other assets	17	399
Accounts payable and accrued expenses	20	104
Loss (income) from investments in unconsolidated entities:
Investments in unconsolidated entities	1,076	(6,999)
Other liabilities	1,077	1,153
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(3,803)	(4,563)
Notes, net	(1,413)	4,563
Other liabilities		4,240
Accumulated other comprehensive income	5,216	(4,240)
Investments in unconsolidated entities:
Investments in unconsolidated entities	(2,324)	(1,726)
Other liabilities	(3,000)	(2,100)
Distributions from unconsolidated entities - return of capital:
Investments in unconsolidated entities	329	14,014
Other assets		(216)
Debt financing costs:
Mortgage notes payable, net		(507)
Notes, net	$ (6,272)
Other:
Foreign currency translation adjustments		$ (264)

CONSOLIDATED STATEMENT OF CHANG

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Total	PREFERRED SHARES	COMMON SHARES, $0.01 PAR VALUE	PAID IN CAPITAL	RETAINED EARNINGS	ACCUMULATED OTHER COMPREHENSIVE (LOSS)	OPERATING PARTNERSHIP	PARTIALLY OWNED PROPERTIES
Balance, beginning of year at Dec. 31, 2016	$ 10,229,078	$ 37,280	$ 3,659	$ 8,758,422	$ 1,543,626	$ (113,909)
Balance, beginning of year at Dec. 31, 2016	231,906						$ 221,297	$ 10,609
COMMON SHARES, $0.01 PAR VALUE
Conversion of OP Units into Common Shares			11	14,706			(14,717)
Exercise of share options			3	12,964
Employee Share Purchase Plan (ESPP)			1	2,962
Restricted shares			1	7,488
Share options				6,384
ESPP discount				586
PAID IN CAPITAL
Conversion of OP Units into Common Shares			11	14,706			(14,717)
Exercise of share options			3	12,964
Employee Share Purchase Plan (ESPP)			1	2,962
Share-based employee compensation expense
Offering costs				(36)
Supplemental Executive Retirement Plan (SERP)				(594)
Change in market value of Redeemable Noncontrolling Interests – Operating Partnership	(29,551)			29,551
Adjustment for Noncontrolling Interests ownership in Operating Partnership				16,306			(16,306)
RETAINED EARNINGS
Net income attributable to controlling interests	478,012				478,012
Common Share distributions					(555,071)
Preferred Share distributions					(2,318)
Accumulated other comprehensive income – derivative instruments:
Unrealized holding gains (losses) arising during the period	5,216					5,216
Losses reclassified into earnings from other comprehensive income	(14,019)					14,019
OPERATING PARTNERSHIP
Conversion of OP Units into Common Shares			11	14,706			(14,717)
Equity compensation associated with Noncontrolling Interests							8,200
Net income	498,297
Distributions to Noncontrolling Interests							(20,073)	(6,913)
Change in carrying value of Redeemable Noncontrolling Interests - Operating Partnership	(32,000)						32,000
Adjustment for Noncontrolling Interests ownership in Operating Partnership				16,306			(16,306)
Net income attributable to Noncontrolling Interests	17,931						17,931	2,354
PARTIALLY OWNED PROPERTIES
Net income	498,297
Distributions to Noncontrolling Interests							(20,073)	(6,913)
Net income attributable to Noncontrolling Interests	17,931						17,931	2,354
Contributions – Noncontrolling Interests – Partially Owned Properties	125							125
Balance, end of period at Sep. 30, 2017	10,259,269	$ 37,280	$ 3,675	$ 8,848,739	$ 1,464,249	$ (94,674)
Balance, end of period at Sep. 30, 2017	$ 234,507						$ 228,332	$ 6,175

CONSOLIDATED BALANCE SHEETS OF

CONSOLIDATED BALANCE SHEETS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Investment in real estate
Land	$ 5,985,004	$ 5,899,862
Depreciable property	19,571,402	18,730,579
Projects under development	293,064	637,168
Land held for development	99,073	118,816
Investment in real estate	25,948,543	25,386,425
Accumulated depreciation	(5,849,110)	(5,360,389)
Investment in real estate, net	20,099,433	20,026,036
Cash and cash equivalents	46,565	77,207
Investments in unconsolidated entities	59,029	60,141
Deposits – restricted	36,639	76,946
Escrow deposits – mortgage	10,972	64,935
Other assets	445,195	398,883
Total assets	20,697,833	20,704,148
Liabilities:
Mortgage notes payable, net	3,619,180	4,119,181
Notes, net	5,143,248	4,848,079
Line of credit and commercial paper	229,844	19,998
Accounts payable and accrued expenses	167,984	147,482
Accrued interest payable	72,811	60,946
Other liabilities	332,650	350,466
Security deposits	65,230	62,624
Distributions payable	192,569	192,296
Total liabilities	9,823,516	9,801,072
Commitments and contingencies
Partners' Capital:
Accumulated other comprehensive (loss)	(94,674)	(113,909)
Noncontrolling Interests – Partially Owned Properties	6,175	10,609
Total liabilities and equity/capital	20,697,833	20,704,148
ERPOP [Member]
Investment in real estate
Land	5,985,004	5,899,862
Depreciable property	19,571,402	18,730,579
Projects under development	293,064	637,168
Land held for development	99,073	118,816
Investment in real estate	25,948,543	25,386,425
Accumulated depreciation	(5,849,110)	(5,360,389)
Investment in real estate, net	20,099,433	20,026,036
Cash and cash equivalents	46,565	77,207
Investments in unconsolidated entities	59,029	60,141
Deposits – restricted	36,639	76,946
Escrow deposits – mortgage	10,972	64,935
Other assets	445,195	398,883
Total assets	20,697,833	20,704,148
Liabilities:
Mortgage notes payable, net	3,619,180	4,119,181
Notes, net	5,143,248	4,848,079
Line of credit and commercial paper	229,844	19,998
Accounts payable and accrued expenses	167,984	147,482
Accrued interest payable	72,811	60,946
Other liabilities	332,650	350,466
Security deposits	65,230	62,624
Distributions payable	192,569	192,296
Total liabilities	9,823,516	9,801,072
Commitments and contingencies
Redeemable Limited Partners	380,541	442,092
Partners' Capital:
Preference Units	37,280	37,280
General Partner	10,316,663	10,305,707
Limited Partners	228,332	221,297
Accumulated other comprehensive (loss)	(94,674)	(113,909)
Total partners' capital	10,487,601	10,450,375
Noncontrolling Interests – Partially Owned Properties	6,175	10,609
Total capital	10,493,776	10,460,984
Total liabilities and equity/capital	$ 20,697,833	$ 20,704,148

CONSOLIDATED STATEMENTS OF OPE9

CONSOLIDATED STATEMENTS OF OPERATIONS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
REVENUES
Rental income	$ 623,951	$ 605,856	$ 1,840,170	$ 1,816,960
Fee and asset management	171	218	532	3,351
Total revenues	624,122	606,074	1,840,702	1,820,311
EXPENSES
Property and maintenance	104,721	104,216	306,645	309,688
Real estate taxes and insurance	84,087	81,343	253,318	238,954
Property management	20,861	19,517	64,702	64,003
General and administrative	12,567	12,395	40,366	47,408
Depreciation	184,100	179,230	542,964	528,242
Total expenses	406,336	396,701	1,207,995	1,188,295
Operating income	217,786	209,373	632,707	632,016
Interest and other income	3,945	5,509	5,708	65,092
Other expenses	(1,028)	(10,420)	(3,160)	(14,480)
Interest:
Expense incurred, net	(91,145)	(86,352)	(288,579)	(386,316)
Amortization of deferred financing costs	(2,064)	(2,261)	(6,447)	(10,000)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations	127,494	115,849	340,229	286,312
Income and other tax (expense) benefit	(228)	(426)	(710)	(1,189)
(Loss) income from investments in unconsolidated entities	(398)	7,750	(2,153)	5,846
Net gain on sales of real estate properties	17,328	90,036	141,761	3,870,871
Net gain on sales of land parcels		4,037	19,170	15,759
Income from continuing operations	144,196	217,246	498,297	4,177,599
Discontinued operations, net	0	246	0	124
Net income	144,196	217,492	498,297	4,177,723
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Net income attributable to controlling interests	$ 138,229	$ 208,316	$ 478,012	$ 4,014,913
Earnings per Unit – basic:
Income from continuing operations available to Units	$ 0.37	$ 0.57	$ 1.30	$ 11
Net income available to Units	0.37	0.57	1.30	11
Earnings per Unit – diluted:
Income from continuing operations available to Units	0.37	0.56	1.29	10.92
Net income available to Units	$ 0.37	$ 0.56	$ 1.29	$ 10.92
Weighted average Units outstanding	382,945	382,373	382,640	382,284
ERPOP [Member]
REVENUES
Rental income	$ 623,951	$ 605,856	$ 1,840,170	$ 1,816,960
Fee and asset management	171	218	532	3,351
Total revenues	624,122	606,074	1,840,702	1,820,311
EXPENSES
Property and maintenance	104,721	104,216	306,645	309,688
Real estate taxes and insurance	84,087	81,343	253,318	238,954
Property management	20,861	19,517	64,702	64,003
General and administrative	12,567	12,395	40,366	47,408
Depreciation	184,100	179,230	542,964	528,242
Total expenses	406,336	396,701	1,207,995	1,188,295
Operating income	217,786	209,373	632,707	632,016
Interest and other income	3,945	5,509	5,708	65,092
Other expenses	(1,028)	(10,420)	(3,160)	(14,480)
Interest:
Expense incurred, net	(91,145)	(86,352)	(288,579)	(386,316)
Amortization of deferred financing costs	(2,064)	(2,261)	(6,447)	(10,000)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations	127,494	115,849	340,229	286,312
Income and other tax (expense) benefit	(228)	(426)	(710)	(1,189)
(Loss) income from investments in unconsolidated entities	(398)	7,750	(2,153)	5,846
Net gain on sales of real estate properties	17,328	90,036	141,761	3,870,871
Net gain on sales of land parcels		4,037	19,170	15,759
Income from continuing operations	144,196	217,246	498,297	4,177,599
Discontinued operations, net	0	246	0	124
Net income	144,196	217,492	498,297	4,177,723
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Net income attributable to controlling interests	143,395	216,669	495,943	4,175,355
ALLOCATION OF NET INCOME:
Preference Units	772	773	2,318	2,318
General Partner	137,457	207,543	475,694	4,012,595
Limited Partners	5,166	8,353	17,931	160,442
Net income available to Units	$ 142,623	$ 215,896	$ 493,625	$ 4,173,037
Earnings per Unit – basic:
Income from continuing operations available to Units	$ 0.37	$ 0.57	$ 1.30	$ 11
Net income available to Units	$ 0.37	$ 0.57	$ 1.30	$ 11
Weighted average Units outstanding	379,906	379,008	379,716	378,745
Earnings per Unit – diluted:
Income from continuing operations available to Units	$ 0.37	$ 0.56	$ 1.29	$ 10.92
Net income available to Units	$ 0.37	$ 0.56	$ 1.29	$ 10.92
Weighted average Units outstanding	382,945	382,373	382,640	382,284
Distributions declared per Unit outstanding	$ 0.50375	$ 3.50375	$ 1.51125	$ 12.51125

CONSOLIDATED STATEMENTS OF CO10

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Comprehensive income
Net income	$ 144,196	$ 217,492	$ 498,297	$ 4,177,723
Other comprehensive income (loss) – derivative instruments:
Unrealized holding gains (losses) arising during the period	1,709	227	5,216	(4,240)
Losses reclassified into earnings from other comprehensive income	4,768	4,340	14,019	37,262
Other comprehensive income (loss) – foreign currency:
Currency translation adjustments arising during the period		214		264
Other comprehensive income	6,477	4,781	19,235	33,286
Comprehensive income	150,673	222,273	517,532	4,211,009
Comprehensive (income) attributable to Noncontrolling Interests – Partially Owned Properties	(6,201)	(9,362)	(20,983)	(164,096)
Comprehensive income attributable to controlling interests	144,472	212,911	496,549	4,046,913
ERPOP [Member]
Comprehensive income
Net income	144,196	217,492	498,297	4,177,723
Other comprehensive income (loss) – derivative instruments:
Unrealized holding gains (losses) arising during the period	1,709	227	5,216	(4,240)
Losses reclassified into earnings from other comprehensive income	4,768	4,340	14,019	37,262
Other comprehensive income (loss) – foreign currency:
Currency translation adjustments arising during the period		214		264
Other comprehensive income	6,477	4,781	19,235	33,286
Comprehensive income	150,673	222,273	517,532	4,211,009
Comprehensive (income) attributable to Noncontrolling Interests – Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Comprehensive income attributable to controlling interests	$ 149,872	$ 221,450	$ 515,178	$ 4,208,641

CONSOLIDATED STATEMENTS OF CA11

CONSOLIDATED STATEMENTS OF CASH FLOWS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 498,297	$ 4,177,723
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	542,964	528,242
Amortization of deferred financing costs	6,447	10,000
Amortization of above/below market lease intangibles	2,729	2,566
Amortization of discounts and premiums on debt	4,939	(18,328)
Amortization of deferred settlements on derivative instruments	14,010	37,187
Write-off of pursuit costs	2,329	3,379
Loss (income) from investments in unconsolidated entities	2,153	(5,846)
Distributions from unconsolidated entities – return on capital	2,031	2,165
Net (gain) on sales of investment securities and other investments		(58,416)
Net (gain) on sales of real estate properties	(141,761)	(3,870,871)
Net (gain) on sales of land parcels	(19,170)	(15,759)
Net (gain) on sales of discontinued operations		(43)
Compensation paid with Company Common Shares	19,999	25,540
Changes in assets and liabilities:
Decrease in deposits – restricted	788	9,992
Decrease in mortgage deposits	1,447	222
(Increase) decrease in other assets	(23,024)	4,248
Increase in accounts payable and accrued expenses	62,635	41,371
Increase (decrease) in accrued interest payable	11,865	(15,780)
(Decrease) in other liabilities	(28,250)	(24,749)
Increase (decrease) in security deposits	2,606	(13,522)
Net cash provided by operating activities	963,034	819,321
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(466,395)	(205,881)
Investment in real estate – development/other	(227,187)	(454,502)
Capital expenditures to real estate	(143,258)	(124,551)
Non-real estate capital additions	(776)	(4,467)
Interest capitalized for real estate under development	(23,164)	(41,658)
Proceeds from disposition of real estate, net	350,000	6,584,126
Investments in unconsolidated entities	(5,324)	(3,826)
Distributions from unconsolidated entities – return of capital	329	13,798
Proceeds from sale of investment securities and other investments		72,815
Decrease (increase) in deposits on real estate acquisitions and investments, net	39,519	(83,668)
(Increase) in mortgage deposits	(4,541)	(21)
Net cash (used for) provided by investing activities	(480,797)	5,752,165
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(6,272)	(507)
Mortgage deposits	57,057	(6,249)
Mortgage notes payable, net:
Lump sum payoffs	(493,420)	(565,084)
Scheduled principal repayments	(8,771)	(6,644)
Notes, net:
Proceeds	692,466
Lump sum payoffs	(394,077)	(1,500,000)
Line of credit and commercial paper:
Line of credit proceeds	1,845,000	246,000
Line of credit repayments	(1,845,000)	(246,000)
Commercial paper proceeds	3,888,675	1,324,784
Commercial paper repayments	(3,681,750)	(1,712,472)
Proceeds from settlement of derivative instruments	1,296
Proceeds from EQR's Employee Share Purchase Plan (ESPP)	2,963	2,778
Proceeds from exercise of EQR options	12,967	26,939
Payment of offering costs	(36)	(304)
Other financing activities, net	(40)	(33)
Contributions – Noncontrolling Interests – Partially Owned Properties	125
Contributions – Limited Partners		1
Distributions:
OP Units – General Partner	(554,267)	(3,490,838)
Preference Units	(2,318)	(2,318)
OP Units – Limited Partners	(20,604)	(137,641)
Noncontrolling Interests – Partially Owned Properties	(6,873)	(28,588)
Net cash (used for) financing activities	(512,879)	(6,096,176)
Net (decrease) increase in cash and cash equivalents	(30,642)	475,310
Cash and cash equivalents, beginning of period	77,207	42,276
Cash and cash equivalents, end of period	46,565	517,586
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	257,805	383,374
Net cash paid for income and other taxes	964	1,333
Real estate acquisitions/dispositions/other:
Mortgage loans assumed		43,400
Amortization of deferred financing costs:
Other assets	1,810	2,291
Mortgage notes payable, net	1,943	3,320
Notes, net	2,694	4,389
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	247	(21,318)
Notes, net	1,771	2,578
Line of credit and commercial paper	2,921	412
Amortization of deferred settlements on derivative instruments:
Other liabilities	(9)	(75)
Accumulated other comprehensive income	14,019	37,262
Write-off of pursuit costs:
Investment in real estate, net	2,292	2,876
Other assets	17	399
Accounts payable and accrued expenses	20	104
Loss (income) from investments in unconsolidated entities:
Investments in unconsolidated entities	1,076	(6,999)
Other liabilities	1,077	1,153
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(3,803)	(4,563)
Notes, net	(1,413)	4,563
Other liabilities		4,240
Accumulated other comprehensive income	5,216	(4,240)
Investments in unconsolidated entities:
Investments in unconsolidated entities	(2,324)	(1,726)
Other liabilities	(3,000)	(2,100)
Distributions from unconsolidated entities - return of capital:
Investments in unconsolidated entities	329	14,014
Other assets		(216)
Debt financing costs:
Mortgage notes payable, net		(507)
Notes, net	(6,272)
Other:
Foreign currency translation adjustments		(264)
ERPOP [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	498,297	4,177,723
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	542,964	528,242
Amortization of deferred financing costs	6,447	10,000
Amortization of above/below market lease intangibles	2,729	2,566
Amortization of discounts and premiums on debt	4,939	(18,328)
Amortization of deferred settlements on derivative instruments	14,010	37,187
Write-off of pursuit costs	2,329	3,379
Loss (income) from investments in unconsolidated entities	2,153	(5,846)
Distributions from unconsolidated entities – return on capital	2,031	2,165
Net (gain) on sales of investment securities and other investments		(58,416)
Net (gain) on sales of real estate properties	(141,761)	(3,870,871)
Net (gain) on sales of land parcels	(19,170)	(15,759)
Net (gain) on sales of discontinued operations		(43)
Compensation paid with Company Common Shares	19,999	25,540
Changes in assets and liabilities:
Decrease in deposits – restricted	788	9,992
Decrease in mortgage deposits	1,447	222
(Increase) decrease in other assets	(23,024)	4,248
Increase in accounts payable and accrued expenses	62,635	41,371
Increase (decrease) in accrued interest payable	11,865	(15,780)
(Decrease) in other liabilities	(28,250)	(24,749)
Increase (decrease) in security deposits	2,606	(13,522)
Net cash provided by operating activities	963,034	819,321
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(466,395)	(205,881)
Investment in real estate – development/other	(227,187)	(454,502)
Capital expenditures to real estate	(143,258)	(124,551)
Non-real estate capital additions	(776)	(4,467)
Interest capitalized for real estate under development	(23,164)	(41,658)
Proceeds from disposition of real estate, net	350,000	6,584,126
Investments in unconsolidated entities	(5,324)	(3,826)
Distributions from unconsolidated entities – return of capital	329	13,798
Proceeds from sale of investment securities and other investments		72,815
Decrease (increase) in deposits on real estate acquisitions and investments, net	39,519	(83,668)
(Increase) in mortgage deposits	(4,541)	(21)
Net cash (used for) provided by investing activities	(480,797)	5,752,165
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(6,272)	(507)
Mortgage deposits	57,057	(6,249)
Mortgage notes payable, net:
Lump sum payoffs	(493,420)	(565,084)
Scheduled principal repayments	(8,771)	(6,644)
Notes, net:
Proceeds	692,466
Lump sum payoffs	(394,077)	(1,500,000)
Line of credit and commercial paper:
Line of credit proceeds	1,845,000	246,000
Line of credit repayments	(1,845,000)	(246,000)
Commercial paper proceeds	3,888,675	1,324,784
Commercial paper repayments	(3,681,750)	(1,712,472)
Proceeds from settlement of derivative instruments	1,296
Proceeds from EQR's Employee Share Purchase Plan (ESPP)	2,963	2,778
Proceeds from exercise of EQR options	12,967	26,939
Payment of offering costs	(36)	(304)
Other financing activities, net	(40)	(33)
Contributions – Noncontrolling Interests – Partially Owned Properties	125
Contributions – Limited Partners		1
Distributions:
OP Units – General Partner	(554,267)	(3,490,838)
Preference Units	(2,318)	(2,318)
OP Units – Limited Partners	(20,604)	(137,641)
Noncontrolling Interests – Partially Owned Properties	(6,873)	(28,588)
Net cash (used for) financing activities	(512,879)	(6,096,176)
Net (decrease) increase in cash and cash equivalents	(30,642)	475,310
Cash and cash equivalents, beginning of period	77,207	42,276
Cash and cash equivalents, end of period	46,565	517,586
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	257,805	383,374
Net cash paid for income and other taxes	964	1,333
Real estate acquisitions/dispositions/other:
Mortgage loans assumed		43,400
Amortization of deferred financing costs:
Other assets	1,810	2,291
Mortgage notes payable, net	1,943	3,320
Notes, net	2,694	4,389
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	247	(21,318)
Notes, net	1,771	2,578
Line of credit and commercial paper	2,921	412
Amortization of deferred settlements on derivative instruments:
Other liabilities	(9)	(75)
Accumulated other comprehensive income	14,019	37,262
Write-off of pursuit costs:
Investment in real estate, net	2,292	2,876
Other assets	17	399
Accounts payable and accrued expenses	20	104
Loss (income) from investments in unconsolidated entities:
Investments in unconsolidated entities	1,076	(6,999)
Other liabilities	1,077	1,153
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(3,803)	(4,563)
Notes, net	(1,413)	4,563
Other liabilities		4,240
Accumulated other comprehensive income	5,216	(4,240)
Investments in unconsolidated entities:
Investments in unconsolidated entities	(2,324)	(1,726)
Other liabilities	(3,000)	(2,100)
Distributions from unconsolidated entities - return of capital:
Investments in unconsolidated entities	329	14,014
Other assets		(216)
Debt financing costs:
Mortgage notes payable, net		(507)
Notes, net	$ (6,272)
Other:
Foreign currency translation adjustments		$ (264)

