Federal Realty Investment Trust (FRT) 10-K 10 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 06, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Entity Registrant Name	FEDERAL REALTY INVESTMENT TRUST
Entity Central Index Key	34903
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Amendment Flag	FALSE
Trading Symbol	FRT
Entity Common Stock, Shares Outstanding		68,664,043
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$8.20

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
ASSETS
Operating (including $282,303 and $265,138 of consolidated variable interest entities, respectively)	$5,128,757	$4,618,258
Construction-in-progress	480,241	531,205
Real estate, at cost	5,608,998	5,149,463
Less accumulated depreciation and amortization (including $26,618 and $19,086 of consolidated variable interest entities, respectively)	-1,467,050	-1,350,471
Net real estate	4,141,948	3,798,992
Cash and cash equivalents	47,951	88,927
Accounts and notes receivable, net	93,291	84,838
Mortgage notes receivable, net	50,988	55,155
Investment in real estate partnerships	37,457	32,264
Prepaid expenses and other assets	160,167	145,062
Debt issuance costs, net of accumulated amortization of $11,441 and $9,535, respectively	15,068	14,056
Total assets	4,546,870	4,219,294
Liabilities
Mortgages payable (including $187,632 and $202,782 of consolidated variable interest entities, respectively)	563,698	588,456
Capital lease obligations	71,647	71,671
Notes payable	290,519	300,822
Senior notes and debentures	1,483,813	1,360,913
Accounts payable and accrued expenses	145,685	156,270
Dividends payable	60,620	52,385
Security deposits payable	14,115	12,772
Other liabilities and deferred credits	105,164	100,283
Total liabilities	2,735,261	2,643,572
Commitments and contingencies (Note 9)
Redeemable noncontrolling interests	119,053	104,425
Shareholders’ equity
Preferred shares, authorized 15,000,000 shares, $.01 par: 5.417% Series 1 Cumulative Convertible Preferred Shares, (stated at liquidation preference $25 per share), 399,896 shares issued and outstanding	9,997	9,997
Common shares of beneficial interest, $.01 par, 100,000,000 shares authorized, 68,605,783 and 66,701,422 shares issued and outstanding, respectively	687	667
Additional paid-in capital	2,281,223	2,062,708
Accumulated dividends in excess of net income	-683,991	-623,795
Accumulated other comprehensive loss	-3,515	-1,417
Total shareholders’ equity of the Trust	1,604,401	1,448,160
Noncontrolling interests	88,155	23,137
Total shareholders’ equity	1,692,556	1,471,297
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$4,546,870	$4,219,294

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parentheticals) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Operating - consolidated variable interest entities	$282,303	$265,138
Accumulated depreciation and amortization of consolidated variable interest entities	26,618	19,086
Accumulated amortization of debt issuance costs	11,441	9,535
Mortgages payable - consolidated variable interest entities	$187,632	$202,782
Preferred shares, authorized	15,000,000	15,000,000
Preferred shares, par	$0.01	$0.01
Series 1 Cumulative Convertible Preferred interest rate	5.42%	5.42%
Preferred Shares, 5.417% Series 1 Cumulative Convertible liquidation preference	$25	$25
Preferred shares, shares issued	399,896	399,896
Preferred shares, shares outstanding	399,896	399,896
Common shares of beneficial interest, par	$0.01	$0.01
Common shares of beneficial interest, shares authorized	100,000,000	100,000,000
Common shares of beneficial interest, shares issued	68,605,783	66,701,422
Common shares of beneficial interest, shares outstanding	68,605,783	66,701,422

Consolidated_Statements_Of_Com

Consolidated Statements Of Comprehensive Income (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUE
Rental income	$666,322	$620,089	$580,114
Other property income	14,758	12,169	20,211
Mortgage interest income	5,010	5,155	5,466
Total revenue	686,090	637,413	605,791
EXPENSES
Rental expenses	135,417	118,695	112,616
Real estate taxes	76,506	71,759	66,454
General and administrative	32,316	31,970	31,158
Depreciation and amortization	170,814	160,828	141,701
Total operating expenses	415,053	383,252	351,929
OPERATING INCOME	271,037	254,161	253,862
Other interest income	94	433	689
Interest expense	-93,941	-104,977	-113,336
Early extinguishment of debt	-10,545	-13,304	0
Income from real estate partnerships	1,243	1,498	1,757
INCOME FROM CONTINUING OPERATIONS	167,888	137,811	142,972
DISCONTINUED OPERATIONS
Discontinued operations - income	0	942	1,400
Discontinued operations - gain on sale of real estate	0	23,861	0
Results from discontinued operations	0	24,803	1,400
Income before gain on sale of real estate	167,888	162,614	144,372
Gain on sale of real estate	4,401	4,994	11,860
Net income	172,289	167,608	156,232
Net income attributable to noncontrolling interests	-7,754	-4,927	-4,307
NET INCOME ATTRIBUTABLE TO THE TRUST	164,535	162,681	151,925
Dividends on preferred shares	-541	-541	-541
NET INCOME AVAILABLE FOR COMMON SHAREHOLDERS	163,994	162,140	151,384
EARNINGS PER COMMON SHARE, BASIC
Continuing operations	$2.35	$2.01	$2.15
Discontinued operations	$0	$0.38	$0.02
Gain on sale of real estate	$0.07	$0.08	$0.19
EARNINGS PER COMMON SHARE, BASIC	$2.42	$2.47	$2.36
Weighted average common shares outstanding, basic	67,322	65,331	63,881
EARNINGS PER COMMON SHARE, DILUTED
Continuing operations	$2.34	$2	$2.14
Discontinued operations	$0	$0.38	$0.02
Gain on sale of real estate	$0.07	$0.08	$0.19
EARNINGS PER COMMON SHARE, DILUTED	$2.41	$2.46	$2.35
Weighted average number of common shares, diluted	67,492	65,483	64,056
Comprehensive Income
Net income	172,289	167,608	156,232
Other comprehensive (loss) income - change in value of interest rate swaps	-2,098	10,971	-8,448
COMPREHENSIVE INCOME	170,191	178,579	147,784
Comprehensive income attributable to noncontrolling interests	-7,754	-4,927	-4,307
COMPREHENSIVE INCOME ATTRIBUTABLE TO THE TRUST	$162,437	$173,652	$143,477

Consolidated_Statement_Of_Shar

Consolidated Statement Of Shareholders' Equity (USD $)	Total	Preferred Shares	Common shares	Additional Paid-in Capital	Accumulated Dividends in Excess of Net Income	Accumulated Other Comprehensive Loss	Noncontrolling Interests
In Thousands, except Share data, unless otherwise specified
Beginning balance at Dec. 31, 2011	$1,240,604	$9,997	$636	$1,764,940	($555,541)	($3,940)	$24,512
Beginning balance (in shares) at Dec. 31, 2011		399,896	63,544,150
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income, excluding amount attributable to noncontrolling interests	153,640				151,925		1,715
Other comprehensive (loss) income - change in value of interest rate swaps	-8,448					-8,448
Dividends declared to common shareholders	-182,813				-182,813
Dividends declared to preferred shareholders	-541				-541
Distributions declared to noncontrolling interests	-2,232						-2,232
Common shares issued (in shares)			1,039,405
Common shares issued	106,219		10	106,209
Exercise of stock options (in shares)			97,430
Exercise of stock options	5,667		1	5,666
Shares issued under dividend reinvestment plan (in shares)	22,814		22,814
Shares issued under dividend reinvestment plan	2,248			2,248
Share-based compensation expense, net of shares withheld for employee taxes (in shares)			111,647
Share-based compensation expense, net of shares withheld for employee taxes	10,371		1	10,370
Conversion and redemption of OP units	-828			-439			-389
Contributions from noncontrolling interests	175						175
Adjustment to redeemable noncontrolling interests	-13,469			-13,469
Ending balance at Dec. 31, 2012	1,310,593	9,997	648	1,875,525	-586,970	-12,388	23,781
Ending balance (in shares) at Dec. 31, 2012		399,896	64,815,446
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income, excluding amount attributable to noncontrolling interests	164,721				162,681		2,040
Other comprehensive (loss) income - change in value of interest rate swaps	10,971					10,971
Dividends declared to common shareholders	-198,965				-198,965
Dividends declared to preferred shareholders	-541				-541
Distributions declared to noncontrolling interests	-1,887						-1,887
Common shares issued (in shares)			1,735,089
Common shares issued	185,182		18	185,164
Exercise of stock options (in shares)			16,554
Exercise of stock options	1,015		0	1,015
Shares issued under dividend reinvestment plan (in shares)	20,026		20,026
Shares issued under dividend reinvestment plan	2,130			2,130
Share-based compensation expense, net of shares withheld for employee taxes (in shares)			91,831
Share-based compensation expense, net of shares withheld for employee taxes	9,357		1	9,356
Conversion and redemption of OP units (in shares)			22,476
Conversion and redemption of OP units	-1,422			-625			-797
Adjustment to redeemable noncontrolling interests	-9,857			-9,857
Ending balance at Dec. 31, 2013	1,471,297	9,997	667	2,062,708	-623,795	-1,417	23,137
Ending balance (in shares) at Dec. 31, 2013		399,896	66,701,422
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income, excluding amount attributable to noncontrolling interests	168,837				164,535		4,302
Other comprehensive (loss) income - change in value of interest rate swaps	-2,098					-2,098
Dividends declared to common shareholders	-224,190				-224,190
Dividends declared to preferred shareholders	-541				-541
Distributions declared to noncontrolling interests	-4,620						-4,620
Common shares issued (in shares)			1,768,703
Common shares issued	213,580		18	213,562
Exercise of stock options (in shares)	29,218		29,218
Exercise of stock options	2,262		1	2,261
Shares issued under dividend reinvestment plan (in shares)	18,705		18,705
Shares issued under dividend reinvestment plan	2,168			2,168
Share-based compensation expense, net of shares withheld for employee taxes (in shares)			87,735
Share-based compensation expense, net of shares withheld for employee taxes	9,606		1	9,605
Conversion and redemption of OP units (in shares)			0
Conversion and redemption of OP units	-63			-49			-14
Contributions from noncontrolling interests	65,350						65,350
Adjustment to redeemable noncontrolling interests	-9,032			-9,032
Ending balance at Dec. 31, 2014	$1,692,556	$9,997	$687	$2,281,223	($683,991)	($3,515)	$88,155
Ending balance (in shares) at Dec. 31, 2014		399,896	68,605,783

Consolidated_Statement_Of_Shar1

Consolidated Statement Of Shareholders' Equity (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Stockholders' Equity [Abstract]
Amounts attributable to redeemable noncontrolling interest	$3,452	$2,887	$2,592

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
OPERATING ACTIVITIES
Net income	$172,289	$167,608	$156,232
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization, including discontinued operations	170,814	161,099	142,039
Gain on sale of real estate	-4,401	-28,855	-11,860
Early extinguishment of debt	10,545	13,304	0
Income from real estate partnerships	-1,243	-1,498	-1,757
Other, net	733	2,704	4,348
Changes in assets and liabilities, net of effects of acquisitions and dispositions:
(Increase) decrease in accounts receivable, net	-3,063	-6,321	7,332
(Increase) decrease in prepaid expenses and other assets	-4,222	69	-7,793
Increase in accounts payable and accrued expenses	4,253	5,325	3,259
Increase in security deposits and other liabilities	425	1,063	4,833
Net cash provided by operating activities	346,130	314,498	296,633
INVESTING ACTIVITIES
Acquisition of real estate	-9,154	-87,276	-80,865
Capital expenditures - development and redevelopment	-314,654	-243,073	-129,346
Capital expenditures - other	-46,304	-47,069	-51,325
Proceeds from sale of real estate	0	42,866	0
Proceeds from sale of real estate in real estate partnership	10,406	0	0
Investment in real estate partnership	-6,731	0	0
Distribution from real estate partnership in excess of earnings	565	790	1,116
Leasing costs	-35,286	-12,393	-14,233
Repayment of mortgage and other notes receivable, net	5,008	957	1,095
Net cash used in investing activities	-396,150	-345,198	-273,558
FINANCING ACTIVITIES
Net repayments under revolving credit facility, net of costs	0	-1,929	0
Issuance of senior notes, net of costs	244,579	564,389	244,807
Redemption and retirement of senior notes	-134,240	-293,360	-175,000
Issuance of mortgages, capital leases and notes payable, net of costs	0	860	5,399
Repayment of mortgages, capital leases and notes payable	-94,422	-173,735	-53,414
Issuance of common shares	216,155	186,548	112,270
Dividends paid to common and preferred shareholders	-215,216	-193,016	-178,020
Distributions to and redemptions of noncontrolling interests	-7,812	-7,118	-9,935
Net cash provided by (used in) financing activities	9,044	82,639	-53,893
(Decrease) Increase in cash and cash equivalents	-40,976	51,939	-30,818
Cash and cash equivalents at beginning of year	88,927	36,988	67,806
Cash and cash equivalents at end of year	$47,951	$88,927	$36,988

Business_And_Organization

Business And Organization	12 Months Ended
	Dec. 31, 2014
Nature Of Operations [Abstract]
BUSINESS AND ORGANIZATION	BUSINESS AND ORGANIZATION
	Federal Realty Investment Trust (the “Trust”) is an equity real estate investment trust (“REIT”) specializing in the ownership, management, and redevelopment of retail and mixed-use properties. Our properties are located primarily in densely populated and affluent communities in strategically selected metropolitan markets in the Mid-Atlantic and Northeast regions of the United States, as well as in California. As of December 31, 2014, we owned or had a majority interest in community and neighborhood shopping centers and mixed-use properties which are operated as 89 predominantly retail real estate projects.
	We operate in a manner intended to enable us to qualify as a REIT for federal income tax purposes. A REIT that distributes at least 90% of its taxable income to its shareholders each year and meets certain other conditions is not taxed on that portion of its taxable income which is distributed to its shareholders.