CONSOLIDATED STATEMENT OF CHA12

CONSOLIDATED STATEMENT OF CHANGES IN CAPITAL OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Total	ERPOP [Member]	PREFERRED SHARESERPOP [Member]	General Partner [Member]ERPOP [Member]	Limited Partner [Member]ERPOP [Member]	ACCUMULATED OTHER COMPREHENSIVE (LOSS) [Member]ERPOP [Member]	PARTIALLY OWNED PROPERTIES [Member]ERPOP [Member]
Balance, beginning of year at Dec. 31, 2016			$ 37,280	$ 10,305,707	$ 221,297	$ (113,909)
Balance, beginning of year at Dec. 31, 2016							$ 10,609
OP Unit Issuance:
Conversion of OP Units held by Limited Partners into OP Units held by General Partner				14,717	(14,717)
Exercise of EQR share options				12,967
EQR's Employee Share Purchase Plan (ESPP)				2,963
Share-based employee compensation expense:
EQR restricted shares				7,489
EQR share options				6,384
EQR ESPP discount				586
Net income available to Units – General Partner		$ 475,694		475,694
OP Units – General Partner distributions				(555,071)
Offering costs				(36)
Supplemental Executive Retirement Plan (SERP)				(594)
Change in market value of Redeemable Limited Partners				29,551
Adjustment for Limited Partners ownership in Operating Partnership				16,306	(16,306)
LIMITED PARTNERS
Conversion of OP Units held by Limited Partners into OP Units held by General Partner				14,717	(14,717)
Equity compensation associated with Units – Limited Partners					8,200
Net income available to Units – Limited Partners		17,931			17,931
Units – Limited Partners distributions					(20,073)
Change in carrying value of Redeemable Limited Partners					32,000
Adjustment for Limited Partners ownership in Operating Partnership				16,306	(16,306)
Accumulated other comprehensive income – derivative instruments:
Unrealized holding gains (losses) arising during the period	$ 5,216	5,216				5,216
Losses reclassified into earnings from other comprehensive income	(14,019)	(14,019)				14,019
NONCONTROLLING INTERESTS – PARTIALLY OWNED PROPERTIES
Net income attributable to Noncontrolling Interests	498,297	498,297					2,354
Contributions – Noncontrolling Interests – Partially Owned Properties	$ 125	$ 125					125
Distributions to Noncontrolling Interests							(6,913)
Balance, end of period at Sep. 30, 2017			$ 37,280	$ 10,316,663	$ 228,332	$ (94,674)
Balance, end of period at Sep. 30, 2017							$ 6,175

Business

Business	9 Months Ended
	Sep. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Business	1. Business Equity Residential (“EQR”), a Maryland real estate investment trust (“REIT”) formed in March 1993, is an S&P 500 company focused on the acquisition, development and management of rental apartment properties in urban and high-density suburban coastal gateway markets. ERP Operating Limited Partnership ("ERPOP"), an Illinois limited partnership, was formed in May 1993 to conduct the multifamily residential property business of Equity Residential. EQR has elected to be REIT. ERPOP. ERPOP. EQR is the general partner of, and as of September 30, 2017 owned an approximate 96.4% ownership interest in, ERPOP. All of the Company's property ownership, development and related business operations are conducted through the Operating Partnership ERPOP. ERPOP, As of September 30, 2017, the Company, directly or indirectly through investments in title holding entities, owned all or a portion of 305 properties located in 10 states and the District of Columbia consisting of 78,302 apartment units. The ownership breakdown includes (table does not include various uncompleted development properties): Properties Apartment Units Wholly Owned Properties 283 73,289 Master-Leased Properties – Consolidated 3 853 Partially Owned Properties – Consolidated 17 3,215 Partially Owned Properties – Unconsolidated 2 945 305 78,302

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2017
Summary Of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) and certain reclassifications considered necessary for a fair presentation have been included. Certain reclassifications have been made to the prior period financial statements in order to conform to the current year presentation. These reclassifications did not have an impact on net income previously reported. Operating results for the nine months ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017. In preparation of the Company’s financial statements in conformity with accounting principles generally accepted in the United States, management makes estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. The balance sheets at December 31, 2016 have been derived from the audited financial statements at that date but do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. For further information, including definitions of capitalized terms not defined herein, refer to the consolidated financial statements and footnotes thereto included in the Company’s and the Operating Partnership's Annual Report on Form 10-K for the year ended December 31, 2016. Income and Other Taxes Due to the structure of EQR as a REIT and the nature of the operations of its operating properties, no provision for federal income taxes has been made at the EQR level. In addition, ERPOP generally is not liable for federal income taxes as the partners recognize their proportionate share of income or loss in their tax returns; therefore no provision for federal income taxes has been made at the ERPOP level. Historically, the Company has generally only incurred certain state and local income, excise and franchise taxes. The Company has elected Taxable REIT Subsidiary (“TRS”) status for certain of its corporate subsidiaries and as a result, these entities will incur both federal and state income taxes on any taxable income of such entities after consideration of any net operating losses. 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 bases. These assets and liabilities are measured using enacted tax rates for which the temporary differences are expected to be recovered or settled. The effects of changes in tax rates on deferred tax assets and liabilities are recognized in earnings in the period enacted. The Company’s deferred tax assets were generally the result of tax affected suspended interest deductions, net operating losses, differing depreciable lives on capitalized assets and the timing of expense recognition for certain accrued liabilities. As of September 30, 2017, the Company has elected REIT status for its primary TRS upon filing the 2016 tax return in the third quarter of 2017, with the election retroactive to January 1, 2016. As a result, the Company wrote-off its deferred tax assets, which were fully reserved, as of September 30, 2017. Recently Issued Accounting Pronouncements In "FASB") Revenue from Contracts with Customers any, In FASB In • Lessors – Leases will be accounted for using an approach that is substantially equivalent to existing guidance for operating, sales-type and financing leases, but aligned with the new revenue recognition standard. Lessors will be required to allocate lease payments to separate lease and non-lease components of each lease agreement, with the non-lease components evaluated under the new revenue recognition standard. • Lessees – Leases will be accounted for using a dual approach, classifying leases as either operating or finance based on the principle of whether or not the lease is effectively a financed purchase of the leased asset by the lessee. This classification will determine whether the lease expense is recognized on a straight-line basis over the term of the lease (for operating leases) or based on an effective interest method with a front-loaded expense recognition (for finance leases). A lessee is also required to record a right-of-use asset and a lease liability on its balance sheet for all leases with a term of greater than 12 months regardless of their classification as operating or finance leases. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases. The new standard will be effective for the Company beginning on January 1, 2019, with early adoption permitted, though the Company currently anticipates adopting the new standard on the effective date. The new standard must be adopted using a modified retrospective method, which requires application of the new guidance at the beginning of the earliest comparative period presented and provides for certain practical expedients, which the Company currently anticipates electing. The Company anticipates that its residential and retail/commercial leases where it is the lessor will continue to be accounted for as operating leases under the new standard. Therefore, the Company does not currently anticipate significant changes in the accounting for its lease revenues. The Company is also the lessee under various corporate office and ground leases, which it will be required to recognize right of use assets and related lease liabilities on its consolidated balance sheets upon adoption. The Company currently anticipates that its corporate office leases where it is the lessee will continue to be accounted for as operating leases under the new standard. Based on its anticipated election of the practical expedients, the Company would not be required to reassess the classification of existing ground leases and therefore these leases would continue to be accounted for as operating leases. However, in the event we modify existing ground leases and/or enter into new ground leases after adoption of the new standard, such leases will likely be classified as finance leases. The Company will continue to evaluate the impact of adopting the new leases standard on its consolidated results of operations and financial position. In June 2016, the FASB In FASB • Cash payments related to debt prepayments or extinguishment costs are to be classified within financing • The portion of the cash payment made to settle a zero-coupon bond or a bond with an insignificant cash coupon attributable to accreted interest related to a debt discount is to be classified as a cash outflow within operating activities, and the portion attributable to the principal is to be classified within financing • Insurance settlement proceeds are to be classified based on the nature of the • Companies must elect to classify distributions received from equity method investees using either a cumulative earnings approach or a look-through approach and the election must be disclosed; • Restricted Total The The Company does not expect overall cash flows to change; however, there will be material changes between cash flow classifications due to the substantial debt prepayment penalties that the Company has incurred in the comparative period. In FASB clarifies the accounting treatment for partial sales of nonfinancial assets (i.e. real estate). The standard clarifies that partial sales transactions include contributions of nonfinancial assets to a joint venture or other noncontrolled investee. Companies must recognize a full gain or loss on transfers of nonfinancial assets to equity method investees. The standard requires companies to derecognize distinct nonfinancial assets or distinct in substance nonfinancial assets in partial sale transactions when it does not have a controlling financial interest in the legal entity that holds the asset and transfers control of the asset. Once the distinct nonfinancial asset is transferred, the company is required to measure any non-controlling interest it receives or retains at fair value and recognize a full gain or loss on the transaction. If a company transfers ownership interests in a consolidated subsidiary and continues to maintain a controlling financial interest, the company does not derecognize the assets or liabilities, and accounts for the transaction as an equity transaction and no gain or loss is recognized. The new standard will be effective for the Company beginning on January 1, 2018 and early adoption was permitted beginning on January 1, 2017. The Company anticipates adopting the new standard concurrently with the new revenue recognition standard. The new standard may be applied retrospectively to each prior period presented or prospectively with the cumulative effect recognized as of the date of adoption. The Company has not had a partial sale of nonfinancial assets in the current or comparative periods. Therefore, the Company does not currently believe that the adoption of this standard will have a material impact on its consolidated results of operations and financial position. In August 2017, the FASB issued a final standard which makes changes to the hedge accounting model to enable entities to better portray their risk management activities in the financial statements. The new standard expands an entity’s ability to hedge nonfinancial and financial risk components, reduces complexity in fair value hedges of interest rate risk and eases certain documentation and assessment requirements. The new standard also eliminates the requirement to separately measure and report hedge ineffectiveness and generally requires the entire change in the fair value of any hedging instrument to be presented in the same income statement line as the hedged instrument. The new standard will be effective for the Company beginning on January 1, 2019 and early adoption is permitted. The Company is currently evaluating the impact of adopting the new standard on its consolidated results of operations and financial position. Recently Adopted Accounting Pronouncements In FASB Generally, In FASB In FASB Other The Company is the controlling partner in various consolidated partnerships owning 17 properties and 3,215 apartment units having a noncontrolling interest book value of $6.2 million at September 30, 2017. The Company is required to make certain disclosures regarding noncontrolling interests in consolidated limited-life subsidiaries. Of the consolidated entities described above, the Company is the controlling partner in limited-life partnerships owning four properties having a noncontrolling interest deficit balance of $7.3 million. These four partnership agreements contain provisions that require the partnerships to be liquidated through the sale of their assets upon reaching a date specified in each respective partnership agreement. The Company, as controlling partner, has an obligation to cause the property owning partnerships to distribute the proceeds of liquidation to the Noncontrolling Interests in these Partially Owned Properties only to the extent that the net proceeds received by the partnerships from the sale of their assets warrant a distribution based on the partnership agreements. As of September 30, 2017, the Company estimates the value of Noncontrolling Interest distributions for these four properties would have been approximately $65.8 million (“Settlement Value”) had the partnerships been liquidated. This Settlement Value is based on estimated third party consideration realized by the partnerships upon disposition of the four Partially Owned Properties and is net of all other assets and liabilities, including yield maintenance on the mortgages encumbering the properties, that would have been due on had those mortgages been prepaid. Due to, among other things, the inherent uncertainty in the sale of real estate assets, the amount of any potential distribution to the Noncontrolling Interests in the Company's Partially Owned Properties is subject to change. To the extent that the partnerships' underlying assets are worth less than the underlying liabilities, the Company has no obligation to remit any consideration to the Noncontrolling Interests in these Partially Owned Properties

Equity, Capital and Other Inter

Equity, Capital and Other Interests	9 Months Ended
	Sep. 30, 2017
Equity Capital And Other Interests [Abstract]
Equity, Capital and Other Interests	3. Equity, Capital and Other Equity and Redeemable Noncontrolling Interests of Equity Residential The following tables present the changes in the Company’s issued and outstanding Common Shares and “Units” (which includes OP Units and restricted units) for the nine months ended September 30, 2017: 2017 Common Shares Common Shares outstanding at January 1, 365,870,924 Common Shares Issued: Conversion of OP Units 1,107,735 Exercise of share options 343,527 Employee Share Purchase Plan (ESPP) 54,843 Restricted share grants, net 85,451 Common Shares Outstanding at September 30, 367,462,480 Units Units outstanding at January 1, 14,626,075 Restricted unit grants, net 291,647 Conversion of OP Units to Common Shares (1,107,735 ) Units outstanding at September 30, 13,809,987 Total Common Shares and Units outstanding at September 30, 381,272,467 Units Ownership Interest in Operating Partnership 3.6 % The equity positions of various individuals and entities that contributed their properties to the Operating Partnership in exchange for OP Units, as well as the equity positions of the holders of restricted units, are collectively referred to as the “Noncontrolling Interests – Operating Partnership”. Subject to certain exceptions (including the “book-up” requirements of restricted units), the Noncontrolling Interests – Operating Partnership may exchange their Units with EQR for Common Shares on a one-for-one basis. The carrying value of the Noncontrolling Interests – Operating Partnership (including redeemable interests) is allocated based on the number of Noncontrolling Interests – Operating Partnership Units in total in proportion to the number of Noncontrolling Interests – Operating Partnership Units in total plus the number of Common Shares. Net income is allocated to the Noncontrolling Interests – Operating Partnership based on the weighted average ownership percentage during the period. The Operating Partnership has the right but not the obligation to make a cash payment instead of issuing Common Shares to any and all holders of Noncontrolling Interests – Operating Partnership Units requesting an exchange of their OP Units with EQR. Once the Operating Partnership elects not to redeem the Noncontrolling Interests – Operating Partnership Units for cash, EQR is obligated to deliver Common Shares to the exchanging holder of the Noncontrolling Interests – Operating Partnership Units. The law, Instruments that require settlement in registered shares cannot be classified in permanent equity as it is not always completely within an issuer’s control to deliver registered shares. Therefore, settlement in cash is assumed and that responsibility for settlement in cash is deemed to fall to the Operating Partnership as the primary source of cash for EQR, resulting in presentation in the mezzanine section of the balance sheet. The Redeemable Noncontrolling Interests – Operating Partnership are adjusted to the greater of carrying value or fair market value based on the Common Share price of EQR at the end of each respective reporting period. EQR has the ability to deliver unregistered Common Shares for the remaining portion of the Noncontrolling Interests – Operating Partnership Units that are classified in permanent equity at September 30, 2017 and December 31, 2016. The The 2017 Balance at January 1, $ 442,092 Change in market value (29,551 ) Change in carrying value (32,000 ) Balance at September 30, $ 380,541 Net proceeds from EQR Common Share and Preferred Share (see definition below) offerings are contributed by EQR to ERPOP. In return for those contributions, EQR receives a number of OP Units in ERPOP equal to the number of Common Shares it has issued in the equity offering (or in the case of a preferred equity offering, a number of preference units in ERPOP equal in number and having the same terms as the Preferred Shares issued in the equity offering). As a result, the net offering proceeds from Common Shares and Preferred Shares are allocated between shareholders’ equity and Noncontrolling Interests – Operating Partnership to account for the change in their respective percentage ownership of the underlying equity of ERPOP. The The Amounts in thousands Annual Call Dividend per September 30, December 31, Date (1) Share (2) 2017 2016 Preferred Shares of beneficial interest, $0.01 par value; 100,000,000 shares authorized: 8.29% Series K Cumulative Redeemable Preferred; liquidation value $50 per share; 745,600 shares issued and outstanding at September 30, 2017 and December 31, 2016 12/10/26 $ 4.145 $ 37,280 $ 37,280 $ 37,280 $ 37,280 (1) On or after the call date, redeemable preferred shares may be redeemed for cash at the option of the Company, in whole or in part, at a redemption price equal to the liquidation price per share, plus accrued and unpaid distributions, if any. (2) Dividends on Preferred Shares are payable quarterly. Capital and Redeemable Limited Partners of ERP Operating Limited Partnership The following tables present the changes in the Operating Partnership’s issued and outstanding Units and in the limited partners’ Units for the nine months ended September 30, 2017: 2017 General and Limited Partner Units General and Limited Partner Units outstanding at January 1, 380,496,999 Issued to General Partner: Exercise of EQR share options 343,527 EQR’s Employee Share Purchase Plan (ESPP) 54,843 EQR's restricted share grants, net 85,451 Issued to Limited Partners: Restricted unit grants, net 291,647 General and Limited Partner Units outstanding at September 30, 381,272,467 Limited Partner Units Limited Partner Units outstanding at January 1, 14,626,075 Limited Partner restricted unit grants, net 291,647 Conversion of Limited Partner OP Units to EQR Common Shares (1,107,735 ) Limited Partner Units outstanding at September 30, 13,809,987 Limited Partner Units Ownership Interest in Operating Partnership 3.6 % The Limited Partners of the Operating Partnership as of September 30, 2017 include various individuals and entities that contributed their properties to the Operating Partnership in exchange for OP Units, as well as the equity positions of the holders of restricted units. Subject to certain exceptions (including the “book-up” requirements of restricted units), Limited Partners may exchange their Units with EQR for Common Shares on a one-for-one basis. The carrying value of the Limited Partner Units (including redeemable interests) is allocated based on the number of Limited Partner Units in total in proportion to the number of Limited Partner Units in total plus the number of General Partner Units. Net income is allocated to the Limited Partner Units based on the weighted average ownership percentage during the period. The Operating Partnership has the right but not the obligation to make a cash payment instead of issuing Common Shares to any and all holders of Limited Partner Units requesting an exchange of their OP Units with EQR. Once the Operating Partnership elects not to redeem the Limited Partner Units for cash, EQR is obligated to deliver Common Shares to the exchanging limited partner. The Limited Partner Units are classified as either mezzanine equity or permanent equity. If EQR is required, either by contract or securities law, to deliver registered Common Shares, such Limited Partner Units are differentiated and referred to as “Redeemable Limited Partner Units”. Instruments that require settlement in registered shares cannot be classified in permanent equity as it is not always completely within an issuer's control to deliver registered shares. Therefore, settlement in cash is assumed and that responsibility for settlement in cash is deemed to fall to the Operating Partnership as the primary source of cash for EQR, resulting in presentation in the mezzanine section of the balance sheet. The Redeemable Limited Partner Units are adjusted to the greater of carrying value or fair market value based on the Common Share price of EQR at the end of each respective reporting period. EQR has the ability to deliver unregistered Common Shares for the remaining portion of the Limited Partner Units that are classified in permanent equity at September 30, 2017 and . The carrying value of the Redeemable Limited Partner Units is allocated based on the number of Redeemable Limited Partner The following table presents the changes in the redemption value of the Redeemable Limited Partners for the nine months ended September 30, 2017 (amounts in thousands): 2017 Balance at January 1, $ 442,092 Change in market value (29,551 ) Change in carrying value (32,000 ) Balance at September 30, $ 380,541 EQR contributes all net proceeds from its various equity offerings (including proceeds from exercise of options for Common ERPOP. The December 31, 2016 Amounts in thousands Annual Call Dividend Per September 30, December 31, Date (1) Unit (2) 2017 2016 Preference Units: 8.29% Series K Cumulative Redeemable Preference Units; liquidation value $50 per unit; 745,600 units issued and outstanding at September 30, 2017 and December 31, 2016 12/10/26 $ 4.145 $ 37,280 $ 37,280 $ 37,280 $ 37,280 (1) On or after the call date, redeemable preference units may be redeemed for cash at the option of the Operating Partnership, in whole or in part, at a redemption price equal to the liquidation price per unit, plus accrued and unpaid distributions, if any, in conjunction with the concurrent redemption of the corresponding Company Preferred Shares. (2) Dividends on Preference Units are payable quarterly. Other In September 2009, the Company announced the establishment of an At-The-Market (“ATM”) The Company may repurchase up to 13.0 million Common Shares under its share repurchase program. No shares were repurchased during the nine months ended September 30, 2017 and as a result, EQR has remaining authorization to repurchase up to 13.0 million of its shares under the repurchase program as of September 30, 2017.

Real Estate and Lease Intangibl

Real Estate and Lease Intangibles	9 Months Ended
	Sep. 30, 2017
Real Estate [Abstract]
Real Estate and Lease Intangibles	4. Real Estate and Lease Intangibles The following table summarizes the carrying amounts for the Company’s investment in real estate (at cost) as of September 30, 2017 and December 31, 2016 (amounts in thousands): September 30, 2017 December 31, 2016 Land $ 5,985,004 $ 5,899,862 Depreciable property: Buildings and improvements 17,601,348 16,913,430 Furniture, fixtures and equipment 1,500,963 1,346,300 In-Place lease intangibles 469,091 470,849 Projects under development: Land 61,047 115,876 Construction-in-progress 232,017 521,292 Land held for development: Land 63,439 84,440 Construction-in-progress 35,634 34,376 Investment in real estate 25,948,543 25,386,425 Accumulated depreciation (5,849,110 ) (5,360,389 ) Investment in real estate, net $ 20,099,433 $ 20,026,036 The following table summarizes the carrying amounts for the Company's above and below market ground and retail lease intangibles as of September 30, 2017 and December 31, 2016 (amounts in thousands): Description Balance Sheet Location September 30, 2017 December 31, 2016 Assets Ground lease intangibles – below market Other Assets $ 191,918 $ 178,251 Retail lease intangibles – above market Other Assets 1,260 1,260 Lease intangible assets 193,178 179,511 Accumulated amortization (21,305 ) (17,972 ) Lease intangible assets, net $ 171,873 $ 161,539 Liabilities Ground lease intangibles – above market Other Liabilities $ 2,400 $ 2,400 Retail lease intangibles – below market Other Liabilities 5,270 5,270 Lease intangible liabilities 7,670 7,670 Accumulated amortization (5,113 ) (4,509 ) Lease intangible liabilities, net $ 2,557 $ 3,161 The following table provides a summary of the effect of the amortization for above and below market ground and retail lease intangibles on Nine Months Ended Quarter Ended September 30, September 30, Description Income Statement Location 2017 2016 2017 2016 Ground lease intangible amortization Property and Maintenance $ (3,253 ) $ (3,241 ) $ (1,092 ) $ (1,080 ) Retail lease intangible amortization Rental Income 524 675 80 222 Total amortization of above/below market lease intangibles $ (2,729 ) $ (2,566 ) $ (1,012 ) $ (858 ) The following table provides a summary of the aggregate amortization for above and below market ground and retail lease intangibles for each of the next five years (amounts in thousands): Remaining 2017 2018 2019 2020 2021 2022 Ground lease intangibles $ (1,116 ) $ (4,463 ) $ (4,463 ) $ (4,463 ) $ (4,463 ) $ (4,463 ) Retail lease intangibles 16 71 71 71 71 27 Total $ (1,100 ) $ (4,392 ) $ (4,392 ) $ (4,392 ) $ (4,392 ) $ (4,436 ) During the nine months ended September 30, 2017, the Company acquired the entire equity interest in the following from unaffiliated parties (purchase price in thousands): Properties Apartment Units Purchase Price Rental Properties – Consolidated (1) 4 947 $ 468,050 Total 4 947 $ 468,050 (1) Purchase price includes an allocation of approximately $68.3 million to land, $386.2 million to depreciable property (inclusive of capitalized closing costs) and $13.7 million to ground lease intangible (included in other assets). For one of the property acquisitions, the Company owns the building and improvements and leases the land underlying the improvements under a long-term ground lease that expires in 2113. This property is consolidated and reflected as a real estate asset while the ground lease is accounted for as an operating lease. During the nine months ended September 30, 2017 , the Company disposed of the following to unaffiliated parties (sales price in thousands): Properties Apartment Units Sales Price Rental Properties – Consolidated 4 1,024 $ 319,700 Land Parcels (one) — — 33,450 Total 4 1,024 $ 353,150 The Company recognized a net gain on sales of real estate properties of approximately $141.8 million and a net gain on sales of land parcels of approximately $19.2 million on the above sales.

Commitments to Acquire_Dispose

Commitments to Acquire/Dispose of Real Estate	9 Months Ended
	Sep. 30, 2017
Commitments To Acquire Dispose Of Real Estate [Abstract]
Commitments to Acquire/Dispose of Real Estate	5. Commitments to Acquire/Dispose of Real The Company has not entered into any separate agreements to acquire rental properties or land parcels as of October 27, 2017. The Company has entered into a separate agreement to dispose of the following (sales price in thousands): Properties Apartment Units Sales Price Land Parcels (one) — — $ 2,700 Total — — $ 2,700 The closing of this pending transaction is subject to certain conditions and restrictions, therefore, there can be no assurance that this transaction will be consummated or that the final terms will not differ in material respects from those summarized above.

Investments in Partially Owned

Investments in Partially Owned Entities	9 Months Ended
	Sep. 30, 2017
Investments In Partially Owned Entities [Abstract]
Investments in Partially Owned Entities	6. Investments in Partially Owned The September 30, 2017 Consolidated Unconsolidated (VIE) (Non-VIE) (VIE) (1) Total Total properties 17 2 — 2 Total apartment units 3,215 945 — 945 Balance sheet information at 9/30/2017 (at 100%): ASSETS Investment in real estate $ 648,839 $ 236,630 $ 172,995 $ 409,625 Accumulated depreciation (226,607 ) (40,840 ) (48,670 ) (89,510 ) Investment in real estate, net 422,232 195,790 124,325 320,115 Cash and cash equivalents 22,914 7,194 139 7,333 Investments in unconsolidated entities 45,035 — — — Deposits – restricted 385 258 — 258 Other assets 26,246 450 105 555 Total assets $ 516,812 $ 203,692 $ 124,569 $ 328,261 LIABILITIES AND EQUITY/CAPITAL Mortgage notes payable, net (2) $ 302,037 $ 145,424 $ — $ 145,424 Accounts payable & accrued expenses 2,975 2,644 150 2,794 Accrued interest payable 1,024 691 — 691 Other liabilities 453 308 27 335 Security deposits 2,037 488 — 488 Total liabilities 308,526 149,555 177 149,732 Noncontrolling Interests – Partially Owned Properties/Partners' equity 6,175 54,336 84,682 139,018 Company equity/General and Limited Partners' Capital 202,111 (199 ) 39,710 39,511 Total equity/capital 208,286 54,137 124,392 178,529 Total liabilities and equity/capital $ 516,812 $ 203,692 $ 124,569 $ 328,261 Consolidated Unconsolidated (VIE) (Non-VIE) (VIE) (1) Total Operating information for the nine months ended 9/30/2017 (at 100%): Operating revenue $ 69,917 $ 20,050 $ 3,805 $ 23,855 Operating expenses 17,056 6,746 1,573 8,319 Net operating income 52,861 13,304 2,232 15,536 Property management 2,463 584 56 640 General and administrative/other 239 1 127 128 Depreciation 15,569 7,960 4,126 12,086 Operating income (loss) 34,590 4,759 (2,077 ) 2,682 Interest and other income 45 — — — Interest: Expense incurred, net (9,977 ) (6,217 ) — (6,217 ) Amortization of deferred financing costs (203 ) (1 ) — (1 ) Income (loss) before income and other taxes and (loss) from investments in unconsolidated entities 24,455 (1,459 ) (2,077 ) (3,536 ) Income and other tax (expense) benefit (34 ) (13 ) — (13 ) (Loss) from investments in unconsolidated entities (1,155 ) — — — Net income (loss) $ 23,266 $ (1,472 ) $ (2,077 ) $ (3,549 ) (1) Includes the Company’s unconsolidated interest in an entity that owns the land underlying our Wisconsin Place apartment property and owns and operates the parking facility. This entity is excluded from the property and apartment unit count. (2) All debt is non-recourse to the Company. Note: The above tables exclude EQR's ownership interest in ERPOP, private equity fund investments, and the Company's interests in unconsolidated joint ventures established in connection with the acquisition of certain real estate related assets from Archstone Enterprise LP ("Archstone"). Operating Properties The Company has various equity interests in certain limited partnerships owning 16 properties containing 2,783 apartment units. Each partnership owns a multifamily property. The Company is the general partner of these limited partnerships and is responsible for managing the operations and affairs of the partnerships as well as making all decisions regarding the businesses of the partnerships. The limited partners are not able to exercise substantive kick-out or participating rights. As a result, the partnerships qualify as VIEs. The Company has a controlling financial interest in the VIEs and, thus, is the VIEs' primary beneficiary. The Company has both the power to direct the activities of the VIEs that most significantly impact the VIEs' economic performance as well as the obligation to absorb losses or the right to receive benefits from the VIEs that could potentially be significant to the VIEs. As a result, the partnerships are required to be consolidated on the Company's financial statements. The Company has a 75% equity interest in the Wisconsin Place joint venture. The project contains a mixed-use site located in Chevy Chase, Maryland consisting of residential, retail, office and accessory uses, including underground parking facilities. The joint venture owns the 432 unit residential component, but has no ownership interest in the retail and office components. At September 30, 2017, the residential component had a net book value of $167.0 million. The Company is the managing member and is responsible for conducting all administrative day-to-day matters and affairs of the joint venture as well as implementing all decisions with respect to the joint venture. The limited partner is not able to exercise substantive kick-out or participating rights. As a result, the joint venture qualifies as a VIE. The Company has a controlling financial interest in the VIE and, thus, is the VIE's primary beneficiary. The Company has both the power to direct the activities of the VIE that most significantly impact the VIE's economic performance as well as the obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE. As a result, the entity that owns the residential component is required to be consolidated on the Company's financial statements. The Wisconsin Place joint venture also retains an unconsolidated interest in an entity that owns the land underlying the entire project and owns and operates the parking facility. At September 30, 2017, the basis of this investment was $45.0 million. The joint venture, as a limited partner, does not have substantive kick-out or participating rights in the entity. As a result, the entity qualifies as a VIE. The joint venture does not have a controlling financial interest in the VIE and is not the VIE's primary beneficiary. The joint venture does not have the power to direct the activities of the VIE that most significantly impact the VIE's economic performance or the obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE. As a result, the entity that owns the land and owns and operates the parking facility is unconsolidated and recorded using the equity method of accounting. The Company has a 20% equity interest in each of the Nexus Sawgrass and Domain joint ventures. The Nexus Sawgrass joint venture owns a 501 unit apartment property located in Sunrise, Florida and the Company's interest had a basis of $4.4 million at September 30, 2017. The Domain joint venture owns a 444 unit apartment property located in San Jose, California and the Company's interest had a basis of $8.4 million at September 30, 2017. Both properties were funded with long-term, non-recourse secured loans from the partner. The mortgage loan on Nexus Sawgrass has a current unconsolidated outstanding balance of $48.6 million, bears interest at 5.60% and matures January 1, 2021. The mortgage loan on Domain has a current unconsolidated outstanding balance of $96.8 million, bears interest at 5.75% and matures January 1, 2022. While the Company is the managing member of both of the joint ventures, the joint venture partner has significant participating rights and has active involvement in and oversight of the operations. As a result, the entities do not qualify as VIEs. The Company alone does not have the power to direct the activities of the entities that most significantly impact the entities' economic performance and as a result, the entities are unconsolidated and recorded using the equity method of accounting. Other As the sole general partner of ERPOP, EQR has exclusive control of ERPOP's day-to-day management. The limited partners are not able to exercise substantive kick-out or participating rights. As a result, ERPOP qualifies as a VIE. EQR has a controlling financial interest in ERPOP and, thus, is ERPOP's primary beneficiary. EQR has the power to direct the activities of ERPOP that most significantly impact ERPOP's economic performance as well as the obligation to absorb losses or the right to receive benefits from ERPOP that could potentially be significant to ERPOP. As a result, ERPOP is required to be consolidated on EQR's financial statements. The Company agreed to a maximum investment of $5.0 million each for two private equity funds, both of which primarily focus on real estate technology investments. The Company accounts for both investments under the equity method of accounting. As of September 30, 2017, the Company’s interest in these investments had a combined basis of $1.6 million. On February 27, 2013, in connection with the acquisition of Archstone, subsidiaries of the Company entered into three limited liability company agreements (collectively, the “Residual JV”). The Residual JV owned certain Archstone assets and succeeded to certain residual Archstone liabilities/litigation. The Residual JV is owned 60% by the Company and 40% by its joint venture partner. The On February 27, 2013, in connection with the acquisition of Archstone, a subsidiary of the Company entered into a limited liability company agreement (the “Legacy JV”), through which they assumed obligations of Archstone in the form of preferred interests, some of which are governed by tax protection arrangements. At September 30, 2017, the remaining preferred interests had an aggregate liquidation value of $37.4 million, our share of which is included in other liabilities in the accompanying consolidated balance sheets. Obligations of the Legacy JV are borne 60% by the Company and 40% by its joint venture partner. The Legacy JV is managed by a Management Committee consisting of two members from each of the Company and its joint venture partner. Both partners have equal participation in the Management Committee and all significant participating rights are shared by both partners. As a result, the Legacy JV does not qualify as a VIE. The Company alone does not have the power to direct the activities of the Legacy JV that most significantly impact the Legacy JV's economic performance and as a result, the Legacy JV is unconsolidated and recorded using the equity method of accounting.

Deposits - Restricted and Escro

Deposits - Restricted and Escrow Deposits - Mortgage	9 Months Ended
	Sep. 30, 2017
Deposits Restricted [Abstract]
Deposits - Restricted and Escrow Deposits - Mortgage	7. Deposits – Restricted and Escrow Deposits – Mortgage The following table presents the Company’s restricted deposits as of September 30, 2017 and December 31, 2016 (amounts in thousands): September 30, 2017 December 31, 2016 Tax-deferred (1031) exchange proceeds $ — $ 38,847 Restricted deposits on real estate investments 61 733 Resident security and utility deposits 35,667 37,007 Other 911 359 Totals $ 36,639 $ 76,946 The following table presents the Company’s escrow deposits for mortgages as of September 30, 2017 and December 31, 2016 (amounts in thousands): September 30, 2017 December 31, 2016 Real estate taxes and insurance $ 556 $ 2,003 Replacement reserves 7,969 3,428 Mortgage principal reserves/sinking funds 1,595 58,652 Other 852 852 Totals $ 10,972 $ 64,935 During the nine months ended September 30, 2017, the Company received approximately $60.5 million from the return of various mortgage principal reserves/sinking funds on certain tax-exempt mortgage bond deals.

Debt

Debt	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Debt	8. Debt EQR Mortgage Notes Payable As of September 30, 2017, the Company had outstanding mortgage debt of approximately $3.6 billion. During the nine months ended September 30, 2017, the Company: • Repaid $300.0 million of 5.987% mortgage debt held in a Fannie Mae loan pool maturing in 2019 and incurred a prepayment penalty of approximately $10.8 million; • Repaid $193.4 million of conventional fixed-rate mortgage loans maturing in 2017 through 2048 and incurred a prepayment penalty of approximately $1.5 million; and • Repaid $8.8 million of scheduled principal repayments on various mortgage debt. The Company recorded $0.3 million of write-offs of unamortized deferred financing costs during the nine months ended September 30, 2017 as additional interest expense related to debt extinguishment of mortgages. The Company also recorded $0.7 million of write-offs of net unamortized premiums during the nine months ended September 30, 2017 as a reduction of interest expense related to debt extinguishment of mortgages. As of September 30, 2017, the Company had $598.7 million of secured debt subject to third party credit enhancement. As September 30, 2017 Notes As of September 30, 2017, the Company had outstanding unsecured notes of approximately $5.1 billion. During the nine months ended September 30, 2017, the Company: • Repaid $394.1 million of 5.75% unsecured notes at maturity; • Issued $400.0 million of ten-year 3.25% fixed rate public notes, receiving net proceeds of approximately $399.3 million before underwriting fees, hedge termination costs and other expenses, at an all-in effective interest rate of 3.32% after termination of four forward starting swaps in conjunction with the issuance (see Note 9 for further discussion); and • Issued $300.0 million of thirty-year 4.00% fixed rate public notes, receiving net proceeds of approximately $293.2 million before underwriting fees and other expenses, at an all-in effective interest rate of 4.11%. As September 30, 2017 Line of Credit and Commercial Paper On November 3, 2016, the Company replaced its existing $2.5 billion facility with a $2.0 billion unsecured revolving credit facility maturing January 10, 2022. The Company has the ability to increase available borrowings by an additional $750.0 million by adding additional banks to the facility or obtaining the agreement of existing banks to increase their commitments. The interest rate on advances under the facility will generally be LIBOR plus a spread (currently 0.825%), or based on bids received from the lending group, and the Company pays an annual facility fee (currently 12.5 basis points). Both the spread and the facility fee are dependent on the credit rating of the Company’s long term debt. On September 30, 2017 As September 30, 2017 Other On April 24, 2017, the Company executed a new letter of credit facility with a third party financial institution which is not backed by or collateralized by borrowings on the Company’s unsecured revolving credit facility. As of September 30, 2017

Derivative and Other Fair Value

Derivative and Other Fair Value Instruments	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Derivative and Other Fair Value Instruments	9. Derivative and Other Fair Value The valuation of financial instruments requires the Company to make estimates and judgments that affect the fair value of the instruments. The Company, where possible, bases the fair values of its financial instruments, including its derivative instruments, on listed market prices and third party quotes. Where these are not available, the Company bases its estimates on current instruments with similar terms and maturities or on other factors relevant to the financial instruments. In the normal course of business, the Company is exposed to the effect of interest rate changes. The Company seeks to manage these risks by following established risk management policies and procedures including the use of derivatives to hedge interest rate risk on debt instruments. The Company may also use derivatives to manage commodity prices in the daily operations of the business. A • Level 1 – Inputs to the valuation methodology are quoted prices (unadjusted) for identical assets or liabilities in active markets. • Level 2 – Inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument. • Level 3 – Inputs to the valuation methodology are unobservable and significant to the fair value The Company’s derivative positions are valued using models developed by the respective counterparty as well as models developed internally by the Company that use as their basis readily observable market parameters (such as forward yield curves and credit default swap data). Employee holdings other than Common Shares within the supplemental executive retirement plan (the “SERP”) are valued using quoted market prices for identical assets and are included in other assets and other liabilities on the consolidated balance sheets. Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners are valued using the quoted market price of Common Shares. The fair values disclosed for mortgage notes payable and unsecured debt (including its commercial paper) were calculated using indicative rates provided by lenders of similar loans in the case of mortgage notes payable and the private unsecured debt (including its commercial paper) and quoted market prices for each underlying issuance in the case of the public unsecured notes. The fair values of the Company’s financial instruments (other than mortgage notes payable, unsecured notes, commercial paper, line of credit and derivative instruments), including cash and cash equivalents and other financial instruments, approximate their carrying or contract value. The September 30, 2017 December 31, 2016 Estimated Fair Value (Level 2) Carrying Value Estimated Fair Value (Level 2) Carrying Value Mortgage notes payable, net $ 3,630,477 $ 3,619,180 $ 4,161,001 $ 4,119,181 Unsecured debt, net 5,640,095 5,373,092 5,030,330 4,868,077 Total debt, net $ 9,270,572 $ 8,992,272 $ 9,191,331 $ 8,987,258 The September 30, 2017 Fair Value Hedges (1) Forward Starting Swaps (2) Current Notional Balance $ 450,000 $ 250,000 Lowest Interest Rate 2.375 % 2.1478 % Highest Interest Rate 2.375 % 2.2895 % Earliest Maturity Date 2019 2028 Latest Maturity Date 2019 2029 (1) Fair Value Hedges – Converts outstanding fixed rate unsecured notes ($450.0 million 2.375% notes due July 1, 2019) to a floating interest rate of 90-Day LIBOR plus 0.61%. (2) Forward Starting Swaps – Designed to partially fix interest rates in advance of planned future debt issuances. Of the $250.0 million notional balance, $200.0 million of these swaps have mandatory counterparty terminations in 2019 and are targeted for 2018 debt issuances while $50.0 million of these swaps have mandatory counterparty terminations in 2020 and are targeted for 2019 debt issuances. The Fair Value Measurements at Reporting Date Using Description Balance Sheet Location 9/30/2017 Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Derivatives designated as hedging instruments: Interest Rate Contracts: Fair Value Hedges Other Assets $ 444 $ — $ 444 $ — Forward Starting Swaps Other Assets 3,921 — 3,921 — Supplemental Executive Retirement Plan Other Assets 136,774 136,774 — — Total $ 141,139 $ 136,774 $ 4,365 $ — Liabilities Supplemental Executive Retirement Plan Other Liabilities $ 136,774 $ 136,774 $ — $ — Total $ 136,774 $ 136,774 $ — $ — Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners Mezzanine $ 380,541 $ — $ 380,541 $ — Fair Value Measurements at Reporting Date Using Description Balance Sheet Location 12/31/2016 Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Derivatives designated as hedging instruments: Interest Rate Contracts: Fair Value Hedges Other Assets $ 1,857 $ — $ 1,857 $ — Supplemental Executive Retirement Plan Other Assets 124,420 124,420 — — Total $ 126,277 $ 124,420 $ 1,857 $ — Liabilities Supplemental Executive Retirement Plan Other Liabilities $ 124,420 $ 124,420 $ — $ — Total $ 124,420 $ 124,420 $ — $ — Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners Mezzanine $ 442,092 $ — $ 442,092 $ — The September 30, 2017 Type of Fair Value Hedge Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Recognized in Income on Derivative Hedged Item Income Statement Location of Hedged Item Gain/(Loss) Amount of Gain/(Loss) Recognized in Income on Hedged Item Derivatives designated as hedging instruments: Interest Rate Contracts: Interest Rate Swaps Interest expense $ (1,413 ) Fixed rate debt Interest expense $ 1,413 Total $ (1,413 ) $ 1,413 September 30, 2016 Type of Fair Value Hedge Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Recognized in Income on Derivative Hedged Item Income Statement Location of Hedged Item Gain/(Loss) Amount of Gain/(Loss) Recognized in Income on Hedged Item Derivatives designated as hedging instruments: Interest Rate Contracts: Interest Rate Swaps Interest expense $ 4,563 Fixed rate debt Interest expense $ (4,563 ) Total $ 4,563 $ (4,563 ) The Effective Portion Ineffective Portion September 30, 2017 Type of Cash Flow Hedge Amount of Gain/(Loss) Recognized in OCI on Derivative Location of Gain/(Loss) Reclassified from Accumulated OCI into Income Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Derivatives designated as hedging instruments: Interest Rate Contracts: Forward Starting Swaps $ 5,216 Interest expense $ (14,019 ) N/A $ — Total $ 5,216 $ (14,019 ) $ — Effective Portion Ineffective Portion September 30, 2016 Type of Cash Flow Hedge Amount of Gain/(Loss) Recognized in OCI on Derivative Location of Gain/(Loss) Reclassified from Accumulated OCI into Income Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Derivatives designated as hedging instruments: Interest Rate Contracts: Forward Starting Swaps $ (4,240 ) Interest expense $ (37,262 ) N/A $ — Total $ (4,240 ) $ (37,262 ) $ — As September 30, 2017 September 30, 2017 In August 2017, the Company received $1.3 million to settle four forward starting ten-year swaps in conjunction with the issuance of $400.0 million of ten-year fixed rate public notes. The entire $1.3 million was initially deferred as a component of accumulated other comprehensive (loss) and will be recognized as a decrease to interest expense over the ten-year term of the notes.