Summary_Of_Significant_Account

Summary Of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Principles of Consolidation
	Our consolidated financial statements include the accounts of the Trust, its corporate subsidiaries, and all entities in which the Trust has a controlling interest or has been determined to be the primary beneficiary of a variable interest entity (“VIE”). The equity interests of other investors are reflected as noncontrolling interests or redeemable noncontrolling interests. All significant intercompany transactions and balances are eliminated in consolidation. We account for our interests in joint ventures, which we do not control, using the equity method of accounting.
	Use of Estimates
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America, referred to as “GAAP,” requires management to make estimates and assumptions that in certain circumstances affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities, and revenues and expenses. These estimates are prepared using management’s best judgment, after considering past, current and expected events and economic conditions. Actual results could differ from these estimates.
	Revenue Recognition and Accounts Receivable
	Our leases with tenants are classified as operating leases. Substantially all such leases contain fixed escalations which occur at specified times during the term of the lease. Base rents are recognized on a straight-line basis from when the tenant controls the space through the term of the related lease, net of valuation adjustments, based on management’s assessment of credit, collection and other business risk. Percentage rents, which represent additional rents based upon the level of sales achieved by certain tenants, are recognized at the end of the lease year or earlier if we have determined the required sales level is achieved and the percentage rents are collectible. Real estate tax and other cost reimbursements are recognized on an accrual basis over the periods in which the related expenditures are incurred. For a tenant to terminate its lease agreement prior to the end of the agreed term, we may require that they pay a fee to cancel the lease agreement. Lease termination fees for which the tenant has relinquished control of the space are generally recognized on the termination date. When a lease is terminated early but the tenant continues to control the space under a modified lease agreement, the lease termination fee is generally recognized evenly over the remaining term of the modified lease agreement.
	We make estimates of the collectability of our accounts receivable related to minimum rents, straight-line rents, expense reimbursements and other revenue. Accounts receivable is carried net of this allowance for doubtful accounts. Our determination as to the collectability of accounts receivable and correspondingly, the adequacy of this allowance, is based primarily upon evaluations of individual receivables, current economic conditions, historical experience and other relevant factors. The allowance for doubtful accounts is increased or decreased through bad debt expense. Accounts receivable are written-off when they are deemed to be uncollectible and we are no longer actively pursuing collection. At December 31, 2014 and 2013, our allowance for doubtful accounts was $12.4 million and $12.7 million, respectively.
	In some cases, primarily relating to straight-line rents, the collection of accounts receivable extends beyond one year. Our experience relative to unbilled straight-line rents is that a portion of the amounts otherwise recognizable as revenue is never billed to or collected from tenants due to early lease terminations, lease modifications, bankruptcies and other factors. Accordingly, the extended collection period for straight-line rents along with our evaluation of tenant credit risk may result in the nonrecognition of a portion of straight-line rental income until the collection of such income is reasonably assured. If our evaluation of tenant credit risk changes indicating more straight-line revenue is reasonably collectible than previously estimated and realized, the additional straight-line rental income is recognized as revenue. If our evaluation of tenant credit risk changes indicating a portion of realized straight-line rental income is no longer collectible, a reserve and bad debt expense is recorded. At December 31, 2014 and 2013, accounts receivable include approximately $66.1 million and $60.6 million, respectively, related to straight-line rents.
	Real Estate
	Land, buildings and improvements are recorded at cost. Depreciation is computed using the straight-line method. Estimated useful lives range generally from 35 years to a maximum of 50 years on buildings and major improvements. Minor improvements, furniture and equipment are capitalized and depreciated over useful lives ranging from 2 to 20 years. Maintenance and repairs that do not improve or extend the useful lives of the related assets are charged to operations as incurred. Tenant improvements are capitalized and depreciated over the life of the related lease or their estimated useful life, whichever is shorter. If a tenant vacates its space prior to contractual termination of its lease, the undepreciated balance of any tenant improvements are written off if they are replaced or have no future value. In 2014, 2013 and 2012, real estate depreciation expense was $155.7 million, $147.7 million and $128.7 million, respectively, including amounts from discontinued operations and assets under capital lease obligations.
	Sales of real estate are recognized only when sufficient down payments have been obtained, possession and other attributes of ownership have been transferred to the buyer and we have no significant continuing involvement. The application of these criteria can be complex and requires us to make assumptions. We believe these criteria were met for all real estate sold during the periods presented.
	Our methodology of allocating the cost of acquisitions to assets acquired and liabilities assumed is based on estimated fair values, replacement cost and/or appraised values. When we acquire operating real estate properties, the purchase price is allocated to land, building, improvements, leasing costs, intangibles such as in-place leases, assumed debt, if any, and to current assets and liabilities acquired, if any. The value allocated to in-place leases is amortized over the related lease term and reflected as rental income in the consolidated statements of comprehensive income. We consider qualitative and quantitative factors in evaluating the likelihood of a tenant exercising a below market renewal option and include such renewal options in the calculation of in-place lease value when we consider these to be bargain renewal options. If the value of below market lease intangibles includes renewal option periods, we include such renewal periods in the amortization period utilized. If a tenant vacates its space prior to contractual termination of its lease, the unamortized balance of any in-place lease value is written off to rental income.
	Transaction costs related to the acquisition of a business, such as broker fees, transfer taxes, legal, accounting, valuation, and other professional and consulting fees, are expensed as incurred and included in “general and administrative expenses” in our consolidated statements of comprehensive income. The acquisition of an operating shopping center typically qualifies as a business. For asset acquisitions not meeting the definition of a business, transaction costs are capitalized as part of the acquisition cost.
	When applicable, as lessee, we classify our leases of land and building as operating or capital leases. We are required to use judgment and make estimates in determining the lease term, the estimated economic life of the property and the interest rate to be used in determining whether or not the lease meets the qualification of a capital lease and is recorded as an asset.
	We capitalize certain costs related to the development and redevelopment of real estate including pre-construction costs, real estate taxes, insurance, construction costs and salaries and related costs of personnel directly involved. Additionally, we capitalize interest costs related to development and redevelopment activities. Capitalization of these costs begin when the activities and related expenditures commence and cease when the project is substantially complete and ready for its intended use at which time the project is placed in service and depreciation commences. Additionally, we make estimates as to the probability of certain development and redevelopment projects being completed. If we determine the development or redevelopment is no longer probable of completion, we expense all capitalized costs which are not recoverable.
	We review for impairment on a property by property basis. Impairment is recognized on properties held for use when the expected undiscounted cash flows for a property are less than its carrying amount at which time the property is written-down to fair value. Properties held for sale are recorded at the lower of the carrying amount or the expected sales price less costs to sell. Effective January 1, 2014, we adopted ASU 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity,” as further discussed in "Recently Adopted Accounting Pronouncements."  Prior to January 1, 2014, the sale or disposal of a “component of an entity” was treated as discontinued operations. The operating properties sold by us prior to January 1, 2014 typically met the definition of a component of an entity and as such the revenues and expenses associated with sold properties were reclassified to discontinued operations for all periods presented.
	Cash and Cash Equivalents
	We define cash and cash equivalents as cash on hand, demand deposits with financial institutions and short term liquid investments with an initial maturity, when purchased, under three months. Cash balances in individual banks may exceed the federally insured limit by the Federal Deposit Insurance Corporation (the “FDIC”). At December 31, 2014, we had $47.7 million in excess of the FDIC insured limit.
	Prepaid Expenses and Other Assets
	Prepaid expenses and other assets consist primarily of lease costs, prepaid property taxes and acquired above market leases. Capitalized lease costs are direct costs incurred which were essential to originate a lease and would not have been incurred had the leasing transaction not taken place and include third party commissions and salaries and related costs of personnel directly related to time spent obtaining a lease. Capitalized lease costs are amortized over the life of the related lease. If a tenant vacates its space prior to the contractual termination of its lease, the unamortized balance of any previously capitalized lease costs are written off.
	Debt Issuance Costs
	Costs related to the issuance of debt instruments are capitalized and are amortized as interest expense over the estimated life of the related issue using the straight-line method which approximates the effective interest method. If a debt instrument is paid off prior to its original maturity date, the unamortized balance of debt issuance costs are written off to interest expense or, if significant, included in “early extinguishment of debt.”
	Derivative Instruments
	At times, we may use derivative instruments to manage exposure to variable interest rate risk. We generally enter into interest rate swaps to manage our exposure to variable interest rate risk and treasury locks to manage the risk of interest rates rising prior to the issuance of debt. We enter into derivative instruments that qualify as cash flow hedges and do not enter into derivative instruments for speculative purposes.
	The interest rate swaps associated with our cash flow hedges are recorded at fair value on a recurring basis. We assess effectiveness of our cash flow hedges both at inception and on an ongoing basis. The effective portion of changes in fair value of the interest rate swaps associated with our cash flow hedges is recorded in accumulated other comprehensive loss and is subsequently reclassified into interest expense as interest is incurred on the related variable rate debt; within the next twelve months, we expect to reclassify an estimated $3.8 million as an increase to interest expense. Our cash flow hedges become ineffective if critical terms of the hedging instrument and the debt instrument do not perfectly match such as notional amounts, settlement dates, reset dates, calculation period and LIBOR rate. In addition, we evaluate the default risk of the counterparty by monitoring the credit worthiness of the counterparty. When ineffectiveness exists, the ineffective portion of changes in fair value of the interest rate swaps associated with our cash flow hedges is recognized in earnings in the period affected. Hedge ineffectiveness did not impact earnings in 2014, 2013 or 2012, and we do not anticipate it will have a significant effect in the future.
	See Note 8 for additional disclosures relating to our two existing interest rate swap agreements.
	Mortgage Notes Receivable
	We have made certain mortgage loans that, because of their nature, qualify as loan receivables. At the time the loans were made, we did not intend for the arrangement to be anything other than a financing and did not contemplate a real estate investment. We evaluate each investment to determine whether the loan arrangement qualifies as a loan, joint venture or real estate investment and the appropriate accounting thereon. Such determination affects our balance sheet classification of these investments and the recognition of interest income derived therefrom. On some of the loans we receive additional interest, however, we never receive in excess of 50% of the residual profit in the project, and because the borrower has either a substantial investment in the project or has guaranteed all or a portion of our loan (or a combination thereof), the loans qualify for loan accounting. The amounts under these arrangements are presented as mortgage notes receivable at December 31, 2014 and 2013.
	Mortgage notes receivable are recorded at cost, net of any valuation adjustments. Interest income is accrued as earned. Mortgage notes receivable are considered past due based on the contractual terms of the note agreement. On a quarterly basis, we evaluate the collectability of each mortgage note receivable based on various factors which may include payment history, expected fair value of the collateral securing the loan, internal and external credit information and/or economic trends. A loan is considered impaired when, based upon current information and events, it is probable that we will be unable to collect all amounts due under the existing contractual terms. When a loan is considered impaired, the amount of the loss accrual is calculated by comparing the carrying amount of the mortgage note receivable to the present value of expected future cash flows. Since all of our loans are collateralized by either a first or second mortgage, the loans have risk characteristics similar to the risks in owning commercial real estate.
	Share Based Compensation
	We grant share based compensation awards to employees and trustees typically in the form of restricted common shares, commons shares, and options. We measure stock based compensation expense based on the grant date fair value of the award and recognize the expense ratably over the requisite service period, which is typically the vesting period. See Note 15 for further discussion regarding our share based compensation plans and policies.
	Variable Interest Entities
	Certain entities that do not have sufficient equity at risk for the entity to finance its activities without additional subordinated financial support from other parties or in which equity investors do not have the characteristics of a controlling financial interest qualify as VIEs. VIEs are required to be consolidated by their primary beneficiary. The primary beneficiary of a VIE has both the power to direct the activities that most significantly impact economic performance of the VIE and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE.
	We have evaluated our investments in certain joint ventures including our real estate partnership with affiliates of a discretionary fund created and advised by ING Clarion Partners and determined that these joint ventures do not meet the requirements of a variable interest entity and, therefore, consolidation of these ventures is not required. These investments are accounted for using the equity method. We have also evaluated our mortgage loans receivable and determined that entities obligated under the mortgage loans are not VIEs for all periods presented. Our investment balances from our real estate partnership and mortgage notes receivable are presented separately in our consolidated balance sheets.
	On October 16, 2006, we acquired the leasehold interest in Melville Mall under a 20 year master lease. Additionally, we loaned the owner of Melville Mall $34.2 million secured by a second mortgage on the property. On June 3, 2014, we repaid the third party mortgage loan as further discussed in Note 7, and effectively became the first mortgage lender on the property. We have an option to purchase the shopping center on or after October 16, 2021 for a price of $5.0 million plus the assumption/repayment of the first and second mortgages. If we fail to exercise our purchase option, the owner of Melville Mall has a put option which would require us to purchase Melville Mall in 2023 for $5.0 million and the assumption of the owner’s mortgage debt. We have determined that this property is held in a variable interest entity for which we are the primary beneficiary. Accordingly, beginning October 16, 2006, we consolidated this property and its operations. As of December 31, 2013, $20.7 million is included in mortgages payable (net of unamortized discount) for the mortgage loan secured by Melville Mall, however, the loan was not our legal obligation. At December 31, 2014 and 2013, net real estate assets related to Melville Mall included in our consolidated balance sheets are approximately $61.9 million and $62.6 million, respectively.
	In conjunction with the acquisition of Darien Shopping Center, we entered into a Reverse Section 1031 like-kind exchange agreement with a third party intermediary. The exchange agreement was for a maximum of 180 days and allowed us, for tax purposes, to defer gains on sale of other properties sold within this period. From April 3, 2013 to September 10, 2013, the third party intermediary was the legal owner of the property, although we controlled the activities that most significantly impacted the property, retained all of the economic benefits and risks associated with the property, and were the primary beneficiary. Accordingly, effective April 3, 2013, we consolidated Darien Shopping Center and its operations even during the period it was held by a third party intermediary.
	We determined the joint venture that owns Plaza El Segundo is a variable interest entity for which we are the primary beneficiary.  We are the managing member and own 48.2% of the entity.  We control the significant operating decisions, consequently having the power to direct the activities that most significantly impact economic performance of the VIE, and have the obligation to absorb the majority of the losses and receive the majority of the benefits.  Therefore, the entity is consolidated in our financial statements as of December 30, 2011.  As of December 31, 2014 and 2013, net real estate assets related to Plaza El Segundo included in our consolidated balance sheets are approximately $178.1 million and $183.4 million, respectively, and mortgages payable (net of unamortized premium) of $180.3 million and $182.1 million, respectively.  Plaza El Segundo's creditors do not have recourse to our general credit.  Our maximum exposure to loss is approximately $19.5 million.
	As further discussed in Note 3, we have entered into an agreement to acquire the interest of one of the noncontrolling interest holders in The Grove at Shrewsbury in 2015. The entity that holds this interest is a variable interest entity for which we are the primary beneficiary. As of December 31, 2014, net real estate assets related to this entity's interest in The Grove at Shrewsbury included in our consolidated balance sheet are approximately $15.7 million and a mortgage payable (net of unamortized premium) of $7.4 million.
	Redeemable Noncontrolling Interests
	We have certain noncontrolling interests that are redeemable for cash upon the occurrence of an event that is not solely in our control and therefore are classified outside of permanent equity. We adjust the carrying amounts of these noncontrolling interests that are currently redeemable to redemption value at the balance sheet date. Adjustments to the carrying amount to reflect changes in redemption value are recorded as adjustments to additional paid-in capital in shareholders' equity. These amounts are classified within the mezzanine section of the consolidated balance sheets.
	The following table provides a rollforward of the redeemable noncontrolling interests:
		Year Ended
		December 31,
		2014			2013
		(In thousands)
	Beginning balance	$	104,425		$	94,420
	Net income	3,452			2,887
	Distributions & Redemptions	(3,714		)	(3,822		)
	Contributions	5,858			1,083
	Adjustment to redeemable noncontrolling interests	9,032			9,857
	Ending balance	$	119,053		$	104,425
	Income Taxes
	We operate in a manner intended to enable us to qualify as a REIT for federal income tax purposes. A REIT that distributes at least 90% of its taxable income to its shareholders each year and meets certain other conditions is not taxed on that portion of its taxable income which is distributed to its shareholders. Therefore, federal income taxes on our taxable income have been and are generally expected to be immaterial. We are obligated to pay state taxes, generally consisting of franchise or gross receipts taxes in certain states. Such state taxes also have not been material.
	We have elected to treat certain of our subsidiaries as taxable REIT subsidiaries, which we refer to as a TRS. In general, a TRS may engage in any real estate business and certain non-real estate businesses, subject to certain limitations under the Internal Revenue Code of 1986, as amended (the “Code”). A TRS is subject to federal and state income taxes. Our TRS activities have not been material.
	With few exceptions, we are no longer subject to U.S. federal, state, and local tax examinations by tax authorities for years before 2010. As of December 31, 2014 and 2013, we had no material unrecognized tax benefits. While we currently have no material unrecognized tax benefits, as a policy, we recognize penalties and interest accrued related to unrecognized tax benefits as income tax expense.
	Segment Information
	Our primary business is the ownership, management, and redevelopment of retail and mixed-use properties. We review operating and financial information for each property on an individual basis and therefore, each property represents an individual operating segment. We evaluate financial performance using property operating income, which consists of rental income, other property income and mortgage interest income, less rental expenses and real estate taxes. No individual property constitutes more than 10% of our revenues or property operating income and we have no operations outside of the United States of America. Therefore, we have aggregated our properties into one reportable segment as the properties share similar long-term economic characteristics and have other similarities including the fact that they are operated using consistent business strategies, are typically located in major metropolitan areas, and have similar tenant mixes.
	Recently Adopted Accounting Pronouncements
	In April 2014, the FASB issued ASU 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity.” ASU 2014-08 amends the definition of a discontinued operation to include only the disposal of a component of an entity that represents a strategic shift that has or will have a major impact on an entity’s operations and financial results. The standard also requires additional disclosures about discontinued operations as well as disposal transactions that do not meet the discontinued operations criteria. The standard is applicable prospectively for all disposals initially classified as held for sale in periods after adoption. We adopted the standard effective January 1, 2014, and there was no impact to the current period financial statements.  In future periods, the adoption will result in most individual property disposals not qualifying for discontinued operations presentation and thus, the results of those disposals will remain in “income from continuing operations.”  Properties sold prior to January 1, 2014, are not subject to ASU 2014-08 and therefore, continue to be classified as discontinued operations using the previous definition.
	Recently Issued Accounting Pronouncements
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers." ASU 2014-09 supersedes nearly all existing revenue recognition guidance under GAAP and replaces it with a core revenue recognition principle, that an entity will recognize revenue when it transfers control of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services, and creates a five-step model for revenue recognition in accordance with this principle. ASU 2014-09 also requires new disclosures in both interim and annual reporting periods. The guidance in ASU 2014-09 does not apply to contracts within the scope of ASC 840, Leases. ASU 2014-09 will be effective for us in the first quarter of 2017 and allows for either full retrospective or modified retrospective adoption. We are currently assessing the impact of this standard to our consolidated financial statements.
	In August 2014, the FASB issued ASU 2014-15, “Disclosures of Uncertainties about an Entity’s Ability to Continue as a Going Concern.”  ASU 2014-15 provides guidance regarding management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and if such doubt exists, requires specific disclosures.  ASU 2014-15 is effective for us in the first quarter of 2017 and is not expected to have a significant impact on our consolidated financial statements.
	In January 2015, the FASB issued ASU 2015-01, "Income Statement - Extraordinary and Unusual Items." ASU 2015-01 eliminates the concept, and related presentation and disclosure requirements, of an extraordinary item. The presentation and disclosure guidance for items that are unusual in nature or occur infrequently will be retained and will be expanded to include those items that are both unusual in nature and infrequently occurring. ASU 2015-01 is effective for us in the first quarter of 2016 and is not expected to have a significant impact on our consolidated financial statements.
Consolidated Statements of Cash Flows—Supplemental Disclosures
The following table provides supplemental disclosures related to the Consolidated Statements of Cash Flows:
	Year Ended December 31,
	2014			2013			2012
	(In thousands)
SUPPLEMENTAL DISCLOSURES:
Total interest costs incurred	$	114,912		$	121,158		$	123,441
Interest capitalized	(20,971		)	(16,181		)	(10,105		)
Interest expense	$	93,941		$	104,977		$	113,336
Cash paid for interest, net of amounts capitalized	$	100,011		$	120,934		$	114,419
Cash paid (refunded) for income taxes	$	278		$	410		$	(1,151	)
NON-CASH INVESTING AND FINANCING TRANSACTIONS:
Mortgage loans assumed with acquisition	$	68,282		$	—		$	67,615
DownREIT operating partnership units issued with acquisition	$	65,348		$	—		$	—
Mortgage loans refinanced	$	64,205		$	—		$	—
Repayment of note payable with public funding/related construction-in-progress offset	$	10,000		$	—		$	—
Shares issued under dividend reinvestment plan	$	1,855		$	1,779		$	1,864
See Note 3 for additional disclosures relating to The Grove at Shrewsbury and Brook 35 acquisition.
Capitalized lease costs are direct costs incurred which were essential to originate a lease and would not have been incurred had the leasing transaction not taken place. These costs include third party commissions and salaries and personnel costs related to obtaining a lease. Capitalized lease costs are amortized over the initial term of the related lease which generally ranges from three to ten years. We view these lease costs as part of the up-front initial investment we made in order to generate a long-term cash inflow and therefore, we classify cash outflows related to leasing costs as an investing activity in our consolidated statements of cash flows.

Real_Estate

Real Estate	12 Months Ended
	Dec. 31, 2014
Real Estate [Abstract]
REAL ESTATE	REAL ESTATE
	A summary of our real estate investments and related encumbrances is as follows:
		Cost		Accumulated			Encumbrances
				Depreciation and
				Amortization
		(In thousands)
	December 31, 2014
	Retail and mixed-use properties	$	5,478,085	$	(1,423,682	)	$	541,568
	Retail properties under capital leases	121,069		(35,179		)	71,647
	Residential	9,844		(8,189		)	22,130
		$	5,608,998	$	(1,467,050	)	$	635,345
	December 31, 2013
	Retail and mixed-use properties	$	5,024,800	$	(1,310,791	)	$	565,935
	Retail properties under capital leases	115,028		(31,955		)	71,671
	Residential	9,635		(7,725		)	22,521
		$	5,149,463	$	(1,350,471	)	$	660,127
	Retail and mixed-use properties includes the residential portion of Santana Row, Bethesda Row, Pike & Rose, Congressional Plaza and Chelsea Commons. The residential property investment is our investment in Rollingwood Apartments.
	2014 Significant Property Acquisitions
	Effective January 1, 2014, we acquired a controlling interest in The Grove at Shrewsbury, a 187,000 square foot shopping center in Shrewsbury, New Jersey, and Brook 35, a 99,000 square foot shopping center in Sea Girt, New Jersey for a gross value of $161 million. Our effective economic interest approximates 84% and was funded by the assumption of our share of $68 million of mortgage debt, 632,000 downREIT operating partnership units, and $13 million of cash (which was in an escrow account at December 31, 2013). Approximately $1.7 million and $2.3 million of net assets acquired were allocated to other assets for "above market leases" and other liabilities for "below market leases," respectively. Additionally, $71.1 million was allocated to redeemable and nonredeemable noncontrolling interests. We incurred $2.0 million of acquisition costs, of which $1.0 million were incurred in 2014, and are included in "general and administrative expenses" in 2014 and 2013 on the accompanying consolidated statements of comprehensive income.
	We have entered into an agreement to acquire the interest of one of the noncontrolling interest holders in The Grove at Shrewsbury in 2015. As this noncontrolling interest is mandatorily redeemable, it has been classified as a liability of approximately $9 million and is included in "other liabilities and deferred credits" on the December 31, 2014 consolidated balance sheet. An additional noncontrolling interest holder has the right to require us to acquire its interests in The Grove at Shrewsbury and Brook 35 at the then current fair market value beginning on January 1, 2017.
	2013 Significant Property Acquisitions and Dispositions
	On April 3, 2013, we acquired the fee interest in a 95,000 square foot retail property located in Darien, Connecticut for $47.3 million. Approximately $0.1 million and $1.8 million of net assets acquired were allocated to other assets for "above market leases" and other liabilities for "below market leases", respectively. We incurred $0.2 million of acquisition costs which are included in "general and administrative expenses" in 2013.
	On April 5, 2013, one of our tenants acquired our fee interest in the land under an office building at our Village of Shirlington property in Arlington, Virginia, that was subject to a long term ground lease. The ground lease included an option for the tenant to purchase the fee interest. The sales price was $6.5 million, and the gain was $5.0 million.
	On July 22, 2013, we sold the fee interest in our final building at Fifth Avenue in San Diego, California, for a sales price of $15.3 million resulting in a gain of $10.7 million. On September 10, 2013 we sold the fee interest in a building in Forest Hills (Queens), New York, for a sales price of $20.4 million resulting in a gain of $13.2 million. Both sales were completed as a Section 1031 tax deferred exchange transaction with the acquisition of the property in Darien.
	On October 1, 2013, we acquired the fee interest in an 11.8 acre land parcel adjacent to our Assembly Row development project for a purchase price of $18.0 million.
	On December 19, 2013, we acquired the fee interest in a land parcel contiguous with our Montrose Crossing shopping center that is encumbered by two retail ground leases. The total purchase price was $10.5 million and our 89.9% share was $9.4 million.