Earning Per Share and Earnings

Earning Per Share and Earnings Per Unit	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earning Per Share And Earnings Per Unit	10. Earning Per Share and Earnings Per Equity Residential The Nine Months Ended September 30, Quarter Ended September 30, 2017 2016 2017 2016 Numerator for net income per share – basic: Income from continuing operations $ 498,297 $ 4,177,599 $ 144,196 $ 217,246 Allocation to Noncontrolling Interests – Operating Partnership, net (17,931 ) (160,437 ) (5,166 ) (8,344 ) Net (income) attributable to Noncontrolling Interests – Partially Owned Properties (2,354 ) (2,368 ) (801 ) (823 ) Preferred distributions (2,318 ) (2,318 ) (772 ) (773 ) Income from continuing operations available to Common Shares, net of Noncontrolling Interests 475,694 4,012,476 137,457 207,306 Discontinued operations, net of Noncontrolling Interests — 119 — 237 Numerator for net income per share – basic $ 475,694 $ 4,012,595 $ 137,457 $ 207,543 Numerator for net income per share – diluted: Income from continuing operations $ 498,297 $ 4,177,599 $ 144,196 $ 217,246 Net (income) attributable to Noncontrolling Interests – Partially Owned Properties (2,354 ) (2,368 ) (801 ) (823 ) Preferred distributions (2,318 ) (2,318 ) (772 ) (773 ) Income from continuing operations available to Common Shares 493,625 4,172,913 142,623 215,650 Discontinued operations, net — 124 — 246 Numerator for net income per share – diluted $ 493,625 $ 4,173,037 $ 142,623 $ 215,896 Denominator for net income per share – basic and diluted: Denominator for net income per share – basic 366,809 364,917 366,996 365,109 Effect of dilutive securities: OP Units 12,907 13,828 12,910 13,899 Long-term compensation shares/units 2,924 3,539 3,039 3,365 Denominator for net income per share – diluted 382,640 382,284 382,945 382,373 Net income per share – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per share – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56 Net income per share – basic: Income from continuing operations available to Common Shares, net of Noncontrolling Interests $ 1.30 $ 11.00 $ 0.37 $ 0.57 Discontinued operations, net of Noncontrolling Interests — — — — Net income per share – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per share – diluted: Income from continuing operations available to Common Shares $ 1.29 $ 10.92 $ 0.37 $ 0.56 Discontinued operations, net — — — — Net income per share – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56 ERP Operating Limited Partnership The following tables set forth the computation of net income per Unit – basic and net income per Unit – diluted for the Operating Partnership (amounts in thousands except per Unit amounts): Nine Months Ended September 30, Quarter Ended September 30, 2017 2016 2017 2016 Numerator for net income per Unit – basic and diluted: Income from continuing operations $ 498,297 $ 4,177,599 $ 144,196 $ 217,246 Net (income) attributable to Noncontrolling Interests – Partially Owned Properties (2,354 ) (2,368 ) (801 ) (823 ) Allocation to Preference Units (2,318 ) (2,318 ) (772 ) (773 ) Income from continuing operations available to Units 493,625 4,172,913 142,623 215,650 Discontinued operations, net — 124 — 246 Numerator for net income per Unit – basic and diluted $ 493,625 $ 4,173,037 $ 142,623 $ 215,896 Denominator for net income per Unit – basic and diluted: Denominator for net income per Unit – basic 379,716 378,745 379,906 379,008 Effect of dilutive securities: Dilution for Units issuable upon assumed exercise/vesting of the Company’s long-term compensation shares/units 2,924 3,539 3,039 3,365 Denominator for net income per Unit – diluted 382,640 382,284 382,945 382,373 Net income per Unit – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per Unit – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56 Net income per Unit – basic: Income from continuing operations available to Units $ 1.30 $ 11.00 $ 0.37 $ 0.57 Discontinued operations, net — — — — Net income per Unit – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per Unit – diluted: Income from continuing operations available to Units $ 1.29 $ 10.92 $ 0.37 $ 0.56 Discontinued operations, net — — — — Net income per Unit – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56

Individually Significant Dispos

Individually Significant Dispositions	9 Months Ended
	Sep. 30, 2017
Discontinued Operations And Disposal Groups [Abstract]
Individually Significant Dispositions	11. Individually The Company executed an agreement with controlled affiliates of Starwood Capital Group ("Starwood") on October 23, 2015 to sell a portfolio of 72 operating properties consisting of 23,262 apartment units located in five markets across the United States for $5.365 billion (the "Starwood Transaction" or “Starwood Portfolio”). The Starwood Portfolio represented substantially all of the assets in the Company’s South Florida and Denver markets and certain suburban assets in the Washington D.C., Seattle and Los Angeles markets. On January 26 and 27, 2016, the Company closed on the sale of the entire portfolio described above. The Company concluded that the Starwood Transaction did not qualify for discontinued operations reporting as it did not represent a strategic shift that had a major effect on the Company’s operations and financial results. The Company has been investing only in its six coastal markets (Boston, New York, Washington D.C., Southern California, San Francisco and Seattle) and has not been acquiring or developing any new assets in its other markets. Over the past several years, the Company has been repositioning its portfolio by selling its suburban assets located in markets outside its six core coastal markets. The sale of the Starwood Portfolio represented the continuation of the above strategy. However, the Company concluded that the Starwood Transaction did qualify as an individually significant component of the Company as the amount received upon disposal exceeded 10% of total assets, and NOI (see definition in Note 13) of the Starwood Portfolio represented approximately 1.6% of consolidated NOI (for the approximate one-month period owned in 2016) for the nine months ended September 30, 2016 and approximately 15.7% of consolidated NOI for the year ended December 31, 2015. As a result, the following table summarizes the results of operations attributable to the Starwood Transaction for the nine months and quarter ended September 30, 2016 (amounts in thousands): Nine Months Ended Quarter Ended September 30, 2016 September 30, 2016 REVENUES Rental income $ 30,660 $ 239 Total revenues 30,660 239 EXPENSES Property and maintenance 7,839 (84 ) Real estate taxes and insurance 2,933 1 Property management 2 — General and administrative 19 4 Total expenses 10,793 (79 ) Operating income 19,867 318 Interest and other income 21 10 Interest: Expense incurred, net (380 ) (6 ) Amortization of deferred financing costs (707 ) — Income and other tax (expense) benefit (1 ) — Net gain (loss) on sales of real estate properties 3,161,097 (103 ) Income from operations attributable to controlling interests – Operating Partnership 3,179,897 219 Income from operations attributable to Noncontrolling Interests – Operating Partnership (122,146 ) (8 ) Income from operations attributable to controlling interests – Company $ 3,057,751 $ 211

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments And Contingencies [Abstract]
Commitments and Contingencies	12. The Company, as an owner of real estate, is subject to various Federal, state and local environmental laws. Compliance by the Company with existing laws has not had a material adverse effect on the Company. However, the Company cannot predict the impact of new or changed laws or regulations on its current properties or on properties that it may acquire in the future. As of September 30, 2017, the Company does have environmental reserves totaling approximately $5.7 million related to two of its properties. The The Company does not believe there is any other litigation pending or threatened against it that, individually or in the aggregate, may reasonably be expected to have a material adverse effect on the Company. As of September 30, 2017, the Company has four wholly owned projects totaling 1,285 apartment units in various stages of development with commitments to fund of approximately $127.3 million and estimated completion dates ranging through September 30, 2019, as well as other completed development projects that are in various stages of lease up or are stabilized. As September 30, 2017

Reportable Segments

Reportable Segments	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Reportable Segments	13. Reportable Operating segments are defined as components of an enterprise that engage in business activities from which they may earn revenues and incur expenses and about which discrete financial information is available that is evaluated regularly by the chief The Company’s primary business is the acquisition, development and management of multifamily residential properties, which includes the generation of rental and other related income through the leasing of apartment units to residents. The chief operating decision maker evaluates the Company's operating performance geographically by market and both on a same store and non-same store basis. The Company’s same store operating segments located in its coastal markets represent its reportable segments. The Company's operating segments located in its other markets (Phoenix) that are not material have also been included in the tables presented below. The Company’s fee and asset management and development activities are other business activities that do not constitute an operating segment and as such, have been aggregated in the "Other" category in the tables presented below. All The primary financial measure for the Company’s rental real estate segment is net operating income (“NOI”), which represents The Nine Months Ended September 30, Quarter Ended September 30, 2017 2016 2017 2016 Rental income $ 1,840,170 $ 1,816,960 $ 623,951 $ 605,856 Property and maintenance expense (306,645 ) (309,688 ) (104,721 ) (104,216 ) Real estate taxes and insurance expense (253,318 ) (238,954 ) (84,087 ) (81,343 ) Total operating expenses (559,963 ) (548,642 ) (188,808 ) (185,559 ) Net operating income $ 1,280,207 $ 1,268,318 $ 435,143 $ 420,297 The following tables present NOI for each segment from our rental real estate specific to continuing operations for the nine months and quarters ended September 30, 2017 and 2016, September 30, 2017 Nine Months Ended September 30, 2017 Nine Months Ended September 30, 2016 Rental Income Operating Expenses NOI Rental Income Operating Expenses NOI Same store (1) Los Angeles $ 296,345 $ 83,927 $ 212,418 $ 285,463 $ 83,459 $ 202,004 Orange County 66,081 16,355 49,726 63,005 15,529 47,476 San Diego 66,052 17,386 48,666 63,171 16,884 46,287 Subtotal - Southern California 428,478 117,668 310,810 411,639 115,872 295,767 Washington DC 322,307 98,043 224,264 317,879 95,187 222,692 New York 345,656 126,226 219,430 345,434 120,390 225,044 San Francisco 283,654 69,053 214,601 277,666 68,246 209,420 Boston 170,545 47,538 123,007 168,118 47,308 120,810 Seattle 133,279 37,205 96,074 125,910 34,979 90,931 Other Markets 1,384 499 885 1,342 428 914 Total same store 1,685,303 496,232 1,189,071 1,647,988 482,410 1,165,578 Non-same store/other (2) (3) Non-same store 144,975 53,367 91,608 78,287 29,173 49,114 Other (3) 9,892 10,364 (472 ) 90,685 37,059 53,626 Total non-same store/other 154,867 63,731 91,136 168,972 66,232 102,740 Totals $ 1,840,170 $ 559,963 $ 1,280,207 $ 1,816,960 $ 548,642 $ 1,268,318 (1) For the nine months ended September 30, 2017 and 2016, same store primarily includes all properties acquired or completed that were stabilized prior to January 1, 2016, less properties subsequently sold, which represented 70,285 apartment (2) For the nine months ended September 30, 2017 and 2016, non-same store primarily includes properties acquired after January 1, 2016, plus any properties in lease-up and not stabilized as of January 1, (3) Other includes development, other corporate operations and operations prior to sale for properties sold from 2014 through 2017 that do not meet the discontinued operations Quarter Ended September 30, 2017 Quarter Ended September 30, 2016 Rental Income Operating Expenses NOI Rental Income Operating Expenses NOI Same store (1) Los Angeles $ 102,566 $ 27,768 $ 74,798 $ 98,542 $ 29,362 $ 69,180 Orange County 22,427 5,500 16,927 21,455 5,362 16,093 San Diego 22,432 5,867 16,565 21,516 5,740 15,776 Subtotal - Southern California 147,425 39,135 108,290 141,513 40,464 101,049 New York 125,351 46,219 79,132 124,709 44,223 80,486 Washington DC 108,763 33,459 75,304 107,340 32,817 74,523 San Francisco 98,805 24,875 73,930 97,259 24,487 72,772 Boston 57,071 16,351 40,720 56,368 16,399 39,969 Seattle 49,268 13,647 35,621 46,948 12,493 34,455 Other Markets 459 158 301 457 136 321 Total same store 587,142 173,844 413,298 574,594 171,019 403,575 Non-same store/other (2) (3) Non-same store 33,974 10,371 23,603 14,128 6,120 8,008 Other (3) 2,835 4,593 (1,758 ) 17,134 8,420 8,714 Total non-same store/other 36,809 14,964 21,845 31,262 14,540 16,722 Totals $ 623,951 $ 188,808 $ 435,143 $ 605,856 $ 185,559 $ 420,297 (1) For the quarters ended September 30, 2017 and 2016, same store primarily includes all properties acquired or completed that were stabilized prior to July 1, 2016, less properties subsequently sold, which represented 72,049 apartment (2) For the quarters ended September 30, 2017 and 2016, non-same store primarily includes properties acquired after July 1, 2016, plus any properties in lease-up and not stabilized as of July 1, (3) Other includes development, other corporate operations and operations prior to sale for properties sold from 2014 through 2017 that do not meet the discontinued operations Nine Months Ended September 30, Total Assets Capital Expenditures Same store (1) Los Angeles $ 2,620,672 $ 18,952 Orange County 330,580 6,671 San Diego 425,241 3,776 Subtotal - Southern California 3,376,493 29,399 Washington DC 3,836,992 26,308 New York 4,181,890 23,547 San Francisco 2,480,069 25,896 Boston 1,670,467 18,906 Seattle 1,172,356 15,499 Other Markets 12,778 83 Total same store 16,731,045 139,638 Non-same store/other (2) (3) Non-same store 3,080,697 3,206 Other (3) 886,091 414 Total non-same store/other 3,966,788 3,620 Totals $ 20,697,833 $ 143,258 (1) Same store primarily includes all properties acquired or completed that were stabilized prior to January 1, 2016, less properties subsequently sold, which represented 70,285 apartment (2) Non-same store primarily includes properties acquired after January 1, 2016, plus any properties in lease-up and not stabilized as of January 1, (3) Other includes development, other corporate operations and capital expenditures for properties

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Subsequent to September 30, 2017, the Company repaid $103.9 million of 7.125% unsecured notes at maturity.