Mortgage_Notes_Receivable

Mortgage Notes Receivable	12 Months Ended
	Dec. 31, 2014
Mortgage Notes Receivable [Abstract]
MORTGAGE NOTES RECEIVABLE	MORTGAGE NOTES RECEIVABLE
	At December 31, 2014 and 2013, we had four and five mortgage notes receivable with an aggregate carrying amount of $51.0 million and $55.2 million, respectively. Approximately $41.2 million and $44.8 million of the loans are secured by first mortgages on retail buildings at December 31, 2014 and 2013, respectively. One of the loans, which is secured by a second mortgage on a hotel at our Santana Row property, was considered impaired when it was amended in August 2006. At December 31, 2014 and 2013, the loan has an outstanding face amount of $10.7 million and $11.9 million, respectively, and is carried net of a valuation allowance of $1.0 million and $1.6 million, respectively. At December 31, 2014 and 2013, our mortgages had a weighted average interest rate of 9.0%. Under the terms of certain of these mortgages, we receive additional interest based upon the gross income of the secured properties and upon sale, share in the appreciation of the properties.

Real_Estate_Partnerships

Real Estate Partnerships	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
REAL ESTATE PARTNERSHIPS	REAL ESTATE PARTNERSHIPS
	Federal/Lion Venture LP
	We have a joint venture arrangement (the “Partnership”) with affiliates of a discretionary fund created and advised by ING Clarion Partners (“Clarion”). We own 30% of the equity in the Partnership and Clarion owns 70%. We hold a general partnership interest, however, Clarion also holds a general partnership interest and has substantive participating rights. We cannot make significant decisions without Clarion’s approval. Accordingly, we account for our interest in the Partnership using the equity method. As of December 31, 2014, the Partnership owned six retail real estate properties. We are the manager of the Partnership and its properties, earning fees for acquisitions, dispositions, management, leasing, and financing. Intercompany profit generated from fees is eliminated in consolidation. We also have the opportunity to receive performance-based earnings through our Partnership interest. Accounting policies for the Partnership are similar to accounting policies followed by the Trust. The Partnership is subject to a buy-sell provision which is customary for real estate joint venture agreements and the industry. Either partner may initiate this provision at any time, which could result in either the sale of our interest or the use of available cash or borrowings to acquire Clarion’s interest. As of December 31, 2014, we have made total contributions of $48.8 million and received total distributions of $30.4 million.
	The following tables provide summarized operating results and the financial position of the Partnership:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	OPERATING RESULTS
	Revenue	$	18,329	$	19,209	$	19,051
	Expenses
	Other operating expenses	5,948		5,999		5,234
	Depreciation and amortization	5,678		5,506		5,508
	Interest expense	2,759		3,363		3,376
	Total expenses	14,385		14,868		14,118
	Net income before gain on sale of real estate	3,944		4,341		4,933
	Gain on sale of real estate	14,507		—		—
	Net income	$	18,451	$	4,341	$	4,933
	Our share of net income from real estate partnership before gain on sale of real estate	$	1,423	$	1,498	$	1,815
	Our share of gain on sale of real estate	$	4,401	$	—	$	—
		December 31,
		2014		2013
		(In thousands)
	BALANCE SHEETS
	Real estate, net	$	149,203	$	170,867
	Cash	2,864		2,210
	Other assets	5,346		5,668
	Total assets	$	157,413	$	178,745
	Mortgages payable	$	34,385	$	56,922
	Other liabilities	3,673		4,100
	Partners’ capital	119,355		117,723
	Total liabilities and partners’ capital	$	157,413	$	178,745
	Our share of unconsolidated debt	$	10,316	$	17,077
	Our investment in real estate partnership	$	32,367	$	32,264
	On June 5, 2014, the Partnership repaid an $11.9 million mortgage loan secured by one of its properties at par prior to the original maturity date of July 5, 2014. The partners made additional capital contributions totaling $11.9 million to repay the mortgage loan, of which our contribution was $3.6 million.
	On July 24, 2014, the Partnership sold the fee interest in Pleasant Shops in Weymouth, Massachusetts for a sales price of $34.3 million, resulting in a gain on sale of $14.5 million. Our share of the gain was $4.4 million. The partners received distributions totaling $32.8 million as a result of the sale, of which our distribution was $10.4 million.
	On September 2, 2014, the Partnership repaid a $10.5 million mortgage loan secured by one of its properties at par prior to the original maturity date of December 1, 2014. The partners made additional capital contributions totaling $10.5 million to repay the mortgage loan, of which our contribution was $3.2 million.
	Taurus Newbury Street JV II Limited Partnership
	In May 2010, we formed Taurus Newbury Street JV II Limited Partnership ("Newbury Street Partnership"), a joint venture with an affiliate of Taurus Investment Holdings, LLC ("Taurus"), to acquire, operate and redevelop properties located primarily in the Back Bay section of Boston, Massachusetts. We held an 85% limited partnership interest in Newbury Street Partnership and Taurus held a 15% limited partnership interest and served as general partner. As general partner, Taurus was responsible for the operation and management of the properties, subject to our approval on major decisions. Accordingly, given Taurus' role as general partner, we accounted for our interest in Newbury Street Partnership using the equity method. Due to the timing of receiving financial information from the general partner, our share of earnings was recorded one quarter in arrears. On October 31, 2011, our Newbury Street Partnership sold its entire portfolio of three buildings for $44.0 million. Due to our earnings being recorded one quarter in arrears, we recognized the gain on sale of $11.9 million in the first quarter of 2012.

Acquired_InPlace_Leases

Acquired In-Place Leases	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
ACQUIRED IN-PLACE LEASES	ACQUIRED IN-PLACE LEASES
	Acquired above market leases are included in prepaid expenses and other assets and had a balance of $32.7 million and $31.1 million and accumulated amortization of $19.3 million and $16.3 million at December 31, 2014 and 2013, respectively. Acquired below market leases are included in other liabilities and deferred credits and had a balance of $109.8 million and $111.1 million and accumulated amortization of $37.0 million and $34.9 million at December 31, 2014 and 2013, respectively. The value allocated to in-place leases is amortized over the related lease term and reflected as additional rental income for below market leases or a reduction of rental income for above market leases in the consolidated statements of comprehensive income. Rental income included amortization from acquired above market leases of $3.4 million, $2.8 million and $3.4 million in 2014, 2013 and 2012, respectively and amortization from acquired below market leases of $5.8 million, $5.9 million and $4.5 million in 2014, 2013 and 2012, respectively. The remaining weighted-average amortization period as of December 31, 2014, is 5.1 years and 21.2 years for above market leases and below market leases, respectively.
	The amortization for acquired in-place leases during the next five years and thereafter, assuming no early lease terminations, is as follows:
		Above Market		Below Market
		Leases		Leases
		(In thousands)
	Year ending December 31,
	2015	$	2,892	$	5,327
	2016	2,476		4,898
	2017	1,784		4,653
	2018	1,275		3,706
	2019	923		3,610
	Thereafter	4,012		50,632
		$	13,362	$	72,826

Debt

Debt	12 Months Ended
	Dec. 31, 2014
Debt Instruments [Abstract]
DEBT	DEBT
	The following is a summary of our total debt outstanding as of December 31, 2014 and 2013:
				Principal Balance as of December 31,							Stated Interest Rate as of
	Description of Debt			2014				2013			December 31, 2014		Stated Maturity Date
	Mortgages payable			(Dollars in thousands)
	Melville Mall			$	—			$	20,705		5.25	%	September 1, 2014
	THE AVENUE at White Marsh			—				54,112			5.46	%	January 1, 2015
	Barracks Road			35,985				37,069			7.95	%	November 1, 2015
	Hauppauge			13,566				13,974			7.95	%	November 1, 2015
	Lawrence Park			25,507				26,275			7.95	%	November 1, 2015
	Wildwood			22,420				23,095			7.95	%	November 1, 2015
	Wynnewood			25,994				26,777			7.95	%	November 1, 2015
	Brick Plaza			26,415				27,254			7.42	%	November 1, 2015
	East Bay Bridge			—				61,980			5.13	%	March 1, 2016
	Plaza El Segundo			175,000				175,000			6.33	%	August 5, 2017
	The Grove at Shrewsbury (East)			44,519				—			5.82	%	October 1, 2017
	The Grove at Shrewsbury (West)			11,242				—			6.38	%	March 1, 2018
	Rollingwood Apartments			22,130				22,521			5.54	%	May 1, 2019
	29th Place			4,941				5,119			5.91	%	January 31, 2021
	THE AVENUE at White Marsh			52,705				—			3.35	%	January 1, 2022
	Montrose Crossing			75,867				77,341			4.2	%	January 10, 2022
	Brook 35			11,500				—			4.65	%	July 1, 2029
	Chelsea			7,074				7,269			5.36	%	January 15, 2031
	Subtotal			554,865				578,491
	Net unamortized premium			8,833				9,965
	Total mortgages payable			563,698				588,456
	Notes payable
	Escondido (municipal bonds)			9,400				9,400			0.06	%	October 1, 2016
	Revolving credit facility			—				—			LIBOR + 0.90%		April 21, 2017
	Term loan			275,000				275,000			LIBOR + 0.90%		November 21, 2018
	Various			6,119				16,422			11.31	%	Various through 2028
	Total notes payable			290,519				300,822
	Senior notes and debentures
	5.65% notes			—				125,000			5.65	%	June 1, 2016
	6.20% notes			200,000				200,000			6.2	%	January 15, 2017
	5.90% notes			150,000				150,000			5.9	%	April 1, 2020
	3.00% notes			250,000				250,000			3	%	August 1, 2022
	2.75% notes			275,000				275,000			2.75	%	June 1, 2023
	3.95% notes			300,000				300,000			3.95	%	January 15, 2024
	7.48% debentures			29,200				29,200			7.48	%	August 15, 2026
	6.82% medium term notes			40,000				40,000			6.82	%	August 1, 2027
	4.50% notes			250,000				—			4.5	%	December 1, 2044
	Subtotal			1,494,200				1,369,200
	Net unamortized discount			(10,387		)		(8,287		)
	Total senior notes and debentures			1,483,813				1,360,913
	Capital lease obligations
	Various			71,647				71,671			Various		Various through 2106
	Total debt and capital lease obligations			$	2,409,677			$	2,321,862
	In connection with the acquisition of The Grove at Shrewsbury and Brook 35 on January 1, 2014, we assumed mortgage loans with a face amount of $68.3 million and a fair value of $73.8 million. The mortgage loans are secured by the individual properties with the following contractual terms:
		Principal				Stated Interest Rate			Maturity Date
		(In millions)
	Brook 35 Plaza	$	11.5			5.46	%		July 1, 2014
	The Grove at Shrewsbury (East)	$	45.4			5.82	%		October 1, 2017
	The Grove at Shrewsbury (West)	$	11.4			6.38	%		March 1, 2018
	During 2014, we refinanced or issued the following loans or debt securities:
			Amount				Stated Interest Rate			Refinance/Issuance Date	Maturity Date
			(In millions)
	Brook 35 Plaza Mortgage Loan	Refinance	$	11.5			4.65	%		June 2, 2014	July 1, 2029
	4.50% Senior Notes (1)	Issuance	$	250			4.5	%		November 14, 2014	December 1, 2044
	THE AVENUE at White Marsh Mortgage Loan	Refinance	$	52.7			3.35	%		December 15, 2014	January 1, 2022
	(1) The net proceeds from this note offering after issuance discounts, underwriting fees and other costs were approximately $244.6 million.
	During 2014, we fully repaid or redeemed the following loans or debt securities:
			Payoff Amount				Repayment Date		Maturity Date
			(In millions)
Melville Mall Mortgage Loan		$	20.3			June 3, 2014		September 1, 2014
East Bay Bridge Mortgage Loan (1)		$	61			December 10, 2014		March 1, 2016
5.65% Senior Notes (2)		$	125			December 12, 2014		June 1, 2016
(1) The total amount due at payoff of $64.0 million included a prepayment premium of $3.0 million and accrued but unpaid interest of $0.1 million. The prepayment premium is included in "early extinguishment of debt" in 2014.
(2) The redemption price of $134.5 million included a make-whole premium of approximately $9.2 million and accrued but unpaid interest of $0.2 million. The make-whole premium is included in "early extinguishment of debt" in 2014.
On August 28, 2014, we amended our term loan agreement and lowered the spread over LIBOR by 40 basis points from 130 basis points to 90 basis points based on our current credit rating. The amendment also provides us the option to extend the maturity date by one year.
During 2014, 2013 and 2012, the maximum amount of borrowings outstanding under our revolving credit facility was $79.5 million, $76.0 million and $186.0 million, respectively. The weighted average amount of borrowings outstanding was $12.5 million, $10.5 million and $1.5 million, respectively, and the weighted average interest rate, before amortization of debt fees, was 1.1%, 1.3% and 1.4%, respectively. The revolving credit facility requires an annual facility fee of $0.9 million. At December 31, 2014 and 2013, our revolving credit facility had no balance outstanding.
Our revolving credit facility and certain notes require us to comply with various financial covenants, including the maintenance of minimum shareholders’ equity and debt coverage ratios and a maximum ratio of debt to net worth. As of December 31, 2014, we were in compliance with all loan covenants.
Scheduled principal payments on mortgages payable, notes payable, senior notes and debentures as of December 31, 2014 are as follows:
	Mortgages					Notes				Senior Notes and			Total
	Payable					Payable				Debentures			Principal
	(In thousands)
Year ending December 31,
2015	$	153,395				$	369			$	—		$	153,764
2016	3,774					9,806				—			13,580
2017	220,438					451			-1	200,000			420,889
2018	13,326					275,500				—			288,826
2019	22,731					553				—			23,284
Thereafter	141,201					3,840				1,294,200			1,439,241
	$	554,865				$	290,519			$	1,494,200		$	2,339,584	-2
_____________________
-1	Our $600.0 million revolving credit facility matures on April 21, 2017, subject to a one-year extension at our option. As of December 31, 2014, there was no balance outstanding under this credit facility.
-2	The total debt maturities differ from the total reported on the consolidated balance sheet as of December 31, 2014 due to the unamortized discount or premium on certain senior notes and mortgages payable.
Future minimum lease payments and their present value for property under capital leases as of December 31, 2014, are as follows:
	(In thousands)
Year ending December 31,
2015	$	5,787
2016	5,788
2017	5,797
2018	5,800
2019	5,800
Thereafter	160,210
	189,182
Less amount representing interest	(117,535		)
Present value	$	71,647

Fair_Value_Of_Financial_Instru

Fair Value Of Financial Instruments	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	FAIR VALUE OF FINANCIAL INSTRUMENTS
	A fair value measurement is based on the assumptions that market participants would use in pricing an asset or liability in an orderly transaction. The hierarchy for inputs used in measuring fair value are as follows:
	1	Level 1 Inputs—quoted prices in active markets for identical assets or liabilities
	2	Level 2 Inputs—observable inputs other than quoted prices in active markets for identical assets and liabilities
	3	Level 3 Inputs—prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable
	In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the level within which the fair value measurement is categorized is based on the lowest level input that is significant to the fair value measurement.
	Except as disclosed below, the carrying amount of our financial instruments approximates their fair value. The fair value of our mortgages payable, notes payable and senior notes and debentures is sensitive to fluctuations in interest rates. Quoted market prices (Level 1) were used to estimate the fair value of our marketable senior notes and debentures and discounted cash flow analysis (Level 2) is generally used to estimate the fair value of our mortgages and notes payable. Considerable judgment is necessary to estimate the fair value of financial instruments. The estimates of fair value presented herein are not necessarily indicative of the amounts that could be realized upon disposition of the financial instruments. A summary of the carrying amount and fair value of our mortgages payable, notes payable and senior notes and debentures is as follows:
		December 31, 2014				December 31, 2013
		Carrying		Fair Value		Carrying		Fair Value
		Value				Value
		(In thousands)
	Mortgages and notes payable	$	854,217	$	880,866	$	889,278	$	912,251
	Senior notes and debentures	$	1,483,813	$	1,579,868	$	1,360,913	$	1,397,731
	As of December 31, 2014, we have two interest rate swap agreements with a notional amount of $275.0 million that are measured at fair value on a recurring basis. The interest rate swap agreements fix the variable portion of our $275.0 million term loan at 1.72% from December 1, 2011 through November 1, 2018. The fair values of the interest rate swap agreements are based on the estimated amounts we would receive or pay to terminate the contracts at the reporting date and are determined using interest rate pricing models and interest rate related observable inputs. The fair value of our swaps at December 31, 2014 and 2013, was a liability of $3.5 million, and $1.4 million, respectively, and are included in "accounts payable and accrued expenses" on our consolidated balance sheets. The changes in valuation on our interest rate swaps were a $2.1 million decrease and an $11.0 million increase (including $4.3 million for both years reclassified from other comprehensive loss to earnings) for 2014 and 2013, and are included in "accumulated other comprehensive loss". A summary of our financial liabilities that are measured at fair value on a recurring basis, by level within the fair value hierarchy is as follows:
		December 31, 2014								December 31, 2013
		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
		(In thousands)
	Interest rate swaps	$	—	$	3,515	$	—	$	3,515	$	—	$	1,417	$	—	$	1,417

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES
	We are sometimes involved in lawsuits, warranty claims, and environmental matters arising in the ordinary course of business. Management makes assumptions and estimates concerning the likelihood and amount of any potential loss relating to these matters.
	We are currently a party to various legal proceedings. We accrue a liability for litigation if an unfavorable outcome is probable and the amount of loss can be reasonably estimated. If an unfavorable outcome is probable and a reasonable estimate of the loss is a range, we accrue the best estimate within the range; however, if no amount within the range is a better estimate than any other amount, the minimum within the range is accrued. Legal fees related to litigation are expensed as incurred. Other than as described below, we do not believe that the ultimate outcome of these matters, either individually or in the aggregate, could have a material adverse effect on our financial position or overall trends in results of operations; however, litigation is subject to inherent uncertainties. Also under our leases, tenants are typically obligated to indemnify us from and against all liabilities, costs and expenses imposed upon or asserted against us (1) as owner of the properties due to certain matters relating to the operation of the properties by the tenant, and (2) where appropriate, due to certain matters relating to the ownership of the properties prior to their acquisition by us.
	We reserve for estimated losses, if any, associated with warranties given to a buyer at the time real estate is sold or other potential liabilities relating to that sale, taking any insurance policies into account. These warranties may extend up to ten years and require significant judgment. If changes in facts and circumstances indicate that warranty reserves are understated, we will accrue additional reserves at such time a liability has been incurred and the costs can be reasonably estimated. Warranty reserves are released once the legal liability period has expired or all related work has been substantially completed. Any increases to our estimated warranty losses would usually result in a decrease in net income.
	We are self-insured for general liability costs up to predetermined retained amounts per claim, and we believe that we maintain adequate accruals to cover our retained liability. We currently do not maintain third party stop-loss insurance policies to cover liability costs in excess of predetermined retained amounts. Our accrual for self-insurance liability is determined by management and is based on claims filed and an estimate of claims incurred but not yet reported. Management considers a number of factors, including third-party actuarial analysis and future increases in costs of claims, when making these determinations. If our liability costs exceed these accruals, it will reduce our net income.
	At December 31, 2014 and 2013, our reserves for warranties and general liability costs were $7.2 million and $7.4 million, respectively, and are included in “accounts payable and accrued expenses” in our consolidated balance sheets. Any potential losses which exceed our estimates would result in a decrease in our net income. During 2014 and 2013, we made payments from these reserves of $1.4 million and $1.2 million, respectively. Although we consider the reserve to be adequate, there can be no assurance that the reserve will prove to be adequate over-time to cover losses due to the difference between the assumptions used to estimate the reserve and actual losses.
	At December 31, 2014, we had letters of credit outstanding of approximately $13.0 million which are collateral for existing indebtedness and other obligations of the Trust.
	As of December 31, 2014 in connection with capital improvement, development, and redevelopment projects, the Trust has contractual obligations of approximately $232.3 million.
	We are obligated under ground lease agreements on several shopping centers requiring minimum annual payments as follows, as of December 31, 2014:
		(In thousands)
	Year ending December 31,
	2015	$	1,478
	2016	2,437
	2017	2,473
	2018	2,488
	2019	2,676
	Thereafter	154,211
		$	165,763
	A master lease for Mercer Mall includes a fixed purchase price option for $55 million in 2023. If we fail to exercise our purchase option, the owner of Mercer Mall has a put option which would require us to purchase Mercer Mall for $60 million in 2025.
	Under the terms of the Congressional Plaza partnership agreement, from and after January 1, 1986, an unaffiliated third party has the right to require us and the other minority partner to purchase its 29.47% interest in Congressional Plaza at the interest’s then-current fair market value. If the other minority partner defaults in their obligation, we must purchase the full interest. Based on management’s current estimate of fair market value as of December 31, 2014, our estimated maximum liability upon exercise of the put option would range from approximately $72 million to $76 million.
	Under the terms of a partnership which owns a project in southern California, if certain leasing and revenue levels are obtained for the property owned by the partnership, the other partner may require us to purchase their 10% partnership interest at a formula price based upon property operating income. The purchase price for the partnership interest will be paid using our common shares or, subject to certain conditions, cash. If the other partner does not redeem their interest, we may choose to purchase the partnership interest upon the same terms.
	A master lease for Melville Mall includes a fixed purchase price option in 2021 for $5 million. If we fail to exercise our purchase option, the owner of Melville Mall has a put option which would require us to purchase Melville Mall in 2023 for $5 million.
	The other member in Montrose Crossing has the right to require us to purchase all of its 10.1% interest in Montrose Crossing at the interest's then-current fair market value. If the other member fails to exercise its put option, we have the right to purchase its interest on or after December 27, 2021 at fair market value. Based on management’s current estimate of fair market value as of December 31, 2014, our estimated maximum liability upon exercise of the put option would range from approximately $9 million to $10 million.
	Two of the members in Plaza El Segundo have the right to require us to purchase their 10.0% and 11.8% ownership interests at the interests' then-current fair market value. If the members fail to exercise their put options, we have the right to purchase each of their interests on or after December 30, 2026 at fair market value. Based on management’s current estimate of fair market value as of December 31, 2014, our estimated maximum liability upon exercise of the put option would range from approximately $18 million to $21 million. Also, between January 1, 2017 and February 1, 2017, we have an option to purchase the preferred interest of another member in Plaza El Segundo. The purchase price will be the lesser of fair value or the $4.9 million stated value of the preferred interest plus any accrued and unpaid preferred returns.
	Effective January 1, 2017, the other member in The Grove at Shrewsbury and Brook 35 has the right to require us to purchase all of its approximately 4.8% interest in The Grove at Shrewsbury and approximately 8.8% interest in Brook 35 at the interests' then-current fair market value.
	Under the terms of certain partnership agreements, the partners have the right to exchange their operating partnership units for cash or the same number of our common shares, at our option. A total of 917,255 operating partnership units are outstanding which have a total fair value of $122.4 million, based on our closing stock price on December 31, 2014.

Shareholders_Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2014
Stockholders' Equity Note [Abstract]
SHAREHOLDERS’ EQUITY	SHAREHOLDERS’ EQUITY
	We have a Dividend Reinvestment Plan (the “Plan”), whereby shareholders may use their dividends and optional cash payments to purchase shares. In 2014, 2013 and 2012, 18,705 shares, 20,026 shares and 22,814 shares, respectively, were issued under the Plan.
	As of December 31, 2014, 2013, and 2012, we had 399,896 shares of 5.417% Series 1 Cumulative Convertible Preferred Shares (“Series 1 Preferred Shares”) outstanding that have a liquidation preference of $25 per share and
	par value $0.01 per share. The Series 1 Preferred Shares accrue dividends at a rate of 5.417% per year and are convertible at any time by the holders to our common shares at a conversion rate of $104.69 per share. The Series 1 Preferred Shares are also convertible under certain circumstances at our election. The holders of the Series 1 Preferred Shares have no voting rights.
	On February 12, 2014 we replaced our existing at the market (“ATM”) equity program with a new ATM equity program in which we may from time to time offer and sell common shares having an aggregate offering price of up to $300.0 million. We intend to use the net proceeds to fund potential acquisition opportunities, fund our development and redevelopment pipeline, repay amounts of outstanding under our revolving credit facility and/or for general corporate purposes. For the year ended December 31, 2014, we issued 1,768,583 common shares at a weighted average price per share of $122.09 for net cash proceeds of $213.6 million and paid $2.2 million in commissions and $0.2 million in additional offering expenses related to the sales of these common shares. For the year ended December 31, 2013, we issued 1,734,974 common shares at a weighted average price per share of $108.01 for net cash proceeds of $185.2 million and paid $2.0 million in commissions and $0.2 million in additional offering expenses related to the sales of these common shares. As of December 31, 2014, we had the capacity to issue up to $84.1 million in common shares under our ATM equity program.

Dividends

Dividends	12 Months Ended
	Dec. 31, 2014
Dividends [Abstract]
DIVIDENDS	DIVIDENDS
	The following table provides a summary of dividends declared and paid per share:
		Year Ended December 31,
		2014				2013				2012
		Declared		Paid		Declared		Paid		Declared		Paid
	Common shares	$	3.3	$	3.21	$	3.02	$	2.97	$	2.84	$	2.8
	5.417% Series 1 Cumulative Convertible Preferred shares	$	1.354	$	1.354	$	1.354	$	1.354	$	1.354	$	1.354
	A summary of the income tax status of dividends per share paid is as follows:
		Year Ended December 31,
		2014		2013		2012
	Common shares
	Ordinary dividend	$	3.178	$	2.911	$	2.772
	Capital gain	0.032		0.059		0.028
		$	3.21	$	2.97	$	2.8
	5.417% Series 1 Cumulative Convertible Preferred shares
	Ordinary dividend	$	1.34	$	1.327	$	1.34
	Capital gain	0.014		0.027		0.014
		$	1.354	$	1.354	$	1.354
	On October 30, 2014, the Trustees declared a quarterly cash dividend of $0.87 per common share, payable January 15, 2015 to common shareholders of record on January 2, 2015.

Operating_Leases

Operating Leases	12 Months Ended
	Dec. 31, 2014
Leases [Abstract]
OPERATING LEASES	OPERATING LEASES
	At December 31, 2014, our 89 predominantly retail shopping center and mixed-use properties are located in 13 states and the District of Columbia. There are approximately 2,700 leases with tenants providing a wide range of retail products and services. These tenants range from sole proprietorships to national retailers; no one tenant or corporate group of tenants accounts for more than 3.1% of annualized base rent.
	Our leases with commercial property and residential tenants are classified as operating leases. Commercial property leases generally range from three to ten years (certain leases with anchor tenants may be longer), and in addition to minimum rents, may provide for percentage rents based on the tenant’s level of sales achieved and cost recoveries for the tenant’s share of certain operating costs. Leases on apartments are generally for a period of 1 year or less.
	As of December 31, 2014, minimum future commercial property rentals from noncancelable operating leases, before any reserve for uncollectible amounts and assuming no early lease terminations, at our operating properties are as follows:
		(In thousands)
	Year ending December 31,
	2015	$	484,911
	2016	447,519
	2017	389,507
	2018	323,748
	2019	268,600
	Thereafter	1,718,254
		$	3,632,539

Components_Of_Rental_Income

Components Of Rental Income	12 Months Ended
	Dec. 31, 2014
Components Of Rental Income and Expense [Abstract]
COMPONENTS OF RENTAL INCOME AND EXPENSE	COMPONENTS OF RENTAL INCOME AND EXPENSE
	The principal components of rental income are as follows:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	Minimum rents
	Retail and commercial	$	472,602	$	448,058	$	420,989
	Residential	36,099		28,902		27,611
	Cost reimbursement	135,592		122,578		112,424
	Percentage rent	10,169		9,359		8,568
	Other	11,860		11,192		10,522
	Total rental income	$	666,322	$	620,089	$	580,114
	Minimum rents include the following:
		Year Ended December 31,
		2014		2013		2012
		(In millions)
	Straight-line rents	$	5.1	$	5.4	$	6.1
	Net amortization of above and below market leases	$	2.4	$	3.1	$	1.1
	The principal components of rental expenses are as follows:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	Repairs and maintenance	$	55,444	$	46,600	$	41,550
	Utilities	20,499		19,219		19,201
	Management fees and costs	17,416		16,250		15,167
	Payroll	11,554		9,237		8,691
	Marketing	9,532		8,664		7,321
	Insurance	6,462		6,811		6,267
	Ground Rent	1,952		1,916		2,189
	Bad debt expense	2,021		442		2,173
	Other operating	10,537		9,556		10,057
	Total rental expenses	$	135,417	$	118,695	$	112,616

Discontinued_Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
DISCONTINUED OPERATIONS	DISCONTINUED OPERATIONS
	During 2013 and prior to our adoption of ASU 2014-08 as further discussed in Note 2, certain disposal transactions were considered discontinued operations. A summary of the financial information for the discontinued operations is as follows:
		Year Ended December 31,
		2013		2012
		(in millions)
	Revenue from discontinued operations	$	1.5	$	2.2
	Income from discontinued operations	$	0.9	$	1.4

ShareBased_Compensation_Plans

Share-Based Compensation Plans	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
SHARE-BASED COMPENSATION PLANS	SHARE-BASED COMPENSATION PLANS
	A summary of share-based compensation expense included in net income is as follows:
		Year Ended December 31,
		2014				2013				2012
		(In thousands)
	Share-based compensation incurred
	Grants of common shares	$	12,892			$	10,907			$	9,846
	Grants of options	49				292				525
		12,941				11,199				10,371
	Capitalized share-based compensation	(1,188		)		(1,024		)		(908		)
	Share-based compensation expense	$	11,753			$	10,175			$	9,463
	As of December 31, 2014, we have grants outstanding under two share-based compensation plans. In May 2010, our shareholders approved the 2010 Performance Incentive Plan, as amended (“the 2010 Plan”), which authorized the grant of share options, common shares and other share-based awards for up to 2,450,000 common shares of beneficial interest. Our 2001 Long Term Incentive Plan (the “2001 Plan”), which expired in May 2010, authorized the grant of share options, common shares and other share-based awards of 3,250,000 common shares of beneficial interest.
	Option awards under both plans are required to have an exercise price at least equal to the closing trading price of our common shares on the date of grant. Options and restricted share awards under these plans generally vest over three to six years and option awards typically have a ten-year contractual term. We pay dividends on unvested shares. Certain options and share awards provide for accelerated vesting if there is a change in control. Additionally, the vesting on certain option and share awards can accelerate in part or in full upon retirement based on the age of the retiree or upon termination without cause.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes model. Expected volatilities, term, dividend yields, employee exercises and estimated forfeitures are primarily based on historical data. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant. The fair value of each share award is determined based on the closing trading price of our common shares on the grant date. No options were granted in 2014, 2013 and 2012. The following table provides a summary of option activity for 2014:
		Shares			Weighted-				Weighted-		Aggregate
		Under			Average				Average		Intrinsic
		Option			Exercise				Remaining		Value
					Price				Contractual Term
									(In years)		(In thousands)
	Outstanding at December 31, 2013	375,460			$	63
	Granted	—			—
	Exercised	(29,218	)		73.38
	Forfeited or expired	(2,500	)		82.15
	Outstanding at December 31, 2014	343,742			$	61.55			3.4		$	24,719
	Exercisable at December 31, 2014	343,599			$	61.55			3.4		$	24,709
	The total cash received from options exercised during 2014, 2013 and 2012 was $2.3 million, $1.0 million and $5.7 million, respectively. The total intrinsic value of options exercised during the years ended December 31, 2014, 2013 and 2012 was $1.1 million, $0.7 million and $4.2 million, respectively.
	The following table provides a summary of restricted share activity for 2014:
		Shares			Weighted-Average
					Grant-Date Fair
					Value
	Unvested at December 31, 2013	298,203			$	93.71
	Granted	119,677			111.45
	Vested	(108,882	)		94.12
	Forfeited	(2,030	)		98.02
	Unvested at December 31, 2014	306,968			$	100.45
	The weighted-average grant-date fair value of stock awarded in 2014, 2013 and 2012 was $111.45, $106.70 and $96.35, respectively. The total vesting-date fair value of shares vested during the year ended December 31, 2014, 2013 and 2012, was $12.1 million, $10.6 million and $10.3 million, respectively.
	As of December 31, 2014, there was $15.5 million of total unrecognized compensation cost related to unvested share-based compensation arrangements (i.e. options and unvested shares) granted under our plans. This cost is expected to be recognized over the next 9.4 years with a weighted-average period of 2.1 years.
	Subsequent to December 31, 2014, common shares were awarded under various compensation plans as follows:
	Date		Award				Vesting Term		Beneficiary
	6-Feb-15		50,734		Restricted shares		2-5 years		Officers and key employees
	2-Jan-15		5,059		Shares		Immediate		Trustees

Savings_and_Retirement_Plans

Savings and Retirement Plans	12 Months Ended
	Dec. 31, 2014
Savings and Retirement Plans [Abstract]
SAVINGS AND RETIREMENT PLANS	SAVINGS AND RETIREMENT PLANS
	We have a savings and retirement plan in accordance with the provisions of Section 401(k) of the Code. Generally, employees can elect, at their discretion, to contribute a portion of their compensation up to a maximum of $17,500 for 2014 and 2013, and $17,000 for 2012. Under the plan, we contribute 50% of each employee’s elective deferrals up to 5% of eligible earnings. In addition, we may make discretionary contributions within the limits of deductibility set forth by the Code. Our full-time employees are immediately eligible to become plan participants. Employees are eligible to receive matching contributions immediately on their participation; however, these matching payments will not vest until their third anniversary of employment for new employees who joined the Trust after December 31, 2011, and their first anniversary of employment for all other participants. Our expense for the years ended December 31, 2014, 2013 and 2012 was approximately $442,000, $384,000 and $427,000, respectively.
	A non-qualified deferred compensation plan for our officers and certain other employees was established in 1994 that allows the participants to defer a portion of their income. As of December 31, 2014 and 2013, we are liable to participants for approximately $10.3 million and $9.2 million, respectively, under this plan. Although this is an unfunded plan, we have purchased certain investments to match this obligation. Our obligation under this plan and the related investments are both included in the accompanying consolidated financial statements.