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2017
Summary Of Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) and certain reclassifications considered necessary for a fair presentation have been included. Certain reclassifications have been made to the prior period financial statements in order to conform to the current year presentation. These reclassifications did not have an impact on net income previously reported. Operating results for the nine months ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017. In preparation of the Company’s financial statements in conformity with accounting principles generally accepted in the United States, management makes estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. The balance sheets at December 31, 2016 have been derived from the audited financial statements at that date but do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. For further information, including definitions of capitalized terms not defined herein, refer to the consolidated financial statements and footnotes thereto included in the Company’s and the Operating Partnership's Annual Report on Form 10-K for the year ended December 31, 2016.
Income and Other Taxes	Income and Other Taxes Due to the structure of EQR as a REIT and the nature of the operations of its operating properties, no provision for federal income taxes has been made at the EQR level. In addition, ERPOP generally is not liable for federal income taxes as the partners recognize their proportionate share of income or loss in their tax returns; therefore no provision for federal income taxes has been made at the ERPOP level. Historically, the Company has generally only incurred certain state and local income, excise and franchise taxes. The Company has elected Taxable REIT Subsidiary (“TRS”) status for certain of its corporate subsidiaries and as a result, these entities will incur both federal and state income taxes on any taxable income of such entities after consideration of any net operating losses. 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 bases. These assets and liabilities are measured using enacted tax rates for which the temporary differences are expected to be recovered or settled. The effects of changes in tax rates on deferred tax assets and liabilities are recognized in earnings in the period enacted. The Company’s deferred tax assets were generally the result of tax affected suspended interest deductions, net operating losses, differing depreciable lives on capitalized assets and the timing of expense recognition for certain accrued liabilities. As of September 30, 2017, the Company has elected REIT status for its primary TRS upon filing the 2016 tax return in the third quarter of 2017, with the election retroactive to January 1, 2016. As a result, the Company wrote-off its deferred tax assets, which were fully reserved, as of September 30, 2017.
Recently Issued and Adopted Accounting Pronouncements	Recently Issued Accounting Pronouncements In "FASB") Revenue from Contracts with Customers any, In FASB In • Lessors – Leases will be accounted for using an approach that is substantially equivalent to existing guidance for operating, sales-type and financing leases, but aligned with the new revenue recognition standard. Lessors will be required to allocate lease payments to separate lease and non-lease components of each lease agreement, with the non-lease components evaluated under the new revenue recognition standard. • Lessees – Leases will be accounted for using a dual approach, classifying leases as either operating or finance based on the principle of whether or not the lease is effectively a financed purchase of the leased asset by the lessee. This classification will determine whether the lease expense is recognized on a straight-line basis over the term of the lease (for operating leases) or based on an effective interest method with a front-loaded expense recognition (for finance leases). A lessee is also required to record a right-of-use asset and a lease liability on its balance sheet for all leases with a term of greater than 12 months regardless of their classification as operating or finance leases. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases. The new standard will be effective for the Company beginning on January 1, 2019, with early adoption permitted, though the Company currently anticipates adopting the new standard on the effective date. The new standard must be adopted using a modified retrospective method, which requires application of the new guidance at the beginning of the earliest comparative period presented and provides for certain practical expedients, which the Company currently anticipates electing. The Company anticipates that its residential and retail/commercial leases where it is the lessor will continue to be accounted for as operating leases under the new standard. Therefore, the Company does not currently anticipate significant changes in the accounting for its lease revenues. The Company is also the lessee under various corporate office and ground leases, which it will be required to recognize right of use assets and related lease liabilities on its consolidated balance sheets upon adoption. The Company currently anticipates that its corporate office leases where it is the lessee will continue to be accounted for as operating leases under the new standard. Based on its anticipated election of the practical expedients, the Company would not be required to reassess the classification of existing ground leases and therefore these leases would continue to be accounted for as operating leases. However, in the event we modify existing ground leases and/or enter into new ground leases after adoption of the new standard, such leases will likely be classified as finance leases. The Company will continue to evaluate the impact of adopting the new leases standard on its consolidated results of operations and financial position. In June 2016, the FASB In FASB • Cash payments related to debt prepayments or extinguishment costs are to be classified within financing • The portion of the cash payment made to settle a zero-coupon bond or a bond with an insignificant cash coupon attributable to accreted interest related to a debt discount is to be classified as a cash outflow within operating activities, and the portion attributable to the principal is to be classified within financing • Insurance settlement proceeds are to be classified based on the nature of the • Companies must elect to classify distributions received from equity method investees using either a cumulative earnings approach or a look-through approach and the election must be disclosed; • Restricted Total The The Company does not expect overall cash flows to change; however, there will be material changes between cash flow classifications due to the substantial debt prepayment penalties that the Company has incurred in the comparative period. In FASB clarifies the accounting treatment for partial sales of nonfinancial assets (i.e. real estate). The standard clarifies that partial sales transactions include contributions of nonfinancial assets to a joint venture or other noncontrolled investee. Companies must recognize a full gain or loss on transfers of nonfinancial assets to equity method investees. The standard requires companies to derecognize distinct nonfinancial assets or distinct in substance nonfinancial assets in partial sale transactions when it does not have a controlling financial interest in the legal entity that holds the asset and transfers control of the asset. Once the distinct nonfinancial asset is transferred, the company is required to measure any non-controlling interest it receives or retains at fair value and recognize a full gain or loss on the transaction. If a company transfers ownership interests in a consolidated subsidiary and continues to maintain a controlling financial interest, the company does not derecognize the assets or liabilities, and accounts for the transaction as an equity transaction and no gain or loss is recognized. The new standard will be effective for the Company beginning on January 1, 2018 and early adoption was permitted beginning on January 1, 2017. The Company anticipates adopting the new standard concurrently with the new revenue recognition standard. The new standard may be applied retrospectively to each prior period presented or prospectively with the cumulative effect recognized as of the date of adoption. The Company has not had a partial sale of nonfinancial assets in the current or comparative periods. Therefore, the Company does not currently believe that the adoption of this standard will have a material impact on its consolidated results of operations and financial position. In August 2017, the FASB issued a final standard which makes changes to the hedge accounting model to enable entities to better portray their risk management activities in the financial statements. The new standard expands an entity’s ability to hedge nonfinancial and financial risk components, reduces complexity in fair value hedges of interest rate risk and eases certain documentation and assessment requirements. The new standard also eliminates the requirement to separately measure and report hedge ineffectiveness and generally requires the entire change in the fair value of any hedging instrument to be presented in the same income statement line as the hedged instrument. The new standard will be effective for the Company beginning on January 1, 2019 and early adoption is permitted. The Company is currently evaluating the impact of adopting the new standard on its consolidated results of operations and financial position. Recently Adopted Accounting Pronouncements In FASB Generally, In FASB In FASB
Other	Other The Company is the controlling partner in various consolidated partnerships owning 17 properties and 3,215 apartment units having a noncontrolling interest book value of $6.2 million at September 30, 2017. The Company is required to make certain disclosures regarding noncontrolling interests in consolidated limited-life subsidiaries. Of the consolidated entities described above, the Company is the controlling partner in limited-life partnerships owning four properties having a noncontrolling interest deficit balance of $7.3 million. These four partnership agreements contain provisions that require the partnerships to be liquidated through the sale of their assets upon reaching a date specified in each respective partnership agreement. The Company, as controlling partner, has an obligation to cause the property owning partnerships to distribute the proceeds of liquidation to the Noncontrolling Interests in these Partially Owned Properties only to the extent that the net proceeds received by the partnerships from the sale of their assets warrant a distribution based on the partnership agreements. As of September 30, 2017, the Company estimates the value of Noncontrolling Interest distributions for these four properties would have been approximately $65.8 million (“Settlement Value”) had the partnerships been liquidated. This Settlement Value is based on estimated third party consideration realized by the partnerships upon disposition of the four Partially Owned Properties and is net of all other assets and liabilities, including yield maintenance on the mortgages encumbering the properties, that would have been due on had those mortgages been prepaid. Due to, among other things, the inherent uncertainty in the sale of real estate assets, the amount of any potential distribution to the Noncontrolling Interests in the Company's Partially Owned Properties is subject to change. To the extent that the partnerships' underlying assets are worth less than the underlying liabilities, the Company has no obligation to remit any consideration to the Noncontrolling Interests in these Partially Owned Properties

Business (Tables)

Business (Tables)	9 Months Ended
	Sep. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Ownership Breakdown	The ownership breakdown includes (table does not include various uncompleted development properties): Properties Apartment Units Wholly Owned Properties 283 73,289 Master-Leased Properties – Consolidated 3 853 Partially Owned Properties – Consolidated 17 3,215 Partially Owned Properties – Unconsolidated 2 945 305 78,302

Equity, Capital and Other Int29

Equity, Capital and Other Interests (Tables)	9 Months Ended
	Sep. 30, 2017
Changes in Issued and Outstanding Common Shares and Units	The following tables present the changes in the Company’s issued and outstanding Common Shares and “Units” (which includes OP Units and restricted units) for the nine months ended September 30, 2017: 2017 Common Shares Common Shares outstanding at January 1, 365,870,924 Common Shares Issued: Conversion of OP Units 1,107,735 Exercise of share options 343,527 Employee Share Purchase Plan (ESPP) 54,843 Restricted share grants, net 85,451 Common Shares Outstanding at September 30, 367,462,480 Units Units outstanding at January 1, 14,626,075 Restricted unit grants, net 291,647 Conversion of OP Units to Common Shares (1,107,735 ) Units outstanding at September 30, 13,809,987 Total Common Shares and Units outstanding at September 30, 381,272,467 Units Ownership Interest in Operating Partnership 3.6 %
Changes in Redemption Value of Redeemable Noncontrolling Interests and Limited Partners Interest	The 2017 Balance at January 1, $ 442,092 Change in market value (29,551 ) Change in carrying value (32,000 ) Balance at September 30, $ 380,541
Issued and Outstanding Preferred Shares and Preference Units	The Amounts in thousands Annual Call Dividend per September 30, December 31, Date (1) Share (2) 2017 2016 Preferred Shares of beneficial interest, $0.01 par value; 100,000,000 shares authorized: 8.29% Series K Cumulative Redeemable Preferred; liquidation value $50 per share; 745,600 shares issued and outstanding at September 30, 2017 and December 31, 2016 12/10/26 $ 4.145 $ 37,280 $ 37,280 $ 37,280 $ 37,280 (1) On or after the call date, redeemable preferred shares may be redeemed for cash at the option of the Company, in whole or in part, at a redemption price equal to the liquidation price per share, plus accrued and unpaid distributions, if any. (2) Dividends on Preferred Shares are payable quarterly.
ERPOP [Member]
Changes in Issued and Outstanding Common Shares and Units	The following tables present the changes in the Operating Partnership’s issued and outstanding Units and in the limited partners’ Units for the nine months ended September 30, 2017: 2017 General and Limited Partner Units General and Limited Partner Units outstanding at January 1, 380,496,999 Issued to General Partner: Exercise of EQR share options 343,527 EQR’s Employee Share Purchase Plan (ESPP) 54,843 EQR's restricted share grants, net 85,451 Issued to Limited Partners: Restricted unit grants, net 291,647 General and Limited Partner Units outstanding at September 30, 381,272,467 Limited Partner Units Limited Partner Units outstanding at January 1, 14,626,075 Limited Partner restricted unit grants, net 291,647 Conversion of Limited Partner OP Units to EQR Common Shares (1,107,735 ) Limited Partner Units outstanding at September 30, 13,809,987 Limited Partner Units Ownership Interest in Operating Partnership 3.6 %
Changes in Redemption Value of Redeemable Noncontrolling Interests and Limited Partners Interest	The following table presents the changes in the redemption value of the Redeemable Limited Partners for the nine months ended September 30, 2017 (amounts in thousands): 2017 Balance at January 1, $ 442,092 Change in market value (29,551 ) Change in carrying value (32,000 ) Balance at September 30, $ 380,541
Issued and Outstanding Preferred Shares and Preference Units	The December 31, 2016 Amounts in thousands Annual Call Dividend Per September 30, December 31, Date (1) Unit (2) 2017 2016 Preference Units: 8.29% Series K Cumulative Redeemable Preference Units; liquidation value $50 per unit; 745,600 units issued and outstanding at September 30, 2017 and December 31, 2016 12/10/26 $ 4.145 $ 37,280 $ 37,280 $ 37,280 $ 37,280 (1) On or after the call date, redeemable preference units may be redeemed for cash at the option of the Operating Partnership, in whole or in part, at a redemption price equal to the liquidation price per unit, plus accrued and unpaid distributions, if any, in conjunction with the concurrent redemption of the corresponding Company Preferred Shares. (2) Dividends on Preference Units are payable quarterly.

Real Estate and Lease Intangi30

Real Estate and Lease Intangibles (Tables)	9 Months Ended
	Sep. 30, 2017
Real Estate [Abstract]
Summary of Carrying Amounts of Investment in Real Estate	The following table summarizes the carrying amounts for the Company’s investment in real estate (at cost) as of September 30, 2017 and December 31, 2016 (amounts in thousands): September 30, 2017 December 31, 2016 Land $ 5,985,004 $ 5,899,862 Depreciable property: Buildings and improvements 17,601,348 16,913,430 Furniture, fixtures and equipment 1,500,963 1,346,300 In-Place lease intangibles 469,091 470,849 Projects under development: Land 61,047 115,876 Construction-in-progress 232,017 521,292 Land held for development: Land 63,439 84,440 Construction-in-progress 35,634 34,376 Investment in real estate 25,948,543 25,386,425 Accumulated depreciation (5,849,110 ) (5,360,389 ) Investment in real estate, net $ 20,099,433 $ 20,026,036
Summary of Carrying Amounts of Above and Below Market Ground And Retail Lease Intangibles	The following table summarizes the carrying amounts for the Company's above and below market ground and retail lease intangibles as of September 30, 2017 and December 31, 2016 (amounts in thousands): Description Balance Sheet Location September 30, 2017 December 31, 2016 Assets Ground lease intangibles – below market Other Assets $ 191,918 $ 178,251 Retail lease intangibles – above market Other Assets 1,260 1,260 Lease intangible assets 193,178 179,511 Accumulated amortization (21,305 ) (17,972 ) Lease intangible assets, net $ 171,873 $ 161,539 Liabilities Ground lease intangibles – above market Other Liabilities $ 2,400 $ 2,400 Retail lease intangibles – below market Other Liabilities 5,270 5,270 Lease intangible liabilities 7,670 7,670 Accumulated amortization (5,113 ) (4,509 ) Lease intangible liabilities, net $ 2,557 $ 3,161
Summary of the Effect of the Amortization for Above and Below Market Ground and Retail Lease Intangibles	The following table provides a summary of the effect of the amortization for above and below market ground and retail lease intangibles on Nine Months Ended Quarter Ended September 30, September 30, Description Income Statement Location 2017 2016 2017 2016 Ground lease intangible amortization Property and Maintenance $ (3,253 ) $ (3,241 ) $ (1,092 ) $ (1,080 ) Retail lease intangible amortization Rental Income 524 675 80 222 Total amortization of above/below market lease intangibles $ (2,729 ) $ (2,566 ) $ (1,012 ) $ (858 )
Summary of Aggregate Amortization for Above and Below Market Ground And Retail Lease Intangibles	The following table provides a summary of the aggregate amortization for above and below market ground and retail lease intangibles for each of the next five years (amounts in thousands): Remaining 2017 2018 2019 2020 2021 2022 Ground lease intangibles $ (1,116 ) $ (4,463 ) $ (4,463 ) $ (4,463 ) $ (4,463 ) $ (4,463 ) Retail lease intangibles 16 71 71 71 71 27 Total $ (1,100 ) $ (4,392 ) $ (4,392 ) $ (4,392 ) $ (4,392 ) $ (4,436 )
Acquired Properties From Unaffiliated Parties	During the nine months ended September 30, 2017, the Company acquired the entire equity interest in the following from unaffiliated parties (purchase price in thousands): Properties Apartment Units Purchase Price Rental Properties – Consolidated (1) 4 947 $ 468,050 Total 4 947 $ 468,050 (1) Purchase price includes an allocation of approximately $68.3 million to land, $386.2 million to depreciable property (inclusive of capitalized closing costs) and $13.7 million to ground lease intangible (included in other assets). For one of the property acquisitions, the Company owns the building and improvements and leases the land underlying the improvements under a long-term ground lease that expires in 2113. This property is consolidated and reflected as a real estate asset while the ground lease is accounted for as an operating lease.
Disposed Properties to Unaffiliated Parties	During the nine months ended September 30, 2017 , the Company disposed of the following to unaffiliated parties (sales price in thousands): Properties Apartment Units Sales Price Rental Properties – Consolidated 4 1,024 $ 319,700 Land Parcels (one) — — 33,450 Total 4 1,024 $ 353,150

Commitments To Acquire_Dispos31

Commitments To Acquire/Dispose of Real Estate (Tables)	9 Months Ended
	Sep. 30, 2017
Commitments To Acquire Dispose Of Real Estate [Abstract]
Separate Agreement to Dispose of	The Company has entered into a separate agreement to dispose of the following (sales price in thousands): Properties Apartment Units Sales Price Land Parcels (one) — — $ 2,700 Total — — $ 2,700

Investments in Partially Owne32

Investments in Partially Owned Entities (Tables)	9 Months Ended
	Sep. 30, 2017
Investments In Partially Owned Entities [Abstract]
Partially Owned Property Balance Sheet Schedule	The following tables and information summarize the Company’s investments September 30, 2017 Consolidated Unconsolidated (VIE) (Non-VIE) (VIE) (1) Total Total properties 17 2 — 2 Total apartment units 3,215 945 — 945 Balance sheet information at 9/30/2017 (at 100%): ASSETS Investment in real estate $ 648,839 $ 236,630 $ 172,995 $ 409,625 Accumulated depreciation (226,607 ) (40,840 ) (48,670 ) (89,510 ) Investment in real estate, net 422,232 195,790 124,325 320,115 Cash and cash equivalents 22,914 7,194 139 7,333 Investments in unconsolidated entities 45,035 — — — Deposits – restricted 385 258 — 258 Other assets 26,246 450 105 555 Total assets $ 516,812 $ 203,692 $ 124,569 $ 328,261 LIABILITIES AND EQUITY/CAPITAL Mortgage notes payable, net (2) $ 302,037 $ 145,424 $ — $ 145,424 Accounts payable & accrued expenses 2,975 2,644 150 2,794 Accrued interest payable 1,024 691 — 691 Other liabilities 453 308 27 335 Security deposits 2,037 488 — 488 Total liabilities 308,526 149,555 177 149,732 Noncontrolling Interests – Partially Owned Properties/Partners' equity 6,175 54,336 84,682 139,018 Company equity/General and Limited Partners' Capital 202,111 (199 ) 39,710 39,511 Total equity/capital 208,286 54,137 124,392 178,529 Total liabilities and equity/capital $ 516,812 $ 203,692 $ 124,569 $ 328,261
Partially Owned Property Income Statement Schedule	Consolidated Unconsolidated (VIE) (Non-VIE) (VIE) (1) Total Operating information for the nine months ended 9/30/2017 (at 100%): Operating revenue $ 69,917 $ 20,050 $ 3,805 $ 23,855 Operating expenses 17,056 6,746 1,573 8,319 Net operating income 52,861 13,304 2,232 15,536 Property management 2,463 584 56 640 General and administrative/other 239 1 127 128 Depreciation 15,569 7,960 4,126 12,086 Operating income (loss) 34,590 4,759 (2,077 ) 2,682 Interest and other income 45 — — — Interest: Expense incurred, net (9,977 ) (6,217 ) — (6,217 ) Amortization of deferred financing costs (203 ) (1 ) — (1 ) Income (loss) before income and other taxes and (loss) from investments in unconsolidated entities 24,455 (1,459 ) (2,077 ) (3,536 ) Income and other tax (expense) benefit (34 ) (13 ) — (13 ) (Loss) from investments in unconsolidated entities (1,155 ) — — — Net income (loss) $ 23,266 $ (1,472 ) $ (2,077 ) $ (3,549 ) (1) Includes the Company’s unconsolidated interest in an entity that owns the land underlying our Wisconsin Place apartment property and owns and operates the parking facility. This entity is excluded from the property and apartment unit count. (2) All debt is non-recourse to the Company. Note: The above tables exclude EQR's ownership interest in ERPOP, private equity fund investments, and the Company's interests in unconsolidated joint ventures established in connection with the acquisition of certain real estate related assets from Archstone Enterprise LP ("Archstone").

Deposits - Restricted and Esc33

Deposits - Restricted and Escrow Deposits - Mortgage (Tables)	9 Months Ended
	Sep. 30, 2017
Deposits Restricted [Abstract]
Restricted Deposits	The following table presents the Company’s restricted deposits as of September 30, 2017 and December 31, 2016 (amounts in thousands): September 30, 2017 December 31, 2016 Tax-deferred (1031) exchange proceeds $ — $ 38,847 Restricted deposits on real estate investments 61 733 Resident security and utility deposits 35,667 37,007 Other 911 359 Totals $ 36,639 $ 76,946
Escrow Deposits for Mortgages	The following table presents the Company’s escrow deposits for mortgages as of September 30, 2017 and December 31, 2016 (amounts in thousands): September 30, 2017 December 31, 2016 Real estate taxes and insurance $ 556 $ 2,003 Replacement reserves 7,969 3,428 Mortgage principal reserves/sinking funds 1,595 58,652 Other 852 852 Totals $ 10,972 $ 64,935

Derivative and Other Fair Val34

Derivative and Other Fair Value Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Summary of Carrying and Fair Values of Financial Instruments	The September 30, 2017 December 31, 2016 Estimated Fair Value (Level 2) Carrying Value Estimated Fair Value (Level 2) Carrying Value Mortgage notes payable, net $ 3,630,477 $ 3,619,180 $ 4,161,001 $ 4,119,181 Unsecured debt, net 5,640,095 5,373,092 5,030,330 4,868,077 Total debt, net $ 9,270,572 $ 8,992,272 $ 9,191,331 $ 8,987,258
Summary of Consolidated Derivative Instruments	The September 30, 2017 Fair Value Hedges (1) Forward Starting Swaps (2) Current Notional Balance $ 450,000 $ 250,000 Lowest Interest Rate 2.375 % 2.1478 % Highest Interest Rate 2.375 % 2.2895 % Earliest Maturity Date 2019 2028 Latest Maturity Date 2019 2029 (1) Fair Value Hedges – Converts outstanding fixed rate unsecured notes ($450.0 million 2.375% notes due July 1, 2019) to a floating interest rate of 90-Day LIBOR plus 0.61%. (2) Forward Starting Swaps – Designed to partially fix interest rates in advance of planned future debt issuances. Of the $250.0 million notional balance, $200.0 million of these swaps have mandatory counterparty terminations in 2019 and are targeted for 2018 debt issuances while $50.0 million of these swaps have mandatory counterparty terminations in 2020 and are targeted for 2019 debt issuances.
Summary of Fair Value Measurements for Each Major Category of Assets and Liabilities Measured at Fair Value on Recurring Basis	The Fair Value Measurements at Reporting Date Using Description Balance Sheet Location 9/30/2017 Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Derivatives designated as hedging instruments: Interest Rate Contracts: Fair Value Hedges Other Assets $ 444 $ — $ 444 $ — Forward Starting Swaps Other Assets 3,921 — 3,921 — Supplemental Executive Retirement Plan Other Assets 136,774 136,774 — — Total $ 141,139 $ 136,774 $ 4,365 $ — Liabilities Supplemental Executive Retirement Plan Other Liabilities $ 136,774 $ 136,774 $ — $ — Total $ 136,774 $ 136,774 $ — $ — Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners Mezzanine $ 380,541 $ — $ 380,541 $ — Fair Value Measurements at Reporting Date Using Description Balance Sheet Location 12/31/2016 Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Derivatives designated as hedging instruments: Interest Rate Contracts: Fair Value Hedges Other Assets $ 1,857 $ — $ 1,857 $ — Supplemental Executive Retirement Plan Other Assets 124,420 124,420 — — Total $ 126,277 $ 124,420 $ 1,857 $ — Liabilities Supplemental Executive Retirement Plan Other Liabilities $ 124,420 $ 124,420 $ — $ — Total $ 124,420 $ 124,420 $ — $ — Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners Mezzanine $ 442,092 $ — $ 442,092 $ —
Summary of Effect of Fair Value Hedges on the Accompanying Consolidated Statements of Operations and Comprehensive Income	The September 30, 2017 Type of Fair Value Hedge Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Recognized in Income on Derivative Hedged Item Income Statement Location of Hedged Item Gain/(Loss) Amount of Gain/(Loss) Recognized in Income on Hedged Item Derivatives designated as hedging instruments: Interest Rate Contracts: Interest Rate Swaps Interest expense $ (1,413 ) Fixed rate debt Interest expense $ 1,413 Total $ (1,413 ) $ 1,413 September 30, 2016 Type of Fair Value Hedge Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Recognized in Income on Derivative Hedged Item Income Statement Location of Hedged Item Gain/(Loss) Amount of Gain/(Loss) Recognized in Income on Hedged Item Derivatives designated as hedging instruments: Interest Rate Contracts: Interest Rate Swaps Interest expense $ 4,563 Fixed rate debt Interest expense $ (4,563 ) Total $ 4,563 $ (4,563 )
Summary of Effect of Cash Flow Hedges on the Accompanying Consolidated Statements of Operations and Comprehensive Income	The Effective Portion Ineffective Portion September 30, 2017 Type of Cash Flow Hedge Amount of Gain/(Loss) Recognized in OCI on Derivative Location of Gain/(Loss) Reclassified from Accumulated OCI into Income Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Derivatives designated as hedging instruments: Interest Rate Contracts: Forward Starting Swaps $ 5,216 Interest expense $ (14,019 ) N/A $ — Total $ 5,216 $ (14,019 ) $ — Effective Portion Ineffective Portion September 30, 2016 Type of Cash Flow Hedge Amount of Gain/(Loss) Recognized in OCI on Derivative Location of Gain/(Loss) Reclassified from Accumulated OCI into Income Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income Derivatives designated as hedging instruments: Interest Rate Contracts: Forward Starting Swaps $ (4,240 ) Interest expense $ (37,262 ) N/A $ — Total $ (4,240 ) $ (37,262 ) $ —

Earning Per Share and Earning35

Earning Per Share and Earnings Per Unit (Tables)	9 Months Ended
	Sep. 30, 2017
Schedule of Calculation of Numerator and Denominator in Earning Per Share and Earnings Per Unit	The Nine Months Ended September 30, Quarter Ended September 30, 2017 2016 2017 2016 Numerator for net income per share – basic: Income from continuing operations $ 498,297 $ 4,177,599 $ 144,196 $ 217,246 Allocation to Noncontrolling Interests – Operating Partnership, net (17,931 ) (160,437 ) (5,166 ) (8,344 ) Net (income) attributable to Noncontrolling Interests – Partially Owned Properties (2,354 ) (2,368 ) (801 ) (823 ) Preferred distributions (2,318 ) (2,318 ) (772 ) (773 ) Income from continuing operations available to Common Shares, net of Noncontrolling Interests 475,694 4,012,476 137,457 207,306 Discontinued operations, net of Noncontrolling Interests — 119 — 237 Numerator for net income per share – basic $ 475,694 $ 4,012,595 $ 137,457 $ 207,543 Numerator for net income per share – diluted: Income from continuing operations $ 498,297 $ 4,177,599 $ 144,196 $ 217,246 Net (income) attributable to Noncontrolling Interests – Partially Owned Properties (2,354 ) (2,368 ) (801 ) (823 ) Preferred distributions (2,318 ) (2,318 ) (772 ) (773 ) Income from continuing operations available to Common Shares 493,625 4,172,913 142,623 215,650 Discontinued operations, net — 124 — 246 Numerator for net income per share – diluted $ 493,625 $ 4,173,037 $ 142,623 $ 215,896 Denominator for net income per share – basic and diluted: Denominator for net income per share – basic 366,809 364,917 366,996 365,109 Effect of dilutive securities: OP Units 12,907 13,828 12,910 13,899 Long-term compensation shares/units 2,924 3,539 3,039 3,365 Denominator for net income per share – diluted 382,640 382,284 382,945 382,373 Net income per share – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per share – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56 Net income per share – basic: Income from continuing operations available to Common Shares, net of Noncontrolling Interests $ 1.30 $ 11.00 $ 0.37 $ 0.57 Discontinued operations, net of Noncontrolling Interests — — — — Net income per share – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per share – diluted: Income from continuing operations available to Common Shares $ 1.29 $ 10.92 $ 0.37 $ 0.56 Discontinued operations, net — — — — Net income per share – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56
ERPOP [Member]
Schedule of Calculation of Numerator and Denominator in Earning Per Share and Earnings Per Unit	The following tables set forth the computation of net income per Unit – basic and net income per Unit – diluted for the Operating Partnership (amounts in thousands except per Unit amounts): Nine Months Ended September 30, Quarter Ended September 30, 2017 2016 2017 2016 Numerator for net income per Unit – basic and diluted: Income from continuing operations $ 498,297 $ 4,177,599 $ 144,196 $ 217,246 Net (income) attributable to Noncontrolling Interests – Partially Owned Properties (2,354 ) (2,368 ) (801 ) (823 ) Allocation to Preference Units (2,318 ) (2,318 ) (772 ) (773 ) Income from continuing operations available to Units 493,625 4,172,913 142,623 215,650 Discontinued operations, net — 124 — 246 Numerator for net income per Unit – basic and diluted $ 493,625 $ 4,173,037 $ 142,623 $ 215,896 Denominator for net income per Unit – basic and diluted: Denominator for net income per Unit – basic 379,716 378,745 379,906 379,008 Effect of dilutive securities: Dilution for Units issuable upon assumed exercise/vesting of the Company’s long-term compensation shares/units 2,924 3,539 3,039 3,365 Denominator for net income per Unit – diluted 382,640 382,284 382,945 382,373 Net income per Unit – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per Unit – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56 Net income per Unit – basic: Income from continuing operations available to Units $ 1.30 $ 11.00 $ 0.37 $ 0.57 Discontinued operations, net — — — — Net income per Unit – basic $ 1.30 $ 11.00 $ 0.37 $ 0.57 Net income per Unit – diluted: Income from continuing operations available to Units $ 1.29 $ 10.92 $ 0.37 $ 0.56 Discontinued operations, net — — — — Net income per Unit – diluted $ 1.29 $ 10.92 $ 0.37 $ 0.56

Individually Significant Disp36

Individually Significant Dispositions (Tables)	9 Months Ended
	Sep. 30, 2017
Starwood Portfolio [Member] | Disposal Group, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Schedule of Results of Operations Attributable to Starwood Transaction	As a result, the following table summarizes the results of operations attributable to the Starwood Transaction for the nine months and quarter ended September 30, 2016 (amounts in thousands): Nine Months Ended Quarter Ended September 30, 2016 September 30, 2016 REVENUES Rental income $ 30,660 $ 239 Total revenues 30,660 239 EXPENSES Property and maintenance 7,839 (84 ) Real estate taxes and insurance 2,933 1 Property management 2 — General and administrative 19 4 Total expenses 10,793 (79 ) Operating income 19,867 318 Interest and other income 21 10 Interest: Expense incurred, net (380 ) (6 ) Amortization of deferred financing costs (707 ) — Income and other tax (expense) benefit (1 ) — Net gain (loss) on sales of real estate properties 3,161,097 (103 ) Income from operations attributable to controlling interests – Operating Partnership 3,179,897 219 Income from operations attributable to Noncontrolling Interests – Operating Partnership (122,146 ) (8 ) Income from operations attributable to controlling interests – Company $ 3,057,751 $ 211

Reportable Segments (Tables)

Reportable Segments (Tables)	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Schedule of Reconciliation of NOI from Rental Real Estate Specific to Continuing Operations	The Nine Months Ended September 30, Quarter Ended September 30, 2017 2016 2017 2016 Rental income $ 1,840,170 $ 1,816,960 $ 623,951 $ 605,856 Property and maintenance expense (306,645 ) (309,688 ) (104,721 ) (104,216 ) Real estate taxes and insurance expense (253,318 ) (238,954 ) (84,087 ) (81,343 ) Total operating expenses (559,963 ) (548,642 ) (188,808 ) (185,559 ) Net operating income $ 1,280,207 $ 1,268,318 $ 435,143 $ 420,297
Schedule of NOI for Each Segment from Rental Real Estate Specific to Continuing Operations	The following tables present NOI for each segment from our rental real estate specific to continuing operations for the nine months and quarters ended September 30, 2017 and 2016, September 30, 2017 Nine Months Ended September 30, 2017 Nine Months Ended September 30, 2016 Rental Income Operating Expenses NOI Rental Income Operating Expenses NOI Same store (1) Los Angeles $ 296,345 $ 83,927 $ 212,418 $ 285,463 $ 83,459 $ 202,004 Orange County 66,081 16,355 49,726 63,005 15,529 47,476 San Diego 66,052 17,386 48,666 63,171 16,884 46,287 Subtotal - Southern California 428,478 117,668 310,810 411,639 115,872 295,767 Washington DC 322,307 98,043 224,264 317,879 95,187 222,692 New York 345,656 126,226 219,430 345,434 120,390 225,044 San Francisco 283,654 69,053 214,601 277,666 68,246 209,420 Boston 170,545 47,538 123,007 168,118 47,308 120,810 Seattle 133,279 37,205 96,074 125,910 34,979 90,931 Other Markets 1,384 499 885 1,342 428 914 Total same store 1,685,303 496,232 1,189,071 1,647,988 482,410 1,165,578 Non-same store/other (2) (3) Non-same store 144,975 53,367 91,608 78,287 29,173 49,114 Other (3) 9,892 10,364 (472 ) 90,685 37,059 53,626 Total non-same store/other 154,867 63,731 91,136 168,972 66,232 102,740 Totals $ 1,840,170 $ 559,963 $ 1,280,207 $ 1,816,960 $ 548,642 $ 1,268,318 (1) For the nine months ended September 30, 2017 and 2016, same store primarily includes all properties acquired or completed that were stabilized prior to January 1, 2016, less properties subsequently sold, which represented 70,285 apartment (2) For the nine months ended September 30, 2017 and 2016, non-same store primarily includes properties acquired after January 1, 2016, plus any properties in lease-up and not stabilized as of January 1, (3) Other includes development, other corporate operations and operations prior to sale for properties sold from 2014 through 2017 that do not meet the discontinued operations Quarter Ended September 30, 2017 Quarter Ended September 30, 2016 Rental Income Operating Expenses NOI Rental Income Operating Expenses NOI Same store (1) Los Angeles $ 102,566 $ 27,768 $ 74,798 $ 98,542 $ 29,362 $ 69,180 Orange County 22,427 5,500 16,927 21,455 5,362 16,093 San Diego 22,432 5,867 16,565 21,516 5,740 15,776 Subtotal - Southern California 147,425 39,135 108,290 141,513 40,464 101,049 New York 125,351 46,219 79,132 124,709 44,223 80,486 Washington DC 108,763 33,459 75,304 107,340 32,817 74,523 San Francisco 98,805 24,875 73,930 97,259 24,487 72,772 Boston 57,071 16,351 40,720 56,368 16,399 39,969 Seattle 49,268 13,647 35,621 46,948 12,493 34,455 Other Markets 459 158 301 457 136 321 Total same store 587,142 173,844 413,298 574,594 171,019 403,575 Non-same store/other (2) (3) Non-same store 33,974 10,371 23,603 14,128 6,120 8,008 Other (3) 2,835 4,593 (1,758 ) 17,134 8,420 8,714 Total non-same store/other 36,809 14,964 21,845 31,262 14,540 16,722 Totals $ 623,951 $ 188,808 $ 435,143 $ 605,856 $ 185,559 $ 420,297 (1) For the quarters ended September 30, 2017 and 2016, same store primarily includes all properties acquired or completed that were stabilized prior to July 1, 2016, less properties subsequently sold, which represented 72,049 apartment (2) For the quarters ended September 30, 2017 and 2016, non-same store primarily includes properties acquired after July 1, 2016, plus any properties in lease-up and not stabilized as of July 1, (3) Other includes development, other corporate operations and operations prior to sale for properties sold from 2014 through 2017 that do not meet the discontinued operations Nine Months Ended September 30, Total Assets Capital Expenditures Same store (1) Los Angeles $ 2,620,672 $ 18,952 Orange County 330,580 6,671 San Diego 425,241 3,776 Subtotal - Southern California 3,376,493 29,399 Washington DC 3,836,992 26,308 New York 4,181,890 23,547 San Francisco 2,480,069 25,896 Boston 1,670,467 18,906 Seattle 1,172,356 15,499 Other Markets 12,778 83 Total same store 16,731,045 139,638 Non-same store/other (2) (3) Non-same store 3,080,697 3,206 Other (3) 886,091 414 Total non-same store/other 3,966,788 3,620 Totals $ 20,697,833 $ 143,258 (1) Same store primarily includes all properties acquired or completed that were stabilized prior to January 1, 2016, less properties subsequently sold, which represented 70,285 apartment (2) Non-same store primarily includes properties acquired after January 1, 2016, plus any properties in lease-up and not stabilized as of January 1, (3) Other includes development, other corporate operations and capital expenditures for properties

Business - Additional Informati

Business - Additional Information (Details)	Sep. 30, 2017StatePropertyApartmentUnit
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Number of States in which Entity Operates | State	10
Properties | Property	305
Apartment Units | ApartmentUnit	78,302
ERPOP [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	96.40%

Business - Ownership Breakdown

Business - Ownership Breakdown (Details)	Sep. 30, 2017PropertyApartmentUnit
Property/Unit schedule
Properties | Property	305
Apartment Units | ApartmentUnit	78,302
Wholly Owned Properties
Property/Unit schedule
Properties | Property	283
Apartment Units | ApartmentUnit	73,289
Master-Leased Properties – Consolidated
Property/Unit schedule
Properties | Property	3
Apartment Units | ApartmentUnit	853
Partially Owned Properties – Consolidated
Property/Unit schedule
Properties | Property	17
Apartment Units | ApartmentUnit	3,215
Partially Owned Properties – Unconsolidated
Property/Unit schedule
Properties | Property	2
Apartment Units | ApartmentUnit	945

Summary of Significant Accoun40

Summary of Significant Accounting Policies - Additional Information (Details)	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2017USD ($)	Sep. 30, 2017USD ($)PropertyApartmentUnit	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)PropertyApartmentUnit	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Provision for income tax		$ 228,000	$ 426,000	$ 710,000	$ 1,189,000
Properties | Property		305		305
Apartment Units | ApartmentUnit		78,302		78,302
Partially Owned Properties		$ 6,175,000		$ 6,175,000		$ 10,609,000
Partially Owned Properties – Consolidated
Properties | Property		17		17
Apartment Units | ApartmentUnit		3,215		3,215
Limited Life Partnership Properties [Member]
Properties | Property		4		4
Partially Owned Properties		$ 7,300,000		$ 7,300,000
Noncontrolling Interests Settlement Value		$ 65,800,000		65,800,000
Adjustments for New Accounting Principle, Early Adoption
Gain (loss) on equity transaction	$ 0
Federal [Member]
Provision for income tax				$ 0

Equity, Capital and Other Int41

Equity, Capital and Other Interests - Changes in Issued and Outstanding Common Shares and Units (Details)	9 Months Ended
	Sep. 30, 2017shares
Equity Capital And Other Interests [Abstract]
Common Stock, Shares, Outstanding	365,870,924
Common Shares Issued:
Conversion of OP Units	1,107,735
Exercise of share options	343,527
Employee Share Purchase Plan (ESPP)	54,843
Restricted share grants, net	85,451
Common Stock, Shares, Outstanding	367,462,480
Units
Total Units Outstanding	14,626,075
Restricted unit grants, net	291,647
Conversion of OP Units to Common Shares	(1,107,735)
Total Units Outstanding	13,809,987
Common Shares And Units Outstanding	381,272,467
Units Ownership Interest in Operating Partnership	3.60%

Equity, Capital and Other Int42

Equity, Capital and Other Interests - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Class Of Stock [Line Items]
Redeemable Noncontrolling Interests – Operating Partnership	$ 380,541	$ 442,092
Preferred Stock, Shares Authorized	100,000,000	100,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
ERPOP [Member]
Class Of Stock [Line Items]
Redeemable Limited Partners	$ 380,541	$ 442,092

Equity, Capital and Other Int43

Equity, Capital and Other Interests - Changes in Redemption Value of Redeemable Noncontrolling Interests - Operating Partnership (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Equity Capital And Other Interests [Abstract]
Redeemable Noncontrolling Interests – Operating Partnership	$ 442,092
Change in market value of Redeemable Noncontrolling Interests – Operating Partnership	(29,551)
Change in carrying value of Redeemable Noncontrolling Interests - Operating Partnership	(32,000)
Redeemable Noncontrolling Interests – Operating Partnership	$ 380,541

Equity, Capital and Other Int44

Equity, Capital and Other Interests - Issued and Outstanding Preferred Shares and Preference Units (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Class Of Stock [Line Items]
8.29% Series K Cumulative Redeemable Preferred; liquidation value $50 per share; 745,600 shares issued and outstanding at September 30, 2017 and December 31, 2016	$ 37,280	$ 37,280
ERPOP [Member]
Class Of Stock [Line Items]
8.29% Series K Cumulative Redeemable Preferred; liquidation value $50 per share; 745,600 shares issued and outstanding at September 30, 2017 and December 31, 2016	$ 37,280	37,280
Series K Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred Stocks Preference Units Call Date	Dec. 10, 2026
Annual Dividend Per Preferred Share Preference Unit	$ 4.145
8.29% Series K Cumulative Redeemable Preferred; liquidation value $50 per share; 745,600 shares issued and outstanding at September 30, 2017 and December 31, 2016	$ 37,280	37,280
Series K Preferred Stock [Member] | ERPOP [Member]
Class Of Stock [Line Items]
Preferred Stocks Preference Units Call Date	Dec. 10, 2026
Annual Dividend Per Preferred Share Preference Unit	$ 4.145
8.29% Series K Cumulative Redeemable Preferred; liquidation value $50 per share; 745,600 shares issued and outstanding at September 30, 2017 and December 31, 2016	$ 37,280	$ 37,280

Equity, Capital and Other Int45

Equity, Capital and Other Interests - Issued and Outstanding Preferred Shares and Preference Units (Parenthetical) (Details) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Class Of Stock [Line Items]
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	100,000,000	100,000,000
Series K Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred Stock Preference Units Issued	745,600	745,600
Preferred Stock Preference Units Outstanding	745,600	745,600
Preferred Stock Preference Units Redemption Price Per Share Unit	$ 50	$ 50
Preferred Stock Preference Units Dividend Rate Percentage	8.29%	8.29%
Series K Preferred Stock [Member] | ERPOP [Member]
Class Of Stock [Line Items]
Preferred Stock Preference Units Issued	745,600	745,600
Preferred Stock Preference Units Outstanding	745,600	745,600
Preferred Stock Preference Units Redemption Price Per Share Unit	$ 50	$ 50
Preferred Stock Preference Units Dividend Rate Percentage	8.29%	8.29%

Equity, Capital and Other Int46

Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding Units (Details)	9 Months Ended
	Sep. 30, 2017shares
General and Limited Partner Units
Exercise of share options	343,527
Employee Share Purchase Plan (ESPP)	54,843
Restricted share grants, net	85,451
Restricted unit grants, net	291,647
Common Shares And Units Outstanding	381,272,467
LIMITED PARTNERS
Total Units Outstanding	14,626,075
Restricted unit grants, net	291,647
Conversion of Limited Partner OP Units to EQR Common Shares	(1,107,735)
Total Units Outstanding	13,809,987
Units Ownership Interest in Operating Partnership	3.60%
ERPOP [Member]
General and Limited Partner Units
Common Shares And Units Outstanding	380,496,999
Exercise of share options	343,527
Employee Share Purchase Plan (ESPP)	54,843
Restricted share grants, net	85,451
Restricted unit grants, net	291,647
Common Shares And Units Outstanding	381,272,467
LIMITED PARTNERS
Total Units Outstanding	14,626,075
Restricted unit grants, net	291,647
Conversion of Limited Partner OP Units to EQR Common Shares	(1,107,735)
Total Units Outstanding	13,809,987
Units Ownership Interest in Operating Partnership	3.60%

Equity, Capital and Other Int47

Equity, Capital and Other Interests - Changes in Redemption Value of Redeemable Limited Partners Interest (Details) - ERPOP [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Redeemable Limited Partners	$ 442,092
Limited Partners Change In Redemption Value	(29,551)
Limited Partners Change In Carrying Value	(32,000)
Redeemable Limited Partners	$ 380,541

Equity, Capital and Other Int48

Equity, Capital and Other Interests - Other - Additional Information (Details)	9 Months Ended
	Sep. 30, 2017shares
Equity Capital And Other Interests [Abstract]
Additional Common Shares Authorized	13,000,000
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	13,000,000
Stock Repurchased and Retired During Period, Shares	0

Real Estate and Lease Intangi49

Real Estate and Lease Intangibles - Summary of Carrying Amounts of Investment in Real Estate (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Land	$ 5,985,004	$ 5,899,862
Depreciable property:
Buildings and improvements	17,601,348	16,913,430
Furniture, fixtures and equipment	1,500,963	1,346,300
In-Place lease intangibles	469,091	470,849
Projects under development:
Construction-in-progress	293,064	637,168
Land held for development:
Land	99,073	118,816
Construction-in-progress	293,064	637,168
Investment in real estate	25,948,543	25,386,425
Accumulated depreciation	(5,849,110)	(5,360,389)
Investment in real estate, net	20,099,433	20,026,036
Projects under development [Member]
Projects under development:
Land	61,047	115,876
Construction-in-progress	232,017	521,292
Land held for development:
Construction-in-progress	232,017	521,292
Land held for development [Member]
Projects under development:
Construction-in-progress	35,634	34,376
Land held for development:
Land	63,439	84,440
Construction-in-progress	$ 35,634	$ 34,376