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE
	We have calculated earnings per share (“EPS”) under the two-class method. The two-class method is an earnings allocation methodology whereby EPS for each class of common stock and participating securities is calculated according to dividends declared and participation rights in undistributed earnings. For 2014, 2013 and 2012, we had 0.3 million weighted average unvested shares outstanding, which are considered participating securities. Therefore, we have allocated our earnings for basic and diluted EPS between common shares and unvested shares; the portion of earnings allocated to the unvested shares is reflected as “earnings allocated to unvested shares” in the reconciliation below.
	In the dilutive EPS calculation, dilutive stock options were calculated using the treasury stock method consistent with prior periods. There were no anti-dilutive stock options in 2014, 2013, or 2012. The conversions of downREIT operating partnership units and 5.417% Series 1 Cumulative Convertible Preferred Shares are anti-dilutive for all periods presented and accordingly, have been excluded from the weighted average common shares used to compute diluted EPS.
		Year Ended December 31,
		2014			2013			2012
		(In thousands, except per share data)
	NUMERATOR
	Income from continuing operations	$	167,888		$	137,811		$	142,972
	Less: Preferred share dividends	(541		)	(541		)	(541		)
	Less: Income from continuing operations attributable to noncontrolling interests	(7,754		)	(4,927		)	(4,307		)
	Less: Earnings allocated to unvested shares	(1,003		)	(889		)	(845		)
	Income from continuing operations available for common shareholders	158,590			131,454			137,279
	Results from discontinued operations attributable to the Trust	—			24,803			1,400
	Gain on sale of real estate	4,401			4,994			11,860
	Net income available for common shareholders, basic and diluted	$	162,991		$	161,251		$	150,539
	DENOMINATOR
	Weighted average common shares outstanding—basic	67,322			65,331			63,881
	Effect of dilutive securities:
	Stock options	170			152			175
	Weighted average common shares outstanding—diluted	67,492			65,483			64,056
	EARNINGS PER COMMON SHARE, BASIC
	Continuing operations	$	2.35		$	2.01		$	2.15
	Discontinued operations	—			0.38			0.02
	Gain on sale of real estate	0.07			0.08			0.19
		$	2.42		$	2.47		$	2.36
	EARNINGS PER COMMON SHARE, DILUTED
	Continuing operations	$	2.34		$	2		$	2.14
	Discontinued operations	—			0.38			0.02
	Gain on sale of real estate	0.07			0.08			0.19
		$	2.41		$	2.46		$	2.35
	Income from continuing operations attributable to the Trust	$	160,134		$	132,884		$	138,665

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)
	Summarized quarterly financial data is as follows:
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
		(In thousands, except per share data)
	2014
	Revenue	$	170,828	$	167,947	$	170,938	$	176,377
	Operating income	$	63,444	$	68,361	$	67,622	$	71,610
	Net income(1)	$	40,545	$	45,416	$	49,049	$	37,279
	Net income attributable to the Trust(1)	$	38,753	$	43,545	$	47,075	$	35,162
	Net income available for common shareholders(1)	$	38,618	$	43,410	$	46,939	$	35,027
	Earnings per common share—basic(1)	$	0.58	$	0.64	$	0.69	$	0.51
	Earnings per common share—diluted(1)	$	0.57	$	0.64	$	0.69	$	0.51
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
		(In thousands, except per share data)
	2013
	Revenue(2)	$	157,149	$	157,388	$	159,030	$	163,846
	Operating income	$	62,502	$	63,488	$	64,701	$	63,470
	Net income(1)	$	35,842	$	38,797	$	63,366	$	29,603
	Net income attributable to the Trust(1)	$	34,588	$	37,539	$	62,098	$	28,456
	Net income available for common shareholders(1)	$	34,453	$	37,404	$	61,962	$	28,321
	Earnings per common share—basic(1)	$	0.53	$	0.57	$	0.94	$	0.43
	Earnings per common share—diluted(1)	$	0.53	$	0.57	$	0.94	$	0.42
	-1	Third quarter 2014 includes a $4.4 million gain on sale reflecting our share of the Partnership's sale of Pleasant Shops as further discussed in Note 5. Third quarter 2013 includes a $23.9 million gain on sale of two retail buildings as further discussed in Note 3.
	-2	Revenue in 2013 has been reduced to reflect the results of discontinued operations as further discussed in Note 14. Revenue from discontinued operations, by quarter, is summarized as follows:
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
		(In thousands)
	2013 revenue from discontinued operations	$	602	$	559	$	385	$	—

Subsequent_Event

Subsequent Event	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
SUBSEQUENT EVENT	SUBSEQUENT EVENT
	In January 2015, we acquired a controlling interest in San Antonio Center, a 376,000 square foot shopping center in Mountain View, California based on a total value of $62.2 million. Our effective interest approximates 80% and was funded by the assumption of our share of $18.7 million of mortgage debt, which has a stated interest rate of 5.27% and matures on January 1, 2016, approximately 58,000 downREIT operating partnership units and approximately $27 million of cash. We incurred $0.7 million of acquisition costs in 2014 which are included in "general and administrative expenses."

Schedule_III_Summary_of_Real_E

Schedule III - Summary of Real Estate and Accumulated Depreciation	12 Months Ended
	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Schedule III - Summary of Real Estate and Accumulated Depreciation	FEDERAL REALTY INVESTMENT TRUST
	SCHEDULE III
	SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
	31-Dec-14
	(Dollars in thousands)
	COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
	Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
											Capitalized		close of period						Depreciation		of	Acquired	depreciation
											Subsequent								and		Construction		in latest
											to								Amortization				income
											Acquisition												statements is
							Land		Building and				Land		Building and		Total						computed
									Improvements						Improvements
	150 POST STREET (California)		CA		$	—	$	11,685	$	9,181	$	16,350	$	11,685	$	25,531	$	37,216	$	16,363	1908/1965	10/23/97	35 years
	29TH PLACE (Virginia)		VA		4,917		10,211		18,863		11,222		10,225		30,071		40,296		7,323		1975 - 2001	5/30/07	35 years
	ANDORRA (Pennsylvania)		PA		—		2,432		12,346		10,875		2,432		23,221		25,653		17,090		1953	1/12/88	35 years
	ASSEMBLY ROW/ASSEMBLY SQUARE MARKETPLACE (Massachusetts)		MA		—		93,252		34,196		305,854		93,252		340,050		433,302		21,953		2005, 2012-2014	2005-2013	35 years
	THE AVENUE AT WHITE MARSH (Maryland)		MD		52,705		20,682		72,432		4,514		20,685		76,943		97,628		22,282		1997	3/8/07	35 years
	BALA CYNWYD (Pennsylvania)		PA		—		3,565		14,466		22,187		3,566		36,652		40,218		16,281		1955	9/22/93	35 years
	BARRACKS ROAD (Virginia)		VA		35,985		4,363		16,459		39,643		4,363		56,102		60,465		37,539		1958	12/31/85	35 years
	BETHESDA ROW (Maryland)		MD		—		46,579		35,406		141,226		44,880		178,331		223,211		56,776		1945-2008	12/31/93, 6/2/97, 1/20/06, 9/25/08, 9/30/08, & 12/27/10	35 - 50 years
	BRICK PLAZA (New Jersey)		NJ		26,415		—		24,715		35,770		3,944		56,541		60,485		42,119		1958	12/28/89	35 years
	BRISTOL PLAZA (Connecticut)		CT		—		3,856		15,959		9,602		3,856		25,561		29,417		14,521		1959	9/22/95	35 years
	BROOK 35 (New Jersey)		NJ		11,500		7,128		38,355		573		7,128		38,928		46,056		1,312		1986/2004	1/1/14	35 years
	CHELSEA COMMONS (Massachusetts)		MA		6,790		9,417		19,466		13,825		9,396		33,312		42,708		5,484		1962/1969/2008	8/25/06, 1/30/07, & 7/16/08	35 years
	COLORADO BLVD (California)		CA		—		5,262		4,071		8,787		5,262		12,858		18,120		9,336		1905-1988	12/31/96 & 8/14/98	35 years
	CONGRESSIONAL PLAZA (Maryland)		MD		—		2,793		7,424		69,801		1,020		78,998		80,018		47,425		1965/2003	4/1/65	35 years
	COURTHOUSE CENTER (Maryland)		MD		—		1,750		1,869		1,142		1,750		3,011		4,761		1,589		1975	12/17/97	35 years
	COURTYARD SHOPS (Florida)		FL		—		16,862		21,851		2,025		16,894		23,844		40,738		5,731		1990/1998	9/4/08	35 years
	CROSSROADS (Illinois)		IL		—		4,635		11,611		14,897		4,635		26,508		31,143		14,056		1959	7/19/93	35 years
	FEDERAL REALTY INVESTMENT TRUST
	SCHEDULE III
	SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
	31-Dec-14
	(Dollars in thousands)
	COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
	Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
											Capitalized		close of period						Depreciation		of	Acquired	depreciation
											Subsequent								and		Construction		in latest
											to								Amortization				income
											Acquisition												statements is
							Land		Building and				Land		Building and		Total						computed
									Improvements						Improvements
	CROW CANYON COMMONS (California)		CA		—		27,245		54,575		4,915		27,245		59,490		86,735		15,878		Late 1970's/	12/29/05 & 2/28/07	35 years
																					1998/2006
	DARIEN (Connecticut)		CT		—		29,809		18,302		21		29,809		18,323		48,132		1,134		1920-2009	4/3/13	35 years
	DEDHAM PLAZA (Massachusetts)		MA		—		12,287		12,918		9,834		12,287		22,752		35,039		12,909		1959	12/31/93	35 years
	DEL MAR VILLAGE (Florida)		FL		—		15,624		41,712		2,494		15,587		44,243		59,830		15,971		1982/1994/2007	5/30/08, 7/11/08, & 10/14/14	35 years
	EAST BAY BRIDGE (California)		CA		—		29,079		138,035		1,395		29,079		139,430		168,509		9,604		1994-2001, 2011/2012	12/21/12	35 years
	EASTGATE (North Carolina)		NC		—		1,608		5,775		20,329		1,608		26,104		27,712		17,343		1963	12/18/86	35 years
	ELLISBURG (New Jersey)		NJ		—		4,028		11,309		18,818		4,013		30,142		34,155		17,344		1959	10/16/92	35 years
	ESCONDIDO PROMENADE (California)		CA		—		19,117		15,829		12,118		19,117		27,947		47,064		12,034		1987	12/31/96 & 11/10/10	35 years
	FALLS PLAZA (Virginia)		VA		—		1,798		1,270		9,787		1,819		11,036		12,855		7,607		1960/1962	9/30/67 & 10/05/72	25 years
	FEDERAL PLAZA (Maryland)		MD		—		10,216		17,895		37,699		10,216		55,594		65,810		37,299		1970	6/29/89	35 years
	FINLEY SQUARE (Illinois)		IL		—		9,252		9,544		13,829		9,252		23,373		32,625		16,607		1974	4/27/95	35 years
	FLOURTOWN (Pennsylvania)		PA		—		1,345		3,943		9,010		1,345		12,953		14,298		4,490		1957	4/25/80	35 years
	FRESH MEADOWS (New York)		NY		—		24,625		25,255		30,115		24,633		55,362		79,995		30,687		1946-1949	12/5/97	35 years
	FRIENDSHIP CENTER (District of Columbia)		DC		—		12,696		20,803		3,999		12,696		24,802		37,498		8,889		1998	9/21/01	35 years
	GAITHERSBURG SQUARE (Maryland)		MD		—		7,701		5,271		12,810		5,973		19,809		25,782		15,980		1966	4/22/93	35 years
	GARDEN MARKET (Illinois)		IL		—		2,677		4,829		5,181		2,677		10,010		12,687		6,111		1958	7/28/94	35 years
	GOVERNOR PLAZA (Maryland)		MD		—		2,068		4,905		19,744		2,068		24,649		26,717		17,018		1963	10/1/85	35 years
	GRAHAM PARK PLAZA (Virginia)		VA		—		1,237		15,096		17,536		1,169		32,700		33,869		24,764		1971	7/21/83	35 years
	GRATIOT PLAZA (Michigan)		MI		—		525		1,601		17,092		525		18,693		19,218		15,431		1964	3/29/73	25.75 years
	GREENWICH AVENUE (Connecticut)		CT		—		7,484		5,444		1,041		7,484		6,485		13,969		3,590		1968	4/12/95	35 years
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
31-Dec-14
(Dollars in thousands)
COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
										Capitalized		close of period						Depreciation		of	Acquired	depreciation
										Subsequent								and		Construction		in latest
										to								Amortization				income
										Acquisition												statements is
						Land		Building and				Land		Building and		Total						computed
								Improvements						Improvements
HAUPPAUGE (New York)		NY		13,566		8,791		15,262		4,060		8,426		19,687		28,113		9,591		1963	8/6/98	35 years
HERMOSA AVENUE (California)		CA		—		1,116		280		4,485		1,368		4,513		5,881		2,365		1922	9/17/97	35 years
HOLLYWOOD BLVD. (California)		CA		—		8,300		16,920		21,729		8,300		38,649		46,949		10,619		1929/1991	3/22/99 & 6/18/99	35 years
HOUSTON STREET (Texas)		TX		—		14,680		1,976		45,419		14,778		47,297		62,075		27,915		var	1998	35 years
HUNTINGTON (New York)		NY		—		11,713		16,008		16,042		11,713		32,050		43,763		12,121		1962	12/12/88 & 10/26/07	35 years
HUNTINGTON SQUARE (New York)		NY		—		—		10,075		2,307		—		12,382		12,382		1,717		1980/2004-2007	8/16/10	35 years
IDYLWOOD PLAZA (Virginia)		VA		—		4,308		10,026		2,390		4,308		12,416		16,724		7,553		1991	4/15/94	35 years
KINGS COURT (California)		CA		—		—		10,714		894		—		11,608		11,608		7,429		1960	8/24/98	26 years
LANCASTER (Pennsylvania)		PA		4,907		—		2,103		11,441		75		13,469		13,544		7,341		1958	4/24/80	22 years
LANGHORNE SQUARE (Pennsylvania)		PA		—		720		2,974		18,082		720		21,056		21,776		12,997		1966	1/31/85	35 years
LAUREL (Maryland)		MD		—		7,458		22,525		22,974		7,464		45,493		52,957		32,934		1956	8/15/86	35 years
LAWRENCE PARK (Pennsylvania)		PA		25,507		5,723		7,160		19,078		5,734		26,227		31,961		23,109		1972	7/23/80	22 years
LEESBURG PLAZA (Virginia)		VA		—		8,184		10,722		16,729		8,184		27,451		35,635		12,093		1967	9/15/98	35 years
LINDEN SQUARE (Massachusetts)		MA		—		79,382		19,247		48,105		79,269		67,465		146,734		15,329		1960-2008	8/24/06	35 years
MELVILLE MALL (New York)		NY		—		35,622		32,882		1,401		35,622		34,283		69,905		7,968		1974	10/16/06	35 years
MERCER MALL (New Jersey)		NJ		55,741		28,684		48,028		39,012		28,684		87,040		115,724		30,786		1975	10/14/03	25 - 35 years
MONTROSE CROSSING (Maryland)		MD		75,867		48,624		91,819		12,663		48,624		104,482		153,106		12,524		1960s, 1970s, 1996 & 2011	12/27/11, 12/19/13	35 years
MOUNT VERNON/SOUTH VALLEY/7770 RICHMOND HWY. (Virginia)		VA		—		10,068		33,501		38,701		10,230		72,040		82,270		25,865		1966/1972/1987/2001	3/31/03, 3/21/03, & 1/27/06	35 years
TOWN CENTER OF NEW BRITAIN (Pennsylvania)		PA		—		1,282		12,285		1,064		1,341		13,290		14,631		3,752		1969	6/29/06	35 years
NORTH DARTMOUTH (Massachusetts)		MA		—		9,366		—		2		9,366		2		9,368		2		2004	8/24/06
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
31-Dec-14
(Dollars in thousands)
COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
										Capitalized		close of period						Depreciation		of	Acquired	depreciation
										Subsequent								and		Construction		in latest
										to								Amortization				income
										Acquisition												statements is
						Land		Building and				Land		Building and		Total						computed
								Improvements						Improvements
NORTHEAST (Pennsylvania)		PA		—		1,152		10,596		13,116		1,153		23,711		24,864		18,127		1959	8/30/83	35 years
NORTH LAKE COMMONS (Illinois)		IL		—		2,782		8,604		5,184		2,628		13,942		16,570		7,064		1989	4/27/94	35 years
OLD KEENE MILL (Virginia)		VA		—		638		998		4,744		638		5,742		6,380		4,870		1968	6/15/76	33.33 years
OLD TOWN CENTER (California)		CA		—		3,420		2,765		31,637		3,420		34,402		37,822		19,398		1962, 1997-1998	10/22/97	35 years
PAN AM SHOPPING CENTER (Virginia)		VA		—		8,694		12,929		7,178		8,695		20,106		28,801		13,321		1979	2/5/93	35 years
PENTAGON ROW (Virginia)		VA		—		—		2,955		95,525		—		98,480		98,480		39,074		1999 - 2002	1998 & 11/22/10	35 years
PERRING PLAZA (Maryland)		MD		—		2,800		6,461		20,575		2,800		27,036		29,836		20,605		1963	10/1/85	35 years
PIKE & ROSE (Maryland)		MD		—		31,471		10,335		240,995		26,201		256,600		282,801		1,326		1963 & 2012-2014	5/18/82, 10/26/07, & 7/31/12	50 years
PIKE 7 (Virginia)		VA		—		9,709		22,799		3,720		9,653		26,575		36,228		14,025		1968	3/31/97	35 years
PLAZA EL SEGUNDO (California)		CA		180,269		62,127		153,556		36,876		62,127		190,432		252,559		18,186		2006 & 2007	12/30/11, 6/14/13, 7/26/13 & 12/27/13	35 years
QUEEN ANNE PLAZA (Massachusetts)		MA		—		3,319		8,457		6,274		3,319		14,731		18,050		8,433		1967	12/23/94	35 years
QUINCE ORCHARD (Maryland)		MD		—		3,197		7,949		21,878		2,928		30,096		33,024		14,462		1975	4/22/93	35 years
ROCKVILLE TOWN SQUARE (Maryland)		MD		4,508		—		8,092		41,858		—		49,950		49,950		11,727		2005 - 2007	2006 - 2007	50 years
ROLLINGWOOD APTS. (Maryland)		MD		22,130		552		2,246		7,046		572		9,272		9,844		8,189		1960	1/15/71	25 years
SAM'S PARK & SHOP (District of Columbia)		DC		—		4,840		6,319		1,338		4,840		7,657		12,497		4,364		1930	12/1/95	35 years
SANTANA ROW (California)		CA		—		66,682		7,502		619,379		57,574		635,989		693,563		135,085		1999-2006, 2009, 2011, 2014	3/5/97, 7/13/12, 9/6/12, 4/30/13 & 9/23/13	40 - 50 years
SAUGUS PLAZA (Massachusetts)		MA		—		4,383		8,291		2,227		4,383		10,518		14,901		5,436		1976	10/1/96	35 years
SHIRLINGTON (Virginia)		VA		6,491		9,761		14,808		35,364		4,234		55,699		59,933		20,957		1940, 2006-2009	12/21/95	35 years
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
31-Dec-14
(Dollars in thousands)
COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
										Capitalized		close of period						Depreciation		of	Acquired	depreciation
										Subsequent								and		Construction		in latest
										to								Amortization				income
										Acquisition												statements is
						Land		Building and				Land		Building and		Total						computed
								Improvements						Improvements
THE GROVE AT SHREWSBURY (New Jersey)		NJ		59,633		18,016		103,115		406		18,016		103,521		121,537		3,507		1988/1993/2007	1/1/2014 & 10/6/14	35 years
THE SHOPPES AT NOTTINGHAM SQUARE (Maryland)		MD		—		4,441		12,849		148		4,441		12,997		17,438		3,515		2005 - 2006	3/8/07	35 years
THIRD STREET PROMENADE (California)		CA		—		22,645		12,709		42,994		25,125		53,223		78,348		28,315		1888-2000	1996-2000	35 years
TOWER (Virginia)		VA		—		7,170		10,518		3,715		7,280		14,123		21,403		7,396		1953-1960	8/24/98	35 years
TOWER SHOPS (Florida)		FL		—		29,940		43,390		10,594		29,962		53,962		83,924		8,425		1989	1/19/11 & 6/13/14	35 years
TROY (New Jersey)		NJ		—		3,126		5,193		21,653		4,028		25,944		29,972		18,843		1966	7/23/80	22 years
TYSON'S STATION (Virginia)		VA		—		388		453		3,679		475		4,045		4,520		3,277		1954	1/17/78	17 years
WESTGATE CENTER (California)		CA		—		6,319		107,284		28,278		6,319		135,562		141,881		31,731		1960-1966	3/31/04	35 years
WHITE MARSH PLAZA (Maryland)		MD		—		3,478		21,413		248		3,478		21,661		25,139		6,307		1987	3/8/07	35 years
WHITE MARSH OTHER (Maryland)		MD		—		34,281		1,843		402		34,311		2,215		36,526		591		1985	3/8/07	35 years
WILDWOOD (Maryland)		MD		22,420		9,111		1,061		8,354		9,111		9,415		18,526		7,946		1958	5/5/69	33.33 years
WILLOW GROVE (Pennsylvania)		PA		—		1,499		6,643		21,819		1,499		28,462		29,961		23,185		1953	11/20/84	35 years
WILLOW LAWN (Virginia)		VA		—		3,192		7,723		73,143		7,790		76,268		84,058		48,754		1957	12/5/83	35 years
WYNNEWOOD (Pennsylvania)		PA		25,994		8,055		13,759		18,808		8,055		32,567		40,622		18,729		1948	10/29/96	35 years
TOTALS				$	635,345	$	1,116,102	$	1,781,103	$	2,711,793	$	1,102,836	$	4,506,162	$	5,608,998	$	1,467,050
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION - CONTINUED
Three Years Ended December 31, 2014
Reconciliation of Total Cost
(in thousands)
Balance, December 31, 2011	$	4,426,444
Additions during period
Acquisitions	193,131
Improvements	187,990
Deduction during period—disposition and retirements of property	(27,891		)
Balance, December 31, 2012	4,779,674
Additions during period
Acquisitions	76,359
Improvements	329,522
Deduction during period—disposition and retirements of property	(36,092		)
Balance, December 31, 2013	5,149,463
Additions during period
Acquisitions	174,328
Improvements	329,674
Deduction during period—disposition and retirements of property and transfer to joint venture	(44,467		)
Balance, December 31, 2014	$	5,608,998
_____________________
-1	For Federal tax purposes, the aggregate cost basis is approximately $5.1 billion as of December 31, 2014.
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION - CONTINUED
Three Years Ended December 31, 2014
Reconciliation of Accumulated Depreciation and Amortization
(in thousands)
Balance, December 31, 2011	$	1,127,588
Additions during period—depreciation and amortization expense	128,654
Deductions during period—disposition and retirements of property	(31,947		)
Balance, December 31, 2012	1,224,295
Additions during period—depreciation and amortization expense	147,730
Deductions during period—disposition and retirements of property	(21,554		)
Balance, December 31, 2013	1,350,471
Additions during period—depreciation and amortization expense	155,662
Deductions during period—disposition and retirements of property	(39,083		)
Balance, December 31, 2014	$	1,467,050

Schedule_III_Part_II_Summary_o

Schedule III Part II - Summary of Real Estate and Accumulated Depreciation	12 Months Ended
	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Schedule III - Summary of Real Estate and Accumulated Depreciation	FEDERAL REALTY INVESTMENT TRUST
	SCHEDULE III
	SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
	31-Dec-14
	(Dollars in thousands)
	COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
	Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
											Capitalized		close of period						Depreciation		of	Acquired	depreciation
											Subsequent								and		Construction		in latest
											to								Amortization				income
											Acquisition												statements is
							Land		Building and				Land		Building and		Total						computed
									Improvements						Improvements
	150 POST STREET (California)		CA		$	—	$	11,685	$	9,181	$	16,350	$	11,685	$	25,531	$	37,216	$	16,363	1908/1965	10/23/97	35 years
	29TH PLACE (Virginia)		VA		4,917		10,211		18,863		11,222		10,225		30,071		40,296		7,323		1975 - 2001	5/30/07	35 years
	ANDORRA (Pennsylvania)		PA		—		2,432		12,346		10,875		2,432		23,221		25,653		17,090		1953	1/12/88	35 years
	ASSEMBLY ROW/ASSEMBLY SQUARE MARKETPLACE (Massachusetts)		MA		—		93,252		34,196		305,854		93,252		340,050		433,302		21,953		2005, 2012-2014	2005-2013	35 years
	THE AVENUE AT WHITE MARSH (Maryland)		MD		52,705		20,682		72,432		4,514		20,685		76,943		97,628		22,282		1997	3/8/07	35 years
	BALA CYNWYD (Pennsylvania)		PA		—		3,565		14,466		22,187		3,566		36,652		40,218		16,281		1955	9/22/93	35 years
	BARRACKS ROAD (Virginia)		VA		35,985		4,363		16,459		39,643		4,363		56,102		60,465		37,539		1958	12/31/85	35 years
	BETHESDA ROW (Maryland)		MD		—		46,579		35,406		141,226		44,880		178,331		223,211		56,776		1945-2008	12/31/93, 6/2/97, 1/20/06, 9/25/08, 9/30/08, & 12/27/10	35 - 50 years
	BRICK PLAZA (New Jersey)		NJ		26,415		—		24,715		35,770		3,944		56,541		60,485		42,119		1958	12/28/89	35 years
	BRISTOL PLAZA (Connecticut)		CT		—		3,856		15,959		9,602		3,856		25,561		29,417		14,521		1959	9/22/95	35 years
	BROOK 35 (New Jersey)		NJ		11,500		7,128		38,355		573		7,128		38,928		46,056		1,312		1986/2004	1/1/14	35 years
	CHELSEA COMMONS (Massachusetts)		MA		6,790		9,417		19,466		13,825		9,396		33,312		42,708		5,484		1962/1969/2008	8/25/06, 1/30/07, & 7/16/08	35 years
	COLORADO BLVD (California)		CA		—		5,262		4,071		8,787		5,262		12,858		18,120		9,336		1905-1988	12/31/96 & 8/14/98	35 years
	CONGRESSIONAL PLAZA (Maryland)		MD		—		2,793		7,424		69,801		1,020		78,998		80,018		47,425		1965/2003	4/1/65	35 years
	COURTHOUSE CENTER (Maryland)		MD		—		1,750		1,869		1,142		1,750		3,011		4,761		1,589		1975	12/17/97	35 years
	COURTYARD SHOPS (Florida)		FL		—		16,862		21,851		2,025		16,894		23,844		40,738		5,731		1990/1998	9/4/08	35 years
	CROSSROADS (Illinois)		IL		—		4,635		11,611		14,897		4,635		26,508		31,143		14,056		1959	7/19/93	35 years
	FEDERAL REALTY INVESTMENT TRUST
	SCHEDULE III
	SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
	31-Dec-14
	(Dollars in thousands)
	COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
	Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
											Capitalized		close of period						Depreciation		of	Acquired	depreciation
											Subsequent								and		Construction		in latest
											to								Amortization				income
											Acquisition												statements is
							Land		Building and				Land		Building and		Total						computed
									Improvements						Improvements
	CROW CANYON COMMONS (California)		CA		—		27,245		54,575		4,915		27,245		59,490		86,735		15,878		Late 1970's/	12/29/05 & 2/28/07	35 years
																					1998/2006
	DARIEN (Connecticut)		CT		—		29,809		18,302		21		29,809		18,323		48,132		1,134		1920-2009	4/3/13	35 years
	DEDHAM PLAZA (Massachusetts)		MA		—		12,287		12,918		9,834		12,287		22,752		35,039		12,909		1959	12/31/93	35 years
	DEL MAR VILLAGE (Florida)		FL		—		15,624		41,712		2,494		15,587		44,243		59,830		15,971		1982/1994/2007	5/30/08, 7/11/08, & 10/14/14	35 years
	EAST BAY BRIDGE (California)		CA		—		29,079		138,035		1,395		29,079		139,430		168,509		9,604		1994-2001, 2011/2012	12/21/12	35 years
	EASTGATE (North Carolina)		NC		—		1,608		5,775		20,329		1,608		26,104		27,712		17,343		1963	12/18/86	35 years
	ELLISBURG (New Jersey)		NJ		—		4,028		11,309		18,818		4,013		30,142		34,155		17,344		1959	10/16/92	35 years
	ESCONDIDO PROMENADE (California)		CA		—		19,117		15,829		12,118		19,117		27,947		47,064		12,034		1987	12/31/96 & 11/10/10	35 years
	FALLS PLAZA (Virginia)		VA		—		1,798		1,270		9,787		1,819		11,036		12,855		7,607		1960/1962	9/30/67 & 10/05/72	25 years
	FEDERAL PLAZA (Maryland)		MD		—		10,216		17,895		37,699		10,216		55,594		65,810		37,299		1970	6/29/89	35 years
	FINLEY SQUARE (Illinois)		IL		—		9,252		9,544		13,829		9,252		23,373		32,625		16,607		1974	4/27/95	35 years
	FLOURTOWN (Pennsylvania)		PA		—		1,345		3,943		9,010		1,345		12,953		14,298		4,490		1957	4/25/80	35 years
	FRESH MEADOWS (New York)		NY		—		24,625		25,255		30,115		24,633		55,362		79,995		30,687		1946-1949	12/5/97	35 years
	FRIENDSHIP CENTER (District of Columbia)		DC		—		12,696		20,803		3,999		12,696		24,802		37,498		8,889		1998	9/21/01	35 years
	GAITHERSBURG SQUARE (Maryland)		MD		—		7,701		5,271		12,810		5,973		19,809		25,782		15,980		1966	4/22/93	35 years
	GARDEN MARKET (Illinois)		IL		—		2,677		4,829		5,181		2,677		10,010		12,687		6,111		1958	7/28/94	35 years
	GOVERNOR PLAZA (Maryland)		MD		—		2,068		4,905		19,744		2,068		24,649		26,717		17,018		1963	10/1/85	35 years
	GRAHAM PARK PLAZA (Virginia)		VA		—		1,237		15,096		17,536		1,169		32,700		33,869		24,764		1971	7/21/83	35 years
	GRATIOT PLAZA (Michigan)		MI		—		525		1,601		17,092		525		18,693		19,218		15,431		1964	3/29/73	25.75 years
	GREENWICH AVENUE (Connecticut)		CT		—		7,484		5,444		1,041		7,484		6,485		13,969		3,590		1968	4/12/95	35 years
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
31-Dec-14
(Dollars in thousands)
COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
										Capitalized		close of period						Depreciation		of	Acquired	depreciation
										Subsequent								and		Construction		in latest
										to								Amortization				income
										Acquisition												statements is
						Land		Building and				Land		Building and		Total						computed
								Improvements						Improvements
HAUPPAUGE (New York)		NY		13,566		8,791		15,262		4,060		8,426		19,687		28,113		9,591		1963	8/6/98	35 years
HERMOSA AVENUE (California)		CA		—		1,116		280		4,485		1,368		4,513		5,881		2,365		1922	9/17/97	35 years
HOLLYWOOD BLVD. (California)		CA		—		8,300		16,920		21,729		8,300		38,649		46,949		10,619		1929/1991	3/22/99 & 6/18/99	35 years
HOUSTON STREET (Texas)		TX		—		14,680		1,976		45,419		14,778		47,297		62,075		27,915		var	1998	35 years
HUNTINGTON (New York)		NY		—		11,713		16,008		16,042		11,713		32,050		43,763		12,121		1962	12/12/88 & 10/26/07	35 years
HUNTINGTON SQUARE (New York)		NY		—		—		10,075		2,307		—		12,382		12,382		1,717		1980/2004-2007	8/16/10	35 years
IDYLWOOD PLAZA (Virginia)		VA		—		4,308		10,026		2,390		4,308		12,416		16,724		7,553		1991	4/15/94	35 years
KINGS COURT (California)		CA		—		—		10,714		894		—		11,608		11,608		7,429		1960	8/24/98	26 years
LANCASTER (Pennsylvania)		PA		4,907		—		2,103		11,441		75		13,469		13,544		7,341		1958	4/24/80	22 years
LANGHORNE SQUARE (Pennsylvania)		PA		—		720		2,974		18,082		720		21,056		21,776		12,997		1966	1/31/85	35 years
LAUREL (Maryland)		MD		—		7,458		22,525		22,974		7,464		45,493		52,957		32,934		1956	8/15/86	35 years
LAWRENCE PARK (Pennsylvania)		PA		25,507		5,723		7,160		19,078		5,734		26,227		31,961		23,109		1972	7/23/80	22 years
LEESBURG PLAZA (Virginia)		VA		—		8,184		10,722		16,729		8,184		27,451		35,635		12,093		1967	9/15/98	35 years
LINDEN SQUARE (Massachusetts)		MA		—		79,382		19,247		48,105		79,269		67,465		146,734		15,329		1960-2008	8/24/06	35 years
MELVILLE MALL (New York)		NY		—		35,622		32,882		1,401		35,622		34,283		69,905		7,968		1974	10/16/06	35 years
MERCER MALL (New Jersey)		NJ		55,741		28,684		48,028		39,012		28,684		87,040		115,724		30,786		1975	10/14/03	25 - 35 years
MONTROSE CROSSING (Maryland)		MD		75,867		48,624		91,819		12,663		48,624		104,482		153,106		12,524		1960s, 1970s, 1996 & 2011	12/27/11, 12/19/13	35 years
MOUNT VERNON/SOUTH VALLEY/7770 RICHMOND HWY. (Virginia)		VA		—		10,068		33,501		38,701		10,230		72,040		82,270		25,865		1966/1972/1987/2001	3/31/03, 3/21/03, & 1/27/06	35 years
TOWN CENTER OF NEW BRITAIN (Pennsylvania)		PA		—		1,282		12,285		1,064		1,341		13,290		14,631		3,752		1969	6/29/06	35 years
NORTH DARTMOUTH (Massachusetts)		MA		—		9,366		—		2		9,366		2		9,368		2		2004	8/24/06
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
31-Dec-14
(Dollars in thousands)
COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
										Capitalized		close of period						Depreciation		of	Acquired	depreciation
										Subsequent								and		Construction		in latest
										to								Amortization				income
										Acquisition												statements is
						Land		Building and				Land		Building and		Total						computed
								Improvements						Improvements
NORTHEAST (Pennsylvania)		PA		—		1,152		10,596		13,116		1,153		23,711		24,864		18,127		1959	8/30/83	35 years
NORTH LAKE COMMONS (Illinois)		IL		—		2,782		8,604		5,184		2,628		13,942		16,570		7,064		1989	4/27/94	35 years
OLD KEENE MILL (Virginia)		VA		—		638		998		4,744		638		5,742		6,380		4,870		1968	6/15/76	33.33 years
OLD TOWN CENTER (California)		CA		—		3,420		2,765		31,637		3,420		34,402		37,822		19,398		1962, 1997-1998	10/22/97	35 years
PAN AM SHOPPING CENTER (Virginia)		VA		—		8,694		12,929		7,178		8,695		20,106		28,801		13,321		1979	2/5/93	35 years
PENTAGON ROW (Virginia)		VA		—		—		2,955		95,525		—		98,480		98,480		39,074		1999 - 2002	1998 & 11/22/10	35 years
PERRING PLAZA (Maryland)		MD		—		2,800		6,461		20,575		2,800		27,036		29,836		20,605		1963	10/1/85	35 years
PIKE & ROSE (Maryland)		MD		—		31,471		10,335		240,995		26,201		256,600		282,801		1,326		1963 & 2012-2014	5/18/82, 10/26/07, & 7/31/12	50 years
PIKE 7 (Virginia)		VA		—		9,709		22,799		3,720		9,653		26,575		36,228		14,025		1968	3/31/97	35 years
PLAZA EL SEGUNDO (California)		CA		180,269		62,127		153,556		36,876		62,127		190,432		252,559		18,186		2006 & 2007	12/30/11, 6/14/13, 7/26/13 & 12/27/13	35 years
QUEEN ANNE PLAZA (Massachusetts)		MA		—		3,319		8,457		6,274		3,319		14,731		18,050		8,433		1967	12/23/94	35 years
QUINCE ORCHARD (Maryland)		MD		—		3,197		7,949		21,878		2,928		30,096		33,024		14,462		1975	4/22/93	35 years
ROCKVILLE TOWN SQUARE (Maryland)		MD		4,508		—		8,092		41,858		—		49,950		49,950		11,727		2005 - 2007	2006 - 2007	50 years
ROLLINGWOOD APTS. (Maryland)		MD		22,130		552		2,246		7,046		572		9,272		9,844		8,189		1960	1/15/71	25 years
SAM'S PARK & SHOP (District of Columbia)		DC		—		4,840		6,319		1,338		4,840		7,657		12,497		4,364		1930	12/1/95	35 years
SANTANA ROW (California)		CA		—		66,682		7,502		619,379		57,574		635,989		693,563		135,085		1999-2006, 2009, 2011, 2014	3/5/97, 7/13/12, 9/6/12, 4/30/13 & 9/23/13	40 - 50 years
SAUGUS PLAZA (Massachusetts)		MA		—		4,383		8,291		2,227		4,383		10,518		14,901		5,436		1976	10/1/96	35 years
SHIRLINGTON (Virginia)		VA		6,491		9,761		14,808		35,364		4,234		55,699		59,933		20,957		1940, 2006-2009	12/21/95	35 years
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION
31-Dec-14
(Dollars in thousands)
COLUMN A				COLUMN B		COLUMN C				COLUMN D		COLUMN E						COLUMN F		COLUMN G	COLUMN H	COLUMN I
Descriptions				Encumbrance		Initial cost to company				Cost		Gross amount at which carried at						Accumulated		Date	Date	Life on  which
										Capitalized		close of period						Depreciation		of	Acquired	depreciation
										Subsequent								and		Construction		in latest
										to								Amortization				income
										Acquisition												statements is
						Land		Building and				Land		Building and		Total						computed
								Improvements						Improvements
THE GROVE AT SHREWSBURY (New Jersey)		NJ		59,633		18,016		103,115		406		18,016		103,521		121,537		3,507		1988/1993/2007	1/1/2014 & 10/6/14	35 years
THE SHOPPES AT NOTTINGHAM SQUARE (Maryland)		MD		—		4,441		12,849		148		4,441		12,997		17,438		3,515		2005 - 2006	3/8/07	35 years
THIRD STREET PROMENADE (California)		CA		—		22,645		12,709		42,994		25,125		53,223		78,348		28,315		1888-2000	1996-2000	35 years
TOWER (Virginia)		VA		—		7,170		10,518		3,715		7,280		14,123		21,403		7,396		1953-1960	8/24/98	35 years
TOWER SHOPS (Florida)		FL		—		29,940		43,390		10,594		29,962		53,962		83,924		8,425		1989	1/19/11 & 6/13/14	35 years
TROY (New Jersey)		NJ		—		3,126		5,193		21,653		4,028		25,944		29,972		18,843		1966	7/23/80	22 years
TYSON'S STATION (Virginia)		VA		—		388		453		3,679		475		4,045		4,520		3,277		1954	1/17/78	17 years
WESTGATE CENTER (California)		CA		—		6,319		107,284		28,278		6,319		135,562		141,881		31,731		1960-1966	3/31/04	35 years
WHITE MARSH PLAZA (Maryland)		MD		—		3,478		21,413		248		3,478		21,661		25,139		6,307		1987	3/8/07	35 years
WHITE MARSH OTHER (Maryland)		MD		—		34,281		1,843		402		34,311		2,215		36,526		591		1985	3/8/07	35 years
WILDWOOD (Maryland)		MD		22,420		9,111		1,061		8,354		9,111		9,415		18,526		7,946		1958	5/5/69	33.33 years
WILLOW GROVE (Pennsylvania)		PA		—		1,499		6,643		21,819		1,499		28,462		29,961		23,185		1953	11/20/84	35 years
WILLOW LAWN (Virginia)		VA		—		3,192		7,723		73,143		7,790		76,268		84,058		48,754		1957	12/5/83	35 years
WYNNEWOOD (Pennsylvania)		PA		25,994		8,055		13,759		18,808		8,055		32,567		40,622		18,729		1948	10/29/96	35 years
TOTALS				$	635,345	$	1,116,102	$	1,781,103	$	2,711,793	$	1,102,836	$	4,506,162	$	5,608,998	$	1,467,050
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION - CONTINUED
Three Years Ended December 31, 2014
Reconciliation of Total Cost
(in thousands)
Balance, December 31, 2011	$	4,426,444
Additions during period
Acquisitions	193,131
Improvements	187,990
Deduction during period—disposition and retirements of property	(27,891		)
Balance, December 31, 2012	4,779,674
Additions during period
Acquisitions	76,359
Improvements	329,522
Deduction during period—disposition and retirements of property	(36,092		)
Balance, December 31, 2013	5,149,463
Additions during period
Acquisitions	174,328
Improvements	329,674
Deduction during period—disposition and retirements of property and transfer to joint venture	(44,467		)
Balance, December 31, 2014	$	5,608,998
_____________________
-1	For Federal tax purposes, the aggregate cost basis is approximately $5.1 billion as of December 31, 2014.
FEDERAL REALTY INVESTMENT TRUST
SCHEDULE III
SUMMARY OF REAL ESTATE AND ACCUMULATED DEPRECIATION - CONTINUED
Three Years Ended December 31, 2014
Reconciliation of Accumulated Depreciation and Amortization
(in thousands)
Balance, December 31, 2011	$	1,127,588
Additions during period—depreciation and amortization expense	128,654
Deductions during period—disposition and retirements of property	(31,947		)
Balance, December 31, 2012	1,224,295
Additions during period—depreciation and amortization expense	147,730
Deductions during period—disposition and retirements of property	(21,554		)
Balance, December 31, 2013	1,350,471
Additions during period—depreciation and amortization expense	155,662
Deductions during period—disposition and retirements of property	(39,083		)
Balance, December 31, 2014	$	1,467,050