Real Estate and Lease Intangi50

Real Estate and Lease Intangibles - Summary of Carrying Amounts of Above and Below Market Ground And Retail Lease Intangibles (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Other Assets [Member]
Lease intangible assets	$ 193,178	$ 179,511
Finite-Lived Intangible Assets, Accumulated Amortization	(21,305)	(17,972)
Lease intangible assets, net	171,873	161,539
Other Assets [Member] | Ground Lease [Member]
Finite-Lived Intangible Asset, Off-market Lease, Favorable, Gross	191,918	178,251
Other Assets [Member] | Retail Lease [Member]
Finite-Lived Intangible Asset, Off-market Lease, Favorable, Gross	1,260	1,260
Other Liabilities [Member]
Lease Intangible Liabilities	7,670	7,670
Finite Lived Intangible Liabilities Accumulated Amortization	(5,113)	(4,509)
Lease intangible liabilities, net	2,557	3,161
Other Liabilities [Member] | Ground Lease [Member]
Finite-Lived Intangible Liabilities, Off-market Lease, Unfavorable, Gross	2,400	2,400
Other Liabilities [Member] | Retail Lease [Member]
Finite-Lived Intangible Liabilities, Off-market Lease, Unfavorable, Gross	$ 5,270	$ 5,270

Real Estate and Lease Intangi51

Real Estate and Lease Intangibles - Summary of the Effect of the Amortization for Above and Below Market Ground and Retail Lease Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Total amortization of above/below market lease intangibles	$ (1,012)	$ (858)	$ (2,729)	$ (2,566)
Ground Lease [Member] | Property and Maintenance [Member]
Total amortization of above/below market lease intangibles	(1,092)	(1,080)	(3,253)	(3,241)
Retail Lease [Member] | Rental Income [Member]
Total amortization of above/below market lease intangibles	$ 80	$ 222	$ 524	$ 675

Real Estate and Lease Intangi52

Real Estate and Lease Intangibles - Summary of Aggregate Amortization for Above and Below Market Ground And Retail Lease Intangibles (Details) $ in Thousands	Sep. 30, 2017USD ($)
Finite-lived intangible assets, amortization expense, remainder of fiscal year 2017	$ (1,100)
Finite-lived intangible assets, amortization expense, year 2018	(4,392)
Finite-lived intangible assets, amortization expense, year 2019	(4,392)
Finite-lived intangible assets, amortization expense, year 2020	(4,392)
Finite-lived intangible assets, amortization expense, year 2021	(4,392)
Finite-lived intangible assets, amortization expense, year 2022	(4,436)
Ground Lease [Member]
Finite-lived intangible assets, amortization expense, remainder of fiscal year 2017	(1,116)
Finite-lived intangible assets, amortization expense, year 2018	(4,463)
Finite-lived intangible assets, amortization expense, year 2019	(4,463)
Finite-lived intangible assets, amortization expense, year 2020	(4,463)
Finite-lived intangible assets, amortization expense, year 2021	(4,463)
Finite-lived intangible assets, amortization expense, year 2022	(4,463)
Retail Lease [Member]
Finite lived intangible assets amortization income, reminder of fiscal year 2017	16
Finite-lived intangible assets; amortization income, year 2018	71
Finite-lived intangible assets; amortization income, year 2019	71
Finite-lived intangible assets; amortization income, year 2020	71
Finite-lived intangible assets; amortization income, year 2021	71
Finite-lived intangible assets; amortization income, year 2022	$ 27

Real Estate and Lease Intangi53

Real Estate and Lease Intangibles - Real Estate Acquisitions and Dispositions (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)PropertyApartmentUnit
Properties acquired | Property	4
Property Units acquired | ApartmentUnit	947
Purchase Price	$ 468,050
Properties disposed | Property	4
Property Units disposed | ApartmentUnit	1,024
Sales Price	$ 353,150
Rental Properties – Consolidated [Member]
Properties acquired | Property	4
Property Units acquired | ApartmentUnit	947
Purchase Price	$ 468,050
Properties disposed | Property	4
Property Units disposed | ApartmentUnit	1,024
Sales Price	$ 319,700
Land [Member]
Purchase Price	68,300
Sales Price	$ 33,450

Real Estate and Lease Intangi54

Real Estate and Lease Intangibles - Real Estate Acquisitions and Dispositions (Parenthetical) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Purchase Price	$ 468,050
Ground Lease [Member] | Other Assets [Member]
Acquired ground lease intangibles – below market	191,918	$ 178,251
Land [Member]
Purchase Price	68,300
Depreciable Property [Member]
Purchase Price	386,200
Rental Properties – Consolidated [Member]
Purchase Price	$ 468,050
Rental Properties – Consolidated [Member] | Ground Lease [Member]
Lease expiration year	2,113
Rental Properties – Consolidated [Member] | Ground Lease [Member] | Other Assets [Member]
Acquired ground lease intangibles – below market	$ 13,700

Real Estate and Lease Intangi55

Real Estate and Lease Intangibles - Acquisitions and Dispositions - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Real Estate [Abstract]
Net gain on sales of real estate properties	$ 17,328	$ 90,036	$ 141,761	$ 3,870,871
Net gain (loss) on sales of land parcels		$ 4,037	$ 19,170	$ 15,759

Commitments to Acquire_Dispos56

Commitments to Acquire/Dispose of Real Estate - Separate Agreement to Dispose of (Details) - Subsequent Event [Member] $ in Thousands	Oct. 27, 2017USD ($)
Property/Unit schedule
Sales Price	$ 2,700
Land [Member]
Property/Unit schedule
Sales Price	$ 2,700

Commitments to Acquire_Dispos57

Commitments to Acquire/Dispose of Real Estate - Separate Agreement to Dispose of (Parenthetical) (Details)	Oct. 27, 2017Land
Subsequent Event [Member] | Land [Member]
Property/Unit schedule
Land Parcels	1

Investments in Partially Owne58

Investments in Partially Owned Entities - Partially Owned Property Balance Sheet Schedule (Details) $ in Thousands	Sep. 30, 2017USD ($)PropertyApartmentUnit	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Dec. 31, 2015USD ($)
Partially Owned Property Balance Sheet Schedule
Total properties | Property	305
Total apartment units | ApartmentUnit	78,302
ASSETS
Investment in real estate	$ 25,948,543	$ 25,386,425
Accumulated depreciation	(5,849,110)	(5,360,389)
Investment in real estate, net	20,099,433	20,026,036
Cash and cash equivalents	46,565	77,207	$ 517,586	$ 42,276
Investments in unconsolidated entities	59,029	60,141
Deposits – restricted	36,639	76,946
Other assets	445,195	398,883
Total assets	20,697,833	20,704,148
LIABILITIES AND EQUITY
Mortgage notes payable, net	3,619,180	4,119,181
Accounts payable and accrued expenses	167,984	147,482
Accrued interest payable	72,811	60,946
Other liabilities	332,650	350,466
Security deposits	65,230	62,624
Total liabilities	9,823,516	9,801,072
Partially Owned Properties	6,175	10,609
Total equity	10,493,776	10,460,984
Total liabilities and equity/capital	$ 20,697,833	$ 20,704,148
Unconsolidated Non-VIE
Partially Owned Property Balance Sheet Schedule
Total properties | Property	2
Total apartment units | ApartmentUnit	945
ASSETS
Investment in real estate	$ 236,630
Accumulated depreciation	(40,840)
Investment in real estate, net	195,790
Cash and cash equivalents	7,194
Investments in unconsolidated entities	0
Deposits – restricted	258
Other assets	450
Total assets	203,692
LIABILITIES AND EQUITY
Mortgage notes payable, net	145,424
Accounts payable and accrued expenses	2,644
Accrued interest payable	691
Other liabilities	308
Security deposits	488
Total liabilities	149,555
Partially Owned Properties	54,336
Company equity/General and Limited Partners' Capital	(199)
Total equity	54,137
Total liabilities and equity/capital	$ 203,692
Consolidated VIE
Partially Owned Property Balance Sheet Schedule
Total properties | Property	17
Total apartment units | ApartmentUnit	3,215
ASSETS
Investment in real estate	$ 648,839
Accumulated depreciation	(226,607)
Investment in real estate, net	422,232
Cash and cash equivalents	22,914
Investments in unconsolidated entities	45,035
Deposits – restricted	385
Other assets	26,246
Total assets	516,812
LIABILITIES AND EQUITY
Mortgage notes payable, net	302,037
Accounts payable and accrued expenses	2,975
Accrued interest payable	1,024
Other liabilities	453
Security deposits	2,037
Total liabilities	308,526
Partially Owned Properties	6,175
Company equity/General and Limited Partners' Capital	202,111
Total equity	208,286
Total liabilities and equity/capital	$ 516,812
Unconsolidated VIE
Partially Owned Property Balance Sheet Schedule
Total properties | Property	0
Total apartment units | ApartmentUnit	0
ASSETS
Investment in real estate	$ 172,995
Accumulated depreciation	(48,670)
Investment in real estate, net	124,325
Cash and cash equivalents	139
Investments in unconsolidated entities	0
Deposits – restricted	0
Other assets	105
Total assets	124,569
LIABILITIES AND EQUITY
Mortgage notes payable, net	0
Accounts payable and accrued expenses	150
Accrued interest payable	0
Other liabilities	27
Security deposits	0
Total liabilities	177
Partially Owned Properties	84,682
Company equity/General and Limited Partners' Capital	39,710
Total equity	124,392
Total liabilities and equity/capital	$ 124,569
Partially Owned Properties – Unconsolidated
Partially Owned Property Balance Sheet Schedule
Total properties | Property	2
Total apartment units | ApartmentUnit	945
ASSETS
Investment in real estate	$ 409,625
Accumulated depreciation	(89,510)
Investment in real estate, net	320,115
Cash and cash equivalents	7,333
Investments in unconsolidated entities	0
Deposits – restricted	258
Other assets	555
Total assets	328,261
LIABILITIES AND EQUITY
Mortgage notes payable, net	145,424
Accounts payable and accrued expenses	2,794
Accrued interest payable	691
Other liabilities	335
Security deposits	488
Total liabilities	149,732
Partially Owned Properties	139,018
Company equity/General and Limited Partners' Capital	39,511
Total equity	178,529
Total liabilities and equity/capital	$ 328,261

Investments in Partially Owne59

Investments in Partially Owned Entities - Partially Owned Property Income Statement Schedule (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Partially Owned Property Income Statement Schedule
Operating revenue	$ 624,122	$ 606,074	$ 1,840,702	$ 1,820,311
Property management	20,861	19,517	64,702	64,003
General and administrative	12,567	12,395	40,366	47,408
Depreciation	184,100	179,230	542,964	528,242
Operating income	217,786	209,373	632,707	632,016
Interest and other income	3,945	5,509	5,708	65,092
Interest:
Expense incurred, net	(91,145)	(86,352)	(288,579)	(386,316)
Amortization of deferred financing costs	(2,064)	(2,261)	(6,447)	(10,000)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations	127,494	115,849	340,229	286,312
Income and other tax (expense) benefit	(228)	(426)	(710)	(1,189)
(Loss) from investments in unconsolidated entities	(398)	7,750	(2,153)	5,846
Net income	$ 144,196	$ 217,492	498,297	$ 4,177,723
Unconsolidated Non-VIE
Partially Owned Property Income Statement Schedule
Operating revenue			20,050
Operating expenses			6,746
Net operating income			13,304
Property management			584
General and administrative			1
Depreciation			7,960
Operating income			4,759
Interest and other income			0
Interest:
Expense incurred, net			(6,217)
Amortization of deferred financing costs			(1)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations			(1,459)
Income and other tax (expense) benefit			(13)
(Loss) from investments in unconsolidated entities			0
Net income			(1,472)
Consolidated VIE
Partially Owned Property Income Statement Schedule
Operating revenue			69,917
Operating expenses			17,056
Net operating income			52,861
Property management			2,463
General and administrative			239
Depreciation			15,569
Operating income			34,590
Interest and other income			45
Interest:
Expense incurred, net			(9,977)
Amortization of deferred financing costs			(203)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations			24,455
Income and other tax (expense) benefit			(34)
(Loss) from investments in unconsolidated entities			(1,155)
Net income			23,266
Unconsolidated VIE
Partially Owned Property Income Statement Schedule
Operating revenue			3,805
Operating expenses			1,573
Net operating income			2,232
Property management			56
General and administrative			127
Depreciation			4,126
Operating income			(2,077)
Interest and other income			0
Interest:
Expense incurred, net			0
Amortization of deferred financing costs			0
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations			(2,077)
Income and other tax (expense) benefit			0
(Loss) from investments in unconsolidated entities			0
Net income			(2,077)
Partially Owned Properties – Unconsolidated
Partially Owned Property Income Statement Schedule
Operating revenue			23,855
Operating expenses			8,319
Net operating income			15,536
Property management			640
General and administrative			128
Depreciation			12,086
Operating income			2,682
Interest and other income			0
Interest:
Expense incurred, net			(6,217)
Amortization of deferred financing costs			(1)
Income before income and other taxes, (loss) income from investments in unconsolidated entities, net gain on sales of real estate properties and land parcels and discontinued operations			(3,536)
Income and other tax (expense) benefit			(13)
(Loss) from investments in unconsolidated entities			0
Net income			$ (3,549)

Investments in Partially Owne60

Investments in Partially Owned Entities - Partially Owned Property Income Statement Schedule (Parenthetical) (Details) - Unconsolidated Non-VIE $ in Millions	Sep. 30, 2017USD ($)
Legacy JV [Member]
Liquidation Value Preferred Interests	$ 37.4
PARTIALLY OWNED PROPERTIES
Joint venture ownership percentage owned by company	60.00%
Residual JV [Member]
PARTIALLY OWNED PROPERTIES
Joint venture ownership percentage owned by company	60.00%

Investments in Partially Owne61

Investments in Partially Owned Entities - Operating Properties - Additional Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)PropertyApartmentUnit	Dec. 31, 2016USD ($)
Variable Interest Entity [Line Items]
Properties | Property	305
Apartment Units | ApartmentUnit	78,302
Investments in unconsolidated entities	$ 59,029	$ 60,141
Secured Debt	$ 3,619,180	$ 4,119,181
Nexus Sawgrass [Member]
Variable Interest Entity [Line Items]
Apartment Units | ApartmentUnit	501
Investments in unconsolidated entities	$ 4,400
Equity Method Investment, Ownership Percentage	20.00%
Secured Debt	$ 48,600
Debt Instrument, Interest Rate, Stated Percentage	5.60%
Debt Instrument, Maturity Date	Jan. 1, 2021
Consolidated VIE
Variable Interest Entity [Line Items]
Properties | Property	17
Apartment Units | ApartmentUnit	3,215
Investments in unconsolidated entities	$ 45,035
Secured Debt	$ 302,037
Unconsolidated VIE
Variable Interest Entity [Line Items]
Properties | Property	0
Apartment Units | ApartmentUnit	0
Investments in unconsolidated entities	$ 0
Secured Debt	$ 0
Operating Property [Member] | Consolidated VIE
Variable Interest Entity [Line Items]
Properties | Property	16
Apartment Units | ApartmentUnit	2,783
Wisconsin Place [Member] | Consolidated VIE
Variable Interest Entity [Line Items]
Apartment Units | ApartmentUnit	432
Joint venture ownership percentage owned by company	75.00%
Basis of joint venture	$ 167,000
Wisconsin Place [Member] | Unconsolidated VIE
Variable Interest Entity [Line Items]
Investments in unconsolidated entities	$ 45,000
Domain [Member]
Variable Interest Entity [Line Items]
Apartment Units | ApartmentUnit	444
Investments in unconsolidated entities	$ 8,400
Equity Method Investment, Ownership Percentage	20.00%
Secured Debt	$ 96,800
Debt Instrument, Interest Rate, Stated Percentage	5.75%
Debt Instrument, Maturity Date	Jan. 1, 2022

Investments in Partially Owne62

Investments in Partially Owned Entities - Other - Additional Information (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
Investments in unconsolidated entities	$ 59,029,000	$ 60,141,000
Unconsolidated Non-VIE
Variable Interest Entity [Line Items]
Investments in unconsolidated entities	0
Unconsolidated Non-VIE | Residual JV [Member]
Variable Interest Entity [Line Items]
Investments in unconsolidated entities	$ 400,000
Joint venture ownership percentage owned by company	60.00%
Joint Venture Partner Ownership Percentage	40.00%
Unconsolidated Non-VIE | Legacy JV [Member]
Variable Interest Entity [Line Items]
Joint venture ownership percentage owned by company	60.00%
Joint Venture Partner Ownership Percentage	40.00%
Liquidation Value Preferred Interests	$ 37,400,000
Private Equity Fund | Capital Commitment
Variable Interest Entity [Line Items]
Investments in unconsolidated entities	1,600,000
Private Equity Fund | Maximum [Member]
Variable Interest Entity [Line Items]
Investments in unconsolidated entities	$ 5,000,000

Deposits Restricted and Escrow

Deposits Restricted and Escrow Deposits Mortgage - Restricted Deposits (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Cash And Cash Equivalents [Abstract]
Tax-deferred (1031) exchange proceeds		$ 38,847
Restricted deposits on real estate investments	$ 61	733
Resident security and utility deposits	35,667	37,007
Other	911	359
Totals	$ 36,639	$ 76,946

Deposits Restricted and Escro64

Deposits Restricted and Escrow Deposits Mortgage - Escrow Deposits for Mortgages (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Cash And Cash Equivalents [Abstract]
Real estate taxes and insurance	$ 556	$ 2,003
Replacement reserves	7,969	3,428
Mortgage principal reserves/sinking funds	1,595	58,652
Other	852	852
Totals	$ 10,972	$ 64,935

Deposits - Restricted and Esc65

Deposits - Restricted and Escrow Deposits - Mortgage - Additional Information (Details) $ in Millions	9 Months Ended
	Sep. 30, 2017USD ($)
Cash And Cash Equivalents [Abstract]
Proceeds from return of various mortgage principal reserves/sinking funds	$ 60.5

Debt - Mortgage Notes Payable -

Debt - Mortgage Notes Payable - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Mortgage notes payable	$ 3,619,180	$ 4,119,181
Conventional Mortgage Loan [Member]
Debt Instrument [Line Items]
Repayments of Long-term Debt	193,400
Prepayment penalty charges	$ 1,500
Debt instrument maturity year, start	2,017
Debt instrument maturity year, end	2,048
Mortgages [Member]
Debt Instrument [Line Items]
Repayments of Long-term Debt	$ 8,800
Write off of Deferred Debt Issuance Cost	300
Write off unamortized (premium) discount	$ (700)
Debt Instrument, Maturity Date	May 28, 2061
Weighted Average Mortgage Debt Interest Rate	4.33%
Mortgages [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	0.10%
Mortgages [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.90%
Credit enhanced debt [Member]
Debt Instrument [Line Items]
Mortgage notes payable	$ 598,700
Fannie Mae Pool 3 [Member] | Mortgages [Member]
Debt Instrument [Line Items]
Repayments of Long-term Debt	$ 300,000
Debt Instrument, Interest Rate, Stated Percentage	5.987%
Debt instrument, maturity year	2,019
Prepayment penalty charges	$ 10,800

Debt - Notes - Additional Infor

Debt - Notes - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Unsecured notes	$ 5,143,248,000		$ 4,848,079,000
Repayments of Notes Payable	$ 394,077,000	$ 1,500,000,000
Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Aug. 1, 2047
Weighted Average Interest Rate	4.41%
Notes Payable, Other Payables [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.375%
Notes Payable, Other Payables [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.57%
5.75 % Notes [Member]
Debt Instrument [Line Items]
Repayments of Notes Payable	$ 394,100,000
Debt Instrument, Interest Rate, Stated Percentage	5.75%
3.25% Notes [Member]
Debt Instrument [Line Items]
Public Notes, Face Value	$ 400,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Proceeds from Debt, Net of Issuance Costs	$ 399,300,000
Debt Instrument, Interest Rate, Effective Percentage	3.32%
4.00% Notes [Member]
Debt Instrument [Line Items]
Public Notes, Face Value	$ 300,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.00%
Proceeds from Debt, Net of Issuance Costs	$ 293,200,000
Debt Instrument, Interest Rate, Effective Percentage	4.11%