Schedule_IV_Mortgage_Loans_on_

Schedule IV - Mortgage Loans on Real Estate

12 Months Ended

Dec. 31, 2014

Mortgage Loans on Real Estate [Abstract]

Schedule IV - Mortgage Loans on Real Estate

FEDERAL REALTY INVESTMENT TRUST

SCHEDULE IV

MORTGAGE LOANS ON REAL ESTATE

Year Ended December 31, 2014

(Dollars in thousands)

Column A

Column B

Column C

Column D

Column E

Column F

Column G

Column H

Description of Lien

Interest Rate

Maturity Date

Periodic Payment

Prior

Face Amount

Carrying

Principal

Terms

Liens

of Mortgages

Amount

Amount

of Mortgages(1)

of Loans

Subject to

delinquent

Principal

or Interest

Mortgage on

8% or 10%

May-21

Interest only

$

—

$

20,286

$

20,286

-2

$

—

retail buildings in Philadelphia, PA

based on

monthly; balloon payment due at maturity

timing of

draws, plus

participation

Mortgage on retail buildings in Philadelphia, PA

10% plus participation

May-21

Interest only monthly;

—

9,250

9,250

—

balloon payment due

at maturity

Second Mortgage

9%

August 2016

Principal and interest; balloon payment due at maturity(3)

34,000

-4

10,691

9,737

—

on hotel building in San Jose, CA

Mortgage on retail building in Norwalk, CT

7%

Jun-15

Interest only; balloon payment due at maturity

—

11,715

11,715

—

$

34,000

$

51,942

$

50,988

$

—

_____________________

-1

For Federal tax purposes, the aggregate tax basis is approximately $51.9 million as of December 31, 2014.

-2

This mortgage is available for up to $25.0 million.

-3

This note was amended on August 4, 2006. The amended note decreased the interest from 14% to 9% per annum, and requires monthly payments of principal and interest based on 15-year amortization schedule.

-4

We do not hold the first mortgage loan on this property. Accordingly, the amount of the prior lien at December 31, 2014 is estimated.

FEDERAL REALTY INVESTMENT TRUST

SCHEDULE IV

MORTGAGE LOANS ON REAL ESTATE - CONTINUED

Three Years Ended December 31, 2014

Reconciliation of Carrying Amount

(in thousands)

Balance, December 31, 2011

$

55,967

Additions during period:

Issuance of loans

70

Deductions during period:

Collection and satisfaction of loans

(1,161

)

Amortization of discount

772

Balance, December 31, 2012

55,648

Deductions during period:

Collection and satisfaction of loans

(1,057

)

Amortization of discount

564

Balance, December 31, 2013

55,155

Deductions during period:

Collection and satisfaction of loans

(4,778

)

Amortization of discount

611

Balance, December 31, 2014

$

50,988

Summary_Of_Significant_Account1

Summary Of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation
	Our consolidated financial statements include the accounts of the Trust, its corporate subsidiaries, and all entities in which the Trust has a controlling interest or has been determined to be the primary beneficiary of a variable interest entity (“VIE”). The equity interests of other investors are reflected as noncontrolling interests or redeemable noncontrolling interests. All significant intercompany transactions and balances are eliminated in consolidation. We account for our interests in joint ventures, which we do not control, using the equity method of accounting.
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America, referred to as “GAAP,” requires management to make estimates and assumptions that in certain circumstances affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities, and revenues and expenses. These estimates are prepared using management’s best judgment, after considering past, current and expected events and economic conditions. Actual results could differ from these estimates.
Revenue Recognition and Accounts Receivable	Revenue Recognition and Accounts Receivable
	Our leases with tenants are classified as operating leases. Substantially all such leases contain fixed escalations which occur at specified times during the term of the lease. Base rents are recognized on a straight-line basis from when the tenant controls the space through the term of the related lease, net of valuation adjustments, based on management’s assessment of credit, collection and other business risk. Percentage rents, which represent additional rents based upon the level of sales achieved by certain tenants, are recognized at the end of the lease year or earlier if we have determined the required sales level is achieved and the percentage rents are collectible. Real estate tax and other cost reimbursements are recognized on an accrual basis over the periods in which the related expenditures are incurred. For a tenant to terminate its lease agreement prior to the end of the agreed term, we may require that they pay a fee to cancel the lease agreement. Lease termination fees for which the tenant has relinquished control of the space are generally recognized on the termination date. When a lease is terminated early but the tenant continues to control the space under a modified lease agreement, the lease termination fee is generally recognized evenly over the remaining term of the modified lease agreement.
	We make estimates of the collectability of our accounts receivable related to minimum rents, straight-line rents, expense reimbursements and other revenue. Accounts receivable is carried net of this allowance for doubtful accounts. Our determination as to the collectability of accounts receivable and correspondingly, the adequacy of this allowance, is based primarily upon evaluations of individual receivables, current economic conditions, historical experience and other relevant factors. The allowance for doubtful accounts is increased or decreased through bad debt expense. Accounts receivable are written-off when they are deemed to be uncollectible and we are no longer actively pursuing collection. At December 31, 2014 and 2013, our allowance for doubtful accounts was $12.4 million and $12.7 million, respectively.
	In some cases, primarily relating to straight-line rents, the collection of accounts receivable extends beyond one year. Our experience relative to unbilled straight-line rents is that a portion of the amounts otherwise recognizable as revenue is never billed to or collected from tenants due to early lease terminations, lease modifications, bankruptcies and other factors. Accordingly, the extended collection period for straight-line rents along with our evaluation of tenant credit risk may result in the nonrecognition of a portion of straight-line rental income until the collection of such income is reasonably assured. If our evaluation of tenant credit risk changes indicating more straight-line revenue is reasonably collectible than previously estimated and realized, the additional straight-line rental income is recognized as revenue. If our evaluation of tenant credit risk changes indicating a portion of realized straight-line rental income is no longer collectible, a reserve and bad debt expense is recorded. At December 31, 2014 and 2013, accounts receivable include approximately $66.1 million and $60.6 million, respectively, related to straight-line rents.
Real Estate	Real Estate
	Land, buildings and improvements are recorded at cost. Depreciation is computed using the straight-line method. Estimated useful lives range generally from 35 years to a maximum of 50 years on buildings and major improvements. Minor improvements, furniture and equipment are capitalized and depreciated over useful lives ranging from 2 to 20 years. Maintenance and repairs that do not improve or extend the useful lives of the related assets are charged to operations as incurred. Tenant improvements are capitalized and depreciated over the life of the related lease or their estimated useful life, whichever is shorter. If a tenant vacates its space prior to contractual termination of its lease, the undepreciated balance of any tenant improvements are written off if they are replaced or have no future value. In 2014, 2013 and 2012, real estate depreciation expense was $155.7 million, $147.7 million and $128.7 million, respectively, including amounts from discontinued operations and assets under capital lease obligations.
	Sales of real estate are recognized only when sufficient down payments have been obtained, possession and other attributes of ownership have been transferred to the buyer and we have no significant continuing involvement. The application of these criteria can be complex and requires us to make assumptions. We believe these criteria were met for all real estate sold during the periods presented.
	Our methodology of allocating the cost of acquisitions to assets acquired and liabilities assumed is based on estimated fair values, replacement cost and/or appraised values. When we acquire operating real estate properties, the purchase price is allocated to land, building, improvements, leasing costs, intangibles such as in-place leases, assumed debt, if any, and to current assets and liabilities acquired, if any. The value allocated to in-place leases is amortized over the related lease term and reflected as rental income in the consolidated statements of comprehensive income. We consider qualitative and quantitative factors in evaluating the likelihood of a tenant exercising a below market renewal option and include such renewal options in the calculation of in-place lease value when we consider these to be bargain renewal options. If the value of below market lease intangibles includes renewal option periods, we include such renewal periods in the amortization period utilized. If a tenant vacates its space prior to contractual termination of its lease, the unamortized balance of any in-place lease value is written off to rental income.
	Transaction costs related to the acquisition of a business, such as broker fees, transfer taxes, legal, accounting, valuation, and other professional and consulting fees, are expensed as incurred and included in “general and administrative expenses” in our consolidated statements of comprehensive income. The acquisition of an operating shopping center typically qualifies as a business. For asset acquisitions not meeting the definition of a business, transaction costs are capitalized as part of the acquisition cost.
	When applicable, as lessee, we classify our leases of land and building as operating or capital leases. We are required to use judgment and make estimates in determining the lease term, the estimated economic life of the property and the interest rate to be used in determining whether or not the lease meets the qualification of a capital lease and is recorded as an asset.
	We capitalize certain costs related to the development and redevelopment of real estate including pre-construction costs, real estate taxes, insurance, construction costs and salaries and related costs of personnel directly involved. Additionally, we capitalize interest costs related to development and redevelopment activities. Capitalization of these costs begin when the activities and related expenditures commence and cease when the project is substantially complete and ready for its intended use at which time the project is placed in service and depreciation commences. Additionally, we make estimates as to the probability of certain development and redevelopment projects being completed. If we determine the development or redevelopment is no longer probable of completion, we expense all capitalized costs which are not recoverable.
	We review for impairment on a property by property basis. Impairment is recognized on properties held for use when the expected undiscounted cash flows for a property are less than its carrying amount at which time the property is written-down to fair value. Properties held for sale are recorded at the lower of the carrying amount or the expected sales price less costs to sell. Effective January 1, 2014, we adopted ASU 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity,” as further discussed in "Recently Adopted Accounting Pronouncements."  Prior to January 1, 2014, the sale or disposal of a “component of an entity” was treated as discontinued operations. The operating properties sold by us prior to January 1, 2014 typically met the definition of a component of an entity and as such the revenues and expenses associated with sold properties were reclassified to discontinued operations for all periods presented.
Cash and Cash Equivalents	Cash and Cash Equivalents
	We define cash and cash equivalents as cash on hand, demand deposits with financial institutions and short term liquid investments with an initial maturity, when purchased, under three months. Cash balances in individual banks may exceed the federally insured limit by the Federal Deposit Insurance Corporation (the “FDIC”). At December 31, 2014, we had $47.7 million in excess of the FDIC insured limit.
Prepaid Expenses and Other Assets	Prepaid Expenses and Other Assets
	Prepaid expenses and other assets consist primarily of lease costs, prepaid property taxes and acquired above market leases. Capitalized lease costs are direct costs incurred which were essential to originate a lease and would not have been incurred had the leasing transaction not taken place and include third party commissions and salaries and related costs of personnel directly related to time spent obtaining a lease. Capitalized lease costs are amortized over the life of the related lease. If a tenant vacates its space prior to the contractual termination of its lease, the unamortized balance of any previously capitalized lease costs are written off.
Debt Issuance Costs	Debt Issuance Costs
	Costs related to the issuance of debt instruments are capitalized and are amortized as interest expense over the estimated life of the related issue using the straight-line method which approximates the effective interest method. If a debt instrument is paid off prior to its original maturity date, the unamortized balance of debt issuance costs are written off to interest expense or, if significant, included in “early extinguishment of debt.”
Derivative Instruments	Derivative Instruments
	At times, we may use derivative instruments to manage exposure to variable interest rate risk. We generally enter into interest rate swaps to manage our exposure to variable interest rate risk and treasury locks to manage the risk of interest rates rising prior to the issuance of debt. We enter into derivative instruments that qualify as cash flow hedges and do not enter into derivative instruments for speculative purposes.
	The interest rate swaps associated with our cash flow hedges are recorded at fair value on a recurring basis. We assess effectiveness of our cash flow hedges both at inception and on an ongoing basis. The effective portion of changes in fair value of the interest rate swaps associated with our cash flow hedges is recorded in accumulated other comprehensive loss and is subsequently reclassified into interest expense as interest is incurred on the related variable rate debt; within the next twelve months, we expect to reclassify an estimated $3.8 million as an increase to interest expense. Our cash flow hedges become ineffective if critical terms of the hedging instrument and the debt instrument do not perfectly match such as notional amounts, settlement dates, reset dates, calculation period and LIBOR rate. In addition, we evaluate the default risk of the counterparty by monitoring the credit worthiness of the counterparty. When ineffectiveness exists, the ineffective portion of changes in fair value of the interest rate swaps associated with our cash flow hedges is recognized in earnings in the period affected. Hedge ineffectiveness did not impact earnings in 2014, 2013 or 2012, and we do not anticipate it will have a significant effect in the future.
	See Note 8 for additional disclosures relating to our two existing interest rate swap agreements.
Mortgage Notes Receivable	Mortgage Notes Receivable
	We have made certain mortgage loans that, because of their nature, qualify as loan receivables. At the time the loans were made, we did not intend for the arrangement to be anything other than a financing and did not contemplate a real estate investment. We evaluate each investment to determine whether the loan arrangement qualifies as a loan, joint venture or real estate investment and the appropriate accounting thereon. Such determination affects our balance sheet classification of these investments and the recognition of interest income derived therefrom. On some of the loans we receive additional interest, however, we never receive in excess of 50% of the residual profit in the project, and because the borrower has either a substantial investment in the project or has guaranteed all or a portion of our loan (or a combination thereof), the loans qualify for loan accounting. The amounts under these arrangements are presented as mortgage notes receivable at December 31, 2014 and 2013.
	Mortgage notes receivable are recorded at cost, net of any valuation adjustments. Interest income is accrued as earned. Mortgage notes receivable are considered past due based on the contractual terms of the note agreement. On a quarterly basis, we evaluate the collectability of each mortgage note receivable based on various factors which may include payment history, expected fair value of the collateral securing the loan, internal and external credit information and/or economic trends. A loan is considered impaired when, based upon current information and events, it is probable that we will be unable to collect all amounts due under the existing contractual terms. When a loan is considered impaired, the amount of the loss accrual is calculated by comparing the carrying amount of the mortgage note receivable to the present value of expected future cash flows. Since all of our loans are collateralized by either a first or second mortgage, the loans have risk characteristics similar to the risks in owning commercial real estate.
Share Based Compensation	Share Based Compensation
	We grant share based compensation awards to employees and trustees typically in the form of restricted common shares, commons shares, and options. We measure stock based compensation expense based on the grant date fair value of the award and recognize the expense ratably over the requisite service period, which is typically the vesting period. See Note 15 for further discussion regarding our share based compensation plans and policies.
Variable Interest Entities	Variable Interest Entities
	Certain entities that do not have sufficient equity at risk for the entity to finance its activities without additional subordinated financial support from other parties or in which equity investors do not have the characteristics of a controlling financial interest qualify as VIEs. VIEs are required to be consolidated by their primary beneficiary. The primary beneficiary of a VIE has both the power to direct the activities that most significantly impact economic performance of the VIE and the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE.
	We have evaluated our investments in certain joint ventures including our real estate partnership with affiliates of a discretionary fund created and advised by ING Clarion Partners and determined that these joint ventures do not meet the requirements of a variable interest entity and, therefore, consolidation of these ventures is not required. These investments are accounted for using the equity method. We have also evaluated our mortgage loans receivable and determined that entities obligated under the mortgage loans are not VIEs for all periods presented. Our investment balances from our real estate partnership and mortgage notes receivable are presented separately in our consolidated balance sheets.
	On October 16, 2006, we acquired the leasehold interest in Melville Mall under a 20 year master lease. Additionally, we loaned the owner of Melville Mall $34.2 million secured by a second mortgage on the property. On June 3, 2014, we repaid the third party mortgage loan as further discussed in Note 7, and effectively became the first mortgage lender on the property. We have an option to purchase the shopping center on or after October 16, 2021 for a price of $5.0 million plus the assumption/repayment of the first and second mortgages. If we fail to exercise our purchase option, the owner of Melville Mall has a put option which would require us to purchase Melville Mall in 2023 for $5.0 million and the assumption of the owner’s mortgage debt. We have determined that this property is held in a variable interest entity for which we are the primary beneficiary. Accordingly, beginning October 16, 2006, we consolidated this property and its operations. As of December 31, 2013, $20.7 million is included in mortgages payable (net of unamortized discount) for the mortgage loan secured by Melville Mall, however, the loan was not our legal obligation. At December 31, 2014 and 2013, net real estate assets related to Melville Mall included in our consolidated balance sheets are approximately $61.9 million and $62.6 million, respectively.
	In conjunction with the acquisition of Darien Shopping Center, we entered into a Reverse Section 1031 like-kind exchange agreement with a third party intermediary. The exchange agreement was for a maximum of 180 days and allowed us, for tax purposes, to defer gains on sale of other properties sold within this period. From April 3, 2013 to September 10, 2013, the third party intermediary was the legal owner of the property, although we controlled the activities that most significantly impacted the property, retained all of the economic benefits and risks associated with the property, and were the primary beneficiary. Accordingly, effective April 3, 2013, we consolidated Darien Shopping Center and its operations even during the period it was held by a third party intermediary.
	We determined the joint venture that owns Plaza El Segundo is a variable interest entity for which we are the primary beneficiary.  We are the managing member and own 48.2% of the entity.  We control the significant operating decisions, consequently having the power to direct the activities that most significantly impact economic performance of the VIE, and have the obligation to absorb the majority of the losses and receive the majority of the benefits.  Therefore, the entity is consolidated in our financial statements as of December 30, 2011.  As of December 31, 2014 and 2013, net real estate assets related to Plaza El Segundo included in our consolidated balance sheets are approximately $178.1 million and $183.4 million, respectively, and mortgages payable (net of unamortized premium) of $180.3 million and $182.1 million, respectively.  Plaza El Segundo's creditors do not have recourse to our general credit.  Our maximum exposure to loss is approximately $19.5 million.
	As further discussed in Note 3, we have entered into an agreement to acquire the interest of one of the noncontrolling interest holders in The Grove at Shrewsbury in 2015. The entity that holds this interest is a variable interest entity for which we are the primary beneficiary. As of December 31, 2014, net real estate assets related to this entity's interest in The Grove at Shrewsbury included in our consolidated balance sheet are approximately $15.7 million and a mortgage payable (net of unamortized premium) of $7.4 million.
Redeemable Noncontrolling Interests	Redeemable Noncontrolling Interests
	We have certain noncontrolling interests that are redeemable for cash upon the occurrence of an event that is not solely in our control and therefore are classified outside of permanent equity. We adjust the carrying amounts of these noncontrolling interests that are currently redeemable to redemption value at the balance sheet date. Adjustments to the carrying amount to reflect changes in redemption value are recorded as adjustments to additional paid-in capital in shareholders' equity. These amounts are classified within the mezzanine section of the consolidated balance sheets.
	The following table provides a rollforward of the redeemable noncontrolling interests:
		Year Ended
		December 31,
		2014			2013
		(In thousands)
	Beginning balance	$	104,425		$	94,420
	Net income	3,452			2,887
	Distributions & Redemptions	(3,714		)	(3,822		)
	Contributions	5,858			1,083
	Adjustment to redeemable noncontrolling interests	9,032			9,857
	Ending balance	$	119,053		$	104,425
Income Taxes	Income Taxes
	We operate in a manner intended to enable us to qualify as a REIT for federal income tax purposes. A REIT that distributes at least 90% of its taxable income to its shareholders each year and meets certain other conditions is not taxed on that portion of its taxable income which is distributed to its shareholders. Therefore, federal income taxes on our taxable income have been and are generally expected to be immaterial. We are obligated to pay state taxes, generally consisting of franchise or gross receipts taxes in certain states. Such state taxes also have not been material.
	We have elected to treat certain of our subsidiaries as taxable REIT subsidiaries, which we refer to as a TRS. In general, a TRS may engage in any real estate business and certain non-real estate businesses, subject to certain limitations under the Internal Revenue Code of 1986, as amended (the “Code”). A TRS is subject to federal and state income taxes. Our TRS activities have not been material.
	With few exceptions, we are no longer subject to U.S. federal, state, and local tax examinations by tax authorities for years before 2010. As of December 31, 2014 and 2013, we had no material unrecognized tax benefits. While we currently have no material unrecognized tax benefits, as a policy, we recognize penalties and interest accrued related to unrecognized tax benefits as income tax expense.
Segment Information	Segment Information
	Our primary business is the ownership, management, and redevelopment of retail and mixed-use properties. We review operating and financial information for each property on an individual basis and therefore, each property represents an individual operating segment. We evaluate financial performance using property operating income, which consists of rental income, other property income and mortgage interest income, less rental expenses and real estate taxes. No individual property constitutes more than 10% of our revenues or property operating income and we have no operations outside of the United States of America. Therefore, we have aggregated our properties into one reportable segment as the properties share similar long-term economic characteristics and have other similarities including the fact that they are operated using consistent business strategies, are typically located in major metropolitan areas, and have similar tenant mixes.
Recently Adopted and Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements
	In April 2014, the FASB issued ASU 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity.” ASU 2014-08 amends the definition of a discontinued operation to include only the disposal of a component of an entity that represents a strategic shift that has or will have a major impact on an entity’s operations and financial results. The standard also requires additional disclosures about discontinued operations as well as disposal transactions that do not meet the discontinued operations criteria. The standard is applicable prospectively for all disposals initially classified as held for sale in periods after adoption. We adopted the standard effective January 1, 2014, and there was no impact to the current period financial statements.  In future periods, the adoption will result in most individual property disposals not qualifying for discontinued operations presentation and thus, the results of those disposals will remain in “income from continuing operations.”  Properties sold prior to January 1, 2014, are not subject to ASU 2014-08 and therefore, continue to be classified as discontinued operations using the previous definition.
	Recently Issued Accounting Pronouncements
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers." ASU 2014-09 supersedes nearly all existing revenue recognition guidance under GAAP and replaces it with a core revenue recognition principle, that an entity will recognize revenue when it transfers control of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services, and creates a five-step model for revenue recognition in accordance with this principle. ASU 2014-09 also requires new disclosures in both interim and annual reporting periods. The guidance in ASU 2014-09 does not apply to contracts within the scope of ASC 840, Leases. ASU 2014-09 will be effective for us in the first quarter of 2017 and allows for either full retrospective or modified retrospective adoption. We are currently assessing the impact of this standard to our consolidated financial statements.
	In August 2014, the FASB issued ASU 2014-15, “Disclosures of Uncertainties about an Entity’s Ability to Continue as a Going Concern.”  ASU 2014-15 provides guidance regarding management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and if such doubt exists, requires specific disclosures.  ASU 2014-15 is effective for us in the first quarter of 2017 and is not expected to have a significant impact on our consolidated financial statements.
	In January 2015, the FASB issued ASU 2015-01, "Income Statement - Extraordinary and Unusual Items." ASU 2015-01 eliminates the concept, and related presentation and disclosure requirements, of an extraordinary item. The presentation and disclosure guidance for items that are unusual in nature or occur infrequently will be retained and will be expanded to include those items that are both unusual in nature and infrequently occurring. ASU 2015-01 is effective for us in the first quarter of 2016 and is not expected to have a significant impact on our consolidated financial statements.