Debt - Line of Credit and Comme

Debt - Line of Credit and Commercial Paper - Additional Information (Details) - USD ($)	Nov. 03, 2016	Sep. 30, 2017	Nov. 02, 2016	Feb. 02, 2015
Commercial Paper [Member]
Line of Credit Facility [Line Items]
Unsecured revolving credit facility				$ 500,000,000
Commercial Paper, net		$ 229,800,000
commercial paper principal outstanding		230,000,000
Unamortized Discount		$ 200,000
Weighted average interest rate commercial paper		1.37%
Commercial Paper Weighted average days outstanding		18 days
Unsecured Revolving Credit Facility
Line of Credit Facility [Line Items]
Unsecured revolving credit facility	$ 2,000,000,000		$ 2,500,000,000
Debt Instrument, Maturity Date		Jan. 10, 2022
Ability to increase LOC facility	$ 750,000,000
Debt instrument, basis spread on variable rate	0.825%
Percentage points of line of credit facility commitment fee		0.125%
Revolving Credit Facility
Line of Credit Facility [Line Items]
Remaining borrowing capacity		$ 1,760,000,000
Amount restricted/dedicated to support letters of credit		$ 11,100,000

Debt - Other - Additional Infor

Debt - Other - Additional Information (Details) $ in Millions	Sep. 30, 2017USD ($)
Debt Disclosure [Abstract]
Letters of credit outstanding	$ 9

Derivative and Other Fair Val70

Derivative and Other Fair Value Instruments - Summary of Carrying and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt, net	$ 9,270,572	$ 9,191,331
Carrying Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt, net	8,992,272	8,987,258
Mortgage Notes Payable, Net [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt, net	3,630,477	4,161,001
Mortgage Notes Payable, Net [Member] | Carrying Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt, net	3,619,180	4,119,181
Unsecured Debt [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt, net	5,640,095	5,030,330
Unsecured Debt [Member] | Carrying Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt, net	$ 5,373,092	$ 4,868,077

Derivative and Other Fair Val71

Derivative and Other Fair Value Instruments - Summary of Consolidated Derivative Instruments (Details)	9 Months Ended
	Sep. 30, 2017USD ($)
Fair Value Hedges [Member]
Derivative [Line Items]
Current Notional Balance	$ 450,000,000
Earliest Maturity Date	2,019
Latest Maturity Date	2,019
Fair Value Hedges [Member] | Lowest [Member]
Derivative [Line Items]
Interest Rate	2.375%
Fair Value Hedges [Member] | Highest [Member]
Derivative [Line Items]
Interest Rate	2.375%
Forward Starting Swaps [Member]
Derivative [Line Items]
Current Notional Balance	$ 250,000,000
Earliest Maturity Date	2,028
Latest Maturity Date	2,029
Forward Starting Swaps [Member] | Lowest [Member]
Derivative [Line Items]
Interest Rate	2.1478%
Forward Starting Swaps [Member] | Highest [Member]
Derivative [Line Items]
Interest Rate	2.2895%

Derivative and Other Fair Val72

Derivative and Other Fair Value Instruments - Summary of Consolidated Derivative Instruments (Parenthetical) (Details)	9 Months Ended
	Sep. 30, 2017USD ($)
Forward Starting Swaps [Member]
Derivative [Line Items]
Current Notional Balance	$ 250,000,000
Forward Starting Swaps Mandatory Counterparty Terminations in 2019 [Member]
Derivative [Line Items]
Current Notional Balance	200,000,000
Forward Starting Swaps Mandatory Counterparty Terminations in 2020 [Member]
Derivative [Line Items]
Current Notional Balance	50,000,000
2.375% Notes [Member]
Derivative [Line Items]
Proceeds from issuance of unsecured debt	$ 450,000,000
Debt instrument, interest rate, stated percentage	2.375%
Debt instrument, maturity date	Jul. 1, 2019
Debt instrument, basis spread on variable rate	0.61%
2.375% Notes [Member] | London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Debt instrument, description of variable rate basis	LIBOR plus 0.61%

Derivative and Other Fair Val73

Derivative and Other Fair Value Instruments - Summary of Fair Value Measurements for Each Major Category of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	$ 136,774	$ 124,420
Assets, Fair Value Disclosure	141,139	126,277
Other Liabilities, Fair Value Disclosure	136,774	124,420
Liabilities, Fair Value Disclosure	136,774	124,420
Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners	380,541	442,092
Fair Value Hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	444	1,857
Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	3,921
Fair Value, Inputs, Level 1 [Member]
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	136,774	124,420
Assets, Fair Value Disclosure	136,774	124,420
Other Liabilities, Fair Value Disclosure	136,774	124,420
Liabilities, Fair Value Disclosure	136,774	124,420
Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners	0	0
Fair Value, Inputs, Level 1 [Member] | Fair Value Hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Fair Value, Inputs, Level 1 [Member] | Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0
Fair Value, Inputs, Level 2 [Member]
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	0	0
Assets, Fair Value Disclosure	4,365	1,857
Other Liabilities, Fair Value Disclosure	0	0
Liabilities, Fair Value Disclosure	0	0
Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners	380,541	442,092
Fair Value, Inputs, Level 2 [Member] | Fair Value Hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	444	1,857
Fair Value, Inputs, Level 2 [Member] | Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	3,921
Fair Value, Inputs, Level 3 [Member]
Derivatives, Fair Value [Line Items]
Fair Value Of SERP Investments	0	0
Assets, Fair Value Disclosure	0	0
Other Liabilities, Fair Value Disclosure	0	0
Liabilities, Fair Value Disclosure	0	0
Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners	0	0
Fair Value, Inputs, Level 3 [Member] | Fair Value Hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0	$ 0
Fair Value, Inputs, Level 3 [Member] | Forward Starting Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 0

Derivative and Other Fair Val74

Derivative and Other Fair Value Instruments - Summary of Effect of Fair Value Hedges on the Accompanying Consolidated Statements of Operations and Comprehensive Income (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) Recognized in Income on Derivative	$ (1,413)	$ 4,563
Amount of Gain/(Loss) Recognized in Income on Hedged Item	1,413	(4,563)
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) Recognized in Income on Derivative	(1,413)	4,563
Amount of Gain/(Loss) Recognized in Income on Hedged Item	$ 1,413	$ (4,563)

Derivative and Other Fair Val75

Derivative and Other Fair Value Instruments - Summary of Effect of Cash Flow Hedges on the Accompanying Consolidated Statements of Operations and Comprehensive Income (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Effective Portion - Amount of Gain/(Loss) Recognized in OCI on Derivative	$ 5,216	$ (4,240)
Effective Portion - Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income	(14,019)	(37,262)
Ineffective Portion - Amount of Gain/ (Loss) Reclassified from Accumulated OCI into Income	0	0
Forward Starting Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Effective Portion - Amount of Gain/(Loss) Recognized in OCI on Derivative	5,216	(4,240)
Effective Portion - Amount of Gain/(Loss) Reclassified from Accumulated OCI into Income	(14,019)	(37,262)
Ineffective Portion - Amount of Gain/ (Loss) Reclassified from Accumulated OCI into Income	$ 0	$ 0

Derivative and Other Fair Val76

Derivative and Other Fair Value Instruments - Additional Information (Details)	1 Months Ended	9 Months Ended	12 Months Ended
	Aug. 31, 2017USD ($)DerivativeInstrument	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)
Derivative [Line Items]
Unrealized gain (loss) on interest rate cash flow hedges, pretax, accumulated other comprehensive income (loss)		$ 94,700,000	$ 113,900,000
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net		21,400,000
Proceeds from settlement of derivative instruments		$ 1,296,000
Forward Starting Swaps [Member]
Derivative [Line Items]
Proceeds from settlement of derivative instruments	$ 1,300,000
Forward Starting Swaps settled | DerivativeInstrument	4
Public Notes, Face Value	$ 400,000,000
Debt instrument, term	10 years

Earning Per Share and Earning77

Earning Per Share and Earnings Per Unit - Computation of Net Income per Share Basic and Net Income per Share Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ 144,196	$ 217,246	$ 498,297	$ 4,177,599
Allocation to Noncontrolling Interests – Operating Partnership, net	(5,166)	(8,344)	(17,931)	(160,437)
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Preferred distributions	(772)	(773)	(2,318)	(2,318)
Income from continuing operations available to Common Shares, net of Noncontrolling Interests	137,457	207,306	475,694	4,012,476
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	237	0	119
Net income available to Common Shares	137,457	207,543	475,694	4,012,595
Income From Continuing Operations Available To Common Shares	142,623	215,650	493,625	4,172,913
Discontinued operations, net	0	246	0	124
Net Income (Loss) Available to Common Stockholders, Diluted	$ 142,623	$ 215,896	$ 493,625	$ 4,173,037
Weighted average Common Shares outstanding	366,996	365,109	366,809	364,917
Dilutive Op Units	12,910	13,899	12,907	13,828
Long-term compensation shares/units	3,039	3,365	2,924	3,539
Weighted average Common Shares outstanding	382,945	382,373	382,640	382,284
Net income available to Common Shares	$ 0.37	$ 0.57	$ 1.30	$ 11
Net income available to Common Shares	0.37	0.56	1.29	10.92
Income from continuing operations available to Common Shares	0.37	0.57	1.30	11
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share	0	0	0	0
Earnings Per Share, Basic	0.37	0.57	1.30	11
Income from continuing operations available to Common Shares	0.37	0.56	1.29	10.92
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share	0	0	0	0
Earnings Per Share, Diluted	$ 0.37	$ 0.56	$ 1.29	$ 10.92

Earning Per Share and Earning78

Earning Per Share and Earnings Per Unit - Computation of Net Income per Unit Basic and Net Income per Unit Diluted for Operating Partnership (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income (loss) from continuing operations	$ 144,196	$ 217,246	$ 498,297	$ 4,177,599
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Discontinued operations, net	$ 0	$ 246	$ 0	$ 124
Weighted average Common Shares outstanding	382,945	382,373	382,640	382,284
Net income available to Common Shares	$ 0.37	$ 0.57	$ 1.30	$ 11
Net income available to Common Shares	0.37	0.56	1.29	10.92
Income from continuing operations available to Common Shares	0.37	0.57	1.30	11
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share	0	0	0	0
Earnings Per Share, Basic	0.37	0.57	1.30	11
Income from continuing operations available to Common Shares	0.37	0.56	1.29	10.92
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share	0	0	0	0
Earnings Per Share, Diluted	$ 0.37	$ 0.56	$ 1.29	$ 10.92
ERPOP [Member]
Income (loss) from continuing operations	$ 144,196	$ 217,246	$ 498,297	$ 4,177,599
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(801)	(823)	(2,354)	(2,368)
Allocation to Preference Units	(772)	(773)	(2,318)	(2,318)
Income Loss From Continuing Operations Available To Units	142,623	215,650	493,625	4,172,913
Discontinued operations, net	0	246	0	124
Numerator for net income per Unit – basic and diluted	$ 142,623	$ 215,896	$ 493,625	$ 4,173,037
Weighted Average Limited Partnership and General Partnership Units Outstanding, Basic	379,906	379,008	379,716	378,745
Dilutive Securities Options	3,039	3,365	2,924	3,539
Weighted average Common Shares outstanding	382,945	382,373	382,640	382,284
Net income available to Common Shares	$ 0.37	$ 0.57	$ 1.30	$ 11
Net income available to Common Shares	0.37	0.56	1.29	10.92
Income from continuing operations available to Common Shares	0.37	0.57	1.30	11
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share	0	0	0	0
Earnings Per Share, Basic	0.37	0.57	1.30	11
Income from continuing operations available to Common Shares	0.37	0.56	1.29	10.92
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share	0	0	0	0
Earnings Per Share, Diluted	$ 0.37	$ 0.56	$ 1.29	$ 10.92

Individually Significant Disp79

Individually Significant Dispositions - Additional Information (Details) $ in Thousands	Oct. 23, 2015USD ($)Property	Sep. 30, 2017USD ($)PropertyApartmentUnit	Sep. 30, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed Properties | Property		4
Disposed Units | ApartmentUnit		1,024
Proceeds From Sale Of Property | $		$ 353,150
Starwood Portfolio [Member] | Disposal Group, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed Properties | Property	72
Disposed Units	23,262
Proceeds From Sale Of Property | $	$ 5,365,000
Percentage of consolidated NOI			1.60%	15.70%

Individually Significant Disp80

Individually Significant Dispositions - Results of Operations Attributable to Starwood Transaction (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
REVENUES
Rental income	$ 623,951	$ 605,856	$ 1,840,170	$ 1,816,960
Total revenues	624,122	606,074	1,840,702	1,820,311
EXPENSES
Property and maintenance	104,721	104,216	306,645	309,688
Real estate taxes and insurance	84,087	81,343	253,318	238,954
Property management	20,861	19,517	64,702	64,003
General and administrative	12,567	12,395	40,366	47,408
Total expenses	406,336	396,701	1,207,995	1,188,295
Operating income	217,786	209,373	632,707	632,016
Interest and other income	3,945	5,509	5,708	65,092
Interest:
Expense incurred, net	(91,145)	(86,352)	(288,579)	(386,316)
Amortization of deferred financing costs	(2,064)	(2,261)	(6,447)	(10,000)
Income and other tax (expense) benefit	(228)	(426)	(710)	(1,189)
Net gain (loss) on sales of real estate properties	17,328	90,036	141,761	3,870,871
Income from operations attributable to Noncontrolling Interests – Operating Partnership	(5,166)	(8,353)	(17,931)	(160,442)
Net income attributable to controlling interests	$ 138,229	208,316	$ 478,012	4,014,913
Starwood Portfolio [Member] | Disposal Group, Not Discontinued Operations [Member]
REVENUES
Rental income		239		30,660
Total revenues		239		30,660
EXPENSES
Property and maintenance		(84)		7,839
Real estate taxes and insurance		1		2,933
Property management		0		2
General and administrative		4		19
Total expenses		(79)		10,793
Operating income		318		19,867
Interest and other income		10		21
Interest:
Expense incurred, net		(6)		(380)
Amortization of deferred financing costs		0		(707)
Income and other tax (expense) benefit		0		(1)
Net gain (loss) on sales of real estate properties		(103)		3,161,097
Income from operations attributable to controlling interests – Operating Partnership		219		3,179,897
Income from operations attributable to Noncontrolling Interests – Operating Partnership		(8)		(122,146)
Net income attributable to controlling interests		$ 211		$ 3,057,751

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) $ in Millions	9 Months Ended
	Sep. 30, 2017USD ($)PropertyApartmentUnit
Accrual for Environmental Loss Contingencies | $	$ 5.7
Number of properties with environmental reserves | Property	2
Loss Contingency Accrual | $	$ 0.9
Projects in various stages of development | Property	4
Units in various stages of development | ApartmentUnit	1,285
Consolidated Project Under Development Commitment Fund | $	$ 127.3
Various stages of development with estimated completion dates ranging through September 30, 2017	Sep. 30, 2019
Partially Owned Properties – Unconsolidated
Number Of Unconsolidated Projects | Property	2

Reportable Segments - Additiona

Reportable Segments - Additional Information (Details) - Customer	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Disclosure Of Entitys Reportable Segments [Abstract]
Number of customer contributed 10% or more of total revenue	0	0

Reportable Segments - Reconcili

Reportable Segments - Reconciliation of NOI from Rental Real Estate Specific to Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	$ 623,951	$ 605,856	$ 1,840,170	$ 1,816,960
Property and maintenance expense	(104,721)	(104,216)	(306,645)	(309,688)
Real estate taxes and insurance expense	(84,087)	(81,343)	(253,318)	(238,954)
Operating income	217,786	209,373	632,707	632,016
Same Store, Non-same Store and Other
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Rental income	623,951	605,856	1,840,170	1,816,960
Property and maintenance expense	(104,721)	(104,216)	(306,645)	(309,688)
Real estate taxes and insurance expense	(84,087)	(81,343)	(253,318)	(238,954)
Total operating expenses	(188,808)	(185,559)	(559,963)	(548,642)
Operating income	$ 435,143	$ 420,297	$ 1,280,207	$ 1,268,318

Reportable Segments - NOI for E

Reportable Segments - NOI for Each Segment from Our Rental Real Estate Specific to Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Rental income	$ 623,951	$ 605,856	$ 1,840,170	$ 1,816,960
Operating income	217,786	209,373	632,707	632,016
Total Assets	20,697,833		20,697,833		$ 20,704,148
Capital Expenditures			143,258
Same store
Segment Reporting Information [Line Items]
Rental income	587,142	574,594	1,685,303	1,647,988
Operating expenses	173,844	171,019	496,232	482,410
Operating income	413,298	403,575	1,189,071	1,165,578
Total Assets	16,731,045		16,731,045
Capital Expenditures			139,638
Non-same store/other
Segment Reporting Information [Line Items]
Rental income	36,809	31,262	154,867	168,972
Operating expenses	14,964	14,540	63,731	66,232
Operating income	21,845	16,722	91,136	102,740
Total Assets	3,966,788		3,966,788
Capital Expenditures			3,620
Same Store, Non-same Store and Other
Segment Reporting Information [Line Items]
Rental income	623,951	605,856	1,840,170	1,816,960
Operating expenses	188,808	185,559	559,963	548,642
Operating income	435,143	420,297	1,280,207	1,268,318
Other markets | Same store
Segment Reporting Information [Line Items]
Rental income	459	457	1,384	1,342
Operating expenses	158	136	499	428
Operating income	301	321	885	914
Total Assets	12,778		12,778
Capital Expenditures			83
Los Angeles | Same store
Segment Reporting Information [Line Items]
Rental income	102,566	98,542	296,345	285,463
Operating expenses	27,768	29,362	83,927	83,459
Operating income	74,798	69,180	212,418	202,004
Total Assets	2,620,672		2,620,672
Capital Expenditures			18,952
Orange County | Same store
Segment Reporting Information [Line Items]
Rental income	22,427	21,455	66,081	63,005
Operating expenses	5,500	5,362	16,355	15,529
Operating income	16,927	16,093	49,726	47,476
Total Assets	330,580		330,580
Capital Expenditures			6,671
San Diego | Same store
Segment Reporting Information [Line Items]
Rental income	22,432	21,516	66,052	63,171
Operating expenses	5,867	5,740	17,386	16,884
Operating income	16,565	15,776	48,666	46,287
Total Assets	425,241		425,241
Capital Expenditures			3,776
Subtotal - Southern California | Same store
Segment Reporting Information [Line Items]
Rental income	147,425	141,513	428,478	411,639
Operating expenses	39,135	40,464	117,668	115,872
Operating income	108,290	101,049	310,810	295,767
Total Assets	3,376,493		3,376,493
Capital Expenditures			29,399
Washington DC | Same store
Segment Reporting Information [Line Items]
Rental income	108,763	107,340	322,307	317,879
Operating expenses	33,459	32,817	98,043	95,187
Operating income	75,304	74,523	224,264	222,692
Total Assets	3,836,992		3,836,992
Capital Expenditures			26,308
New York | Same store
Segment Reporting Information [Line Items]
Rental income	125,351	124,709	345,656	345,434
Operating expenses	46,219	44,223	126,226	120,390
Operating income	79,132	80,486	219,430	225,044
Total Assets	4,181,890		4,181,890
Capital Expenditures			23,547
San Francisco | Same store
Segment Reporting Information [Line Items]
Rental income	98,805	97,259	283,654	277,666
Operating expenses	24,875	24,487	69,053	68,246
Operating income	73,930	72,772	214,601	209,420
Total Assets	2,480,069		2,480,069
Capital Expenditures			25,896
Boston | Same store
Segment Reporting Information [Line Items]
Rental income	57,071	56,368	170,545	168,118
Operating expenses	16,351	16,399	47,538	47,308
Operating income	40,720	39,969	123,007	120,810
Total Assets	1,670,467		1,670,467
Capital Expenditures			18,906
Seattle | Same store
Segment Reporting Information [Line Items]
Rental income	49,268	46,948	133,279	125,910
Operating expenses	13,647	12,493	37,205	34,979
Operating income	35,621	34,455	96,074	90,931
Total Assets	1,172,356		1,172,356
Capital Expenditures			15,499
Non-same store | Non-same store/other
Segment Reporting Information [Line Items]
Rental income	33,974	14,128	144,975	78,287
Operating expenses	10,371	6,120	53,367	29,173
Operating income	23,603	8,008	91,608	49,114
Total Assets	3,080,697		3,080,697
Capital Expenditures			3,206
Other | Non-same store/other
Segment Reporting Information [Line Items]
Rental income	2,835	17,134	9,892	90,685
Operating expenses	4,593	8,420	10,364	37,059
Operating income	(1,758)	$ 8,714	(472)	$ 53,626
Total Assets	$ 886,091		886,091
Capital Expenditures			$ 414

Reportable Segments - NOI for85

Reportable Segments - NOI for Each Segment from Our Rental Real Estate Specific to Continuing Operations (Parenthetical) (Details) - Property	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Disclosure Of Entitys Reportable Segments [Abstract]
Units in same store properties	72,049	72,049	70,285	70,285

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands	Nov. 01, 2017	Sep. 30, 2017	Sep. 30, 2016
Subsequent Event [Line Items]
Repayments of Notes Payable		$ 394,077	$ 1,500,000
Subsequent Event [Member] | 7.125% Notes [Member] | Unsecured Debt [Member]
Subsequent Event [Line Items]
Repayments of Notes Payable	$ 103,900
Debt Instrument, Interest Rate, Stated Percentage	7.125%