Summary_Of_Significant_Account2

Summary Of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Rollforward table of the redeemable noncontrolling interest	The following table provides a rollforward of the redeemable noncontrolling interests:
		Year Ended
		December 31,
		2014			2013
		(In thousands)
	Beginning balance	$	104,425		$	94,420
	Net income	3,452			2,887
	Distributions & Redemptions	(3,714		)	(3,822		)
	Contributions	5,858			1,083
	Adjustment to redeemable noncontrolling interests	9,032			9,857
	Ending balance	$	119,053		$	104,425
Schedule of supplemental disclosures related to the Consolidated Statements Of Cash Flows	The following table provides supplemental disclosures related to the Consolidated Statements of Cash Flows:
		Year Ended December 31,
		2014			2013			2012
		(In thousands)
	SUPPLEMENTAL DISCLOSURES:
	Total interest costs incurred	$	114,912		$	121,158		$	123,441
	Interest capitalized	(20,971		)	(16,181		)	(10,105		)
	Interest expense	$	93,941		$	104,977		$	113,336
	Cash paid for interest, net of amounts capitalized	$	100,011		$	120,934		$	114,419
	Cash paid (refunded) for income taxes	$	278		$	410		$	(1,151	)
	NON-CASH INVESTING AND FINANCING TRANSACTIONS:
	Mortgage loans assumed with acquisition	$	68,282		$	—		$	67,615
	DownREIT operating partnership units issued with acquisition	$	65,348		$	—		$	—
	Mortgage loans refinanced	$	64,205		$	—		$	—
	Repayment of note payable with public funding/related construction-in-progress offset	$	10,000		$	—		$	—
	Shares issued under dividend reinvestment plan	$	1,855		$	1,779		$	1,864

Real_Estate_Tables

Real Estate (Tables)	12 Months Ended
	Dec. 31, 2014
Real Estate [Abstract]
Summary of real estate investments and related encumbrances	A summary of our real estate investments and related encumbrances is as follows:
		Cost		Accumulated			Encumbrances
				Depreciation and
				Amortization
		(In thousands)
	December 31, 2014
	Retail and mixed-use properties	$	5,478,085	$	(1,423,682	)	$	541,568
	Retail properties under capital leases	121,069		(35,179		)	71,647
	Residential	9,844		(8,189		)	22,130
		$	5,608,998	$	(1,467,050	)	$	635,345
	December 31, 2013
	Retail and mixed-use properties	$	5,024,800	$	(1,310,791	)	$	565,935
	Retail properties under capital leases	115,028		(31,955		)	71,671
	Residential	9,635		(7,725		)	22,521
		$	5,149,463	$	(1,350,471	)	$	660,127

Real_Estate_Partnerships_Table

Real Estate Partnerships (Tables)	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Summarized operating results and the financial position of Partnership	The following tables provide summarized operating results and the financial position of the Partnership:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	OPERATING RESULTS
	Revenue	$	18,329	$	19,209	$	19,051
	Expenses
	Other operating expenses	5,948		5,999		5,234
	Depreciation and amortization	5,678		5,506		5,508
	Interest expense	2,759		3,363		3,376
	Total expenses	14,385		14,868		14,118
	Net income before gain on sale of real estate	3,944		4,341		4,933
	Gain on sale of real estate	14,507		—		—
	Net income	$	18,451	$	4,341	$	4,933
	Our share of net income from real estate partnership before gain on sale of real estate	$	1,423	$	1,498	$	1,815
	Our share of gain on sale of real estate	$	4,401	$	—	$	—
		December 31,
		2014		2013
		(In thousands)
	BALANCE SHEETS
	Real estate, net	$	149,203	$	170,867
	Cash	2,864		2,210
	Other assets	5,346		5,668
	Total assets	$	157,413	$	178,745
	Mortgages payable	$	34,385	$	56,922
	Other liabilities	3,673		4,100
	Partners’ capital	119,355		117,723
	Total liabilities and partners’ capital	$	157,413	$	178,745
	Our share of unconsolidated debt	$	10,316	$	17,077
	Our investment in real estate partnership	$	32,367	$	32,264

Acquired_InPlace_Leases_Tables

Acquired In-Place Leases (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization for acquired in-place leases during the next five years and thereafter	The amortization for acquired in-place leases during the next five years and thereafter, assuming no early lease terminations, is as follows:
		Above Market		Below Market
		Leases		Leases
		(In thousands)
	Year ending December 31,
	2015	$	2,892	$	5,327
	2016	2,476		4,898
	2017	1,784		4,653
	2018	1,275		3,706
	2019	923		3,610
	Thereafter	4,012		50,632
		$	13,362	$	72,826

Debt_Tables

Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Instruments [Abstract]
Summary of total debt outstanding	The following is a summary of our total debt outstanding as of December 31, 2014 and 2013:
				Principal Balance as of December 31,							Stated Interest Rate as of
	Description of Debt			2014				2013			December 31, 2014		Stated Maturity Date
	Mortgages payable			(Dollars in thousands)
	Melville Mall			$	—			$	20,705		5.25	%	September 1, 2014
	THE AVENUE at White Marsh			—				54,112			5.46	%	January 1, 2015
	Barracks Road			35,985				37,069			7.95	%	November 1, 2015
	Hauppauge			13,566				13,974			7.95	%	November 1, 2015
	Lawrence Park			25,507				26,275			7.95	%	November 1, 2015
	Wildwood			22,420				23,095			7.95	%	November 1, 2015
	Wynnewood			25,994				26,777			7.95	%	November 1, 2015
	Brick Plaza			26,415				27,254			7.42	%	November 1, 2015
	East Bay Bridge			—				61,980			5.13	%	March 1, 2016
	Plaza El Segundo			175,000				175,000			6.33	%	August 5, 2017
	The Grove at Shrewsbury (East)			44,519				—			5.82	%	October 1, 2017
	The Grove at Shrewsbury (West)			11,242				—			6.38	%	March 1, 2018
	Rollingwood Apartments			22,130				22,521			5.54	%	May 1, 2019
	29th Place			4,941				5,119			5.91	%	January 31, 2021
	THE AVENUE at White Marsh			52,705				—			3.35	%	January 1, 2022
	Montrose Crossing			75,867				77,341			4.2	%	January 10, 2022
	Brook 35			11,500				—			4.65	%	July 1, 2029
	Chelsea			7,074				7,269			5.36	%	January 15, 2031
	Subtotal			554,865				578,491
	Net unamortized premium			8,833				9,965
	Total mortgages payable			563,698				588,456
	Notes payable
	Escondido (municipal bonds)			9,400				9,400			0.06	%	October 1, 2016
	Revolving credit facility			—				—			LIBOR + 0.90%		April 21, 2017
	Term loan			275,000				275,000			LIBOR + 0.90%		November 21, 2018
	Various			6,119				16,422			11.31	%	Various through 2028
	Total notes payable			290,519				300,822
	Senior notes and debentures
	5.65% notes			—				125,000			5.65	%	June 1, 2016
	6.20% notes			200,000				200,000			6.2	%	January 15, 2017
	5.90% notes			150,000				150,000			5.9	%	April 1, 2020
	3.00% notes			250,000				250,000			3	%	August 1, 2022
	2.75% notes			275,000				275,000			2.75	%	June 1, 2023
	3.95% notes			300,000				300,000			3.95	%	January 15, 2024
	7.48% debentures			29,200				29,200			7.48	%	August 15, 2026
	6.82% medium term notes			40,000				40,000			6.82	%	August 1, 2027
	4.50% notes			250,000				—			4.5	%	December 1, 2044
	Subtotal			1,494,200				1,369,200
	Net unamortized discount			(10,387		)		(8,287		)
	Total senior notes and debentures			1,483,813				1,360,913
	Capital lease obligations
	Various			71,647				71,671			Various		Various through 2106
	Total debt and capital lease obligations			$	2,409,677			$	2,321,862
Conctractual terms of secured mortgage loans assumed in acquisition	The mortgage loans are secured by the individual properties with the following contractual terms:
		Principal				Stated Interest Rate			Maturity Date
		(In millions)
	Brook 35 Plaza	$	11.5			5.46	%		July 1, 2014
	The Grove at Shrewsbury (East)	$	45.4			5.82	%		October 1, 2017
	The Grove at Shrewsbury (West)	$	11.4			6.38	%		March 1, 2018
Schedule of loans or debt securities refinanced or issued during the period
	During 2014, we refinanced or issued the following loans or debt securities:
			Amount				Stated Interest Rate			Refinance/Issuance Date	Maturity Date
			(In millions)
	Brook 35 Plaza Mortgage Loan	Refinance	$	11.5			4.65	%		June 2, 2014	July 1, 2029
	4.50% Senior Notes (1)	Issuance	$	250			4.5	%		November 14, 2014	December 1, 2044
	THE AVENUE at White Marsh Mortgage Loan	Refinance	$	52.7			3.35	%		December 15, 2014	January 1, 2022
	(1) The net proceeds from this note offering after issuance discounts, underwriting fees and other costs were approximately $244.6 million.
Schedule of repaid loans or debt securities
	During 2014, we fully repaid or redeemed the following loans or debt securities:
			Payoff Amount				Repayment Date		Maturity Date
			(In millions)
	Melville Mall Mortgage Loan		$	20.3			June 3, 2014		September 1, 2014
	East Bay Bridge Mortgage Loan (1)		$	61			December 10, 2014		March 1, 2016
	5.65% Senior Notes (2)		$	125			December 12, 2014		June 1, 2016
	(1) The total amount due at payoff of $64.0 million included a prepayment premium of $3.0 million and accrued but unpaid interest of $0.1 million. The prepayment premium is included in "early extinguishment of debt" in 2014.
	(2) The redemption price of $134.5 million included a make-whole premium of approximately $9.2 million and accrued but unpaid interest of $0.2 million. The make-whole premium is included in "early extinguishment of debt" in 2014.
Schedule of principal payments on mortgages payable, notes payable, senior notes and debentures	Scheduled principal payments on mortgages payable, notes payable, senior notes and debentures as of December 31, 2014 are as follows:
		Mortgages					Notes				Senior Notes and			Total
		Payable					Payable				Debentures			Principal
		(In thousands)
	Year ending December 31,
	2015	$	153,395				$	369			$	—		$	153,764
	2016	3,774					9,806				—			13,580
	2017	220,438					451			-1	200,000			420,889
	2018	13,326					275,500				—			288,826
	2019	22,731					553				—			23,284
	Thereafter	141,201					3,840				1,294,200			1,439,241
		$	554,865				$	290,519			$	1,494,200		$	2,339,584	-2
	_____________________
	-1	Our $600.0 million revolving credit facility matures on April 21, 2017, subject to a one-year extension at our option. As of December 31, 2014, there was no balance outstanding under this credit facility.
	-2	The total debt maturities differ from the total reported on the consolidated balance sheet as of December 31, 2014 due to the unamortized discount or premium on certain senior notes and mortgages payable.
Schedule of future minimum lease payments and their present value for property under capital leases	Future minimum lease payments and their present value for property under capital leases as of December 31, 2014, are as follows:
		(In thousands)
	Year ending December 31,
	2015	$	5,787
	2016	5,788
	2017	5,797
	2018	5,800
	2019	5,800
	Thereafter	160,210
		189,182
	Less amount representing interest	(117,535		)
	Present value	$	71,647

Fair_Value_Of_Financial_Instru1

Fair Value Of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Summary of carrying amount and fair value of financial instruments	A summary of the carrying amount and fair value of our mortgages payable, notes payable and senior notes and debentures is as follows:
		December 31, 2014				December 31, 2013
		Carrying		Fair Value		Carrying		Fair Value
		Value				Value
		(In thousands)
	Mortgages and notes payable	$	854,217	$	880,866	$	889,278	$	912,251
	Senior notes and debentures	$	1,483,813	$	1,579,868	$	1,360,913	$	1,397,731
Summary of financial liabilities measured at fair value on a recurring basis	A summary of our financial liabilities that are measured at fair value on a recurring basis, by level within the fair value hierarchy is as follows:
		December 31, 2014								December 31, 2013
		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
		(In thousands)
	Interest rate swaps	$	—	$	3,515	$	—	$	3,515	$	—	$	1,417	$	—	$	1,417

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Minimum annual payments	We are obligated under ground lease agreements on several shopping centers requiring minimum annual payments as follows, as of December 31, 2014:
		(In thousands)
	Year ending December 31,
	2015	$	1,478
	2016	2,437
	2017	2,473
	2018	2,488
	2019	2,676
	Thereafter	154,211
		$	165,763

Dividends_Tables

Dividends (Tables)	12 Months Ended
	Dec. 31, 2014
Dividends [Abstract]
Summary of dividends declared and paid per share	The following table provides a summary of dividends declared and paid per share:
		Year Ended December 31,
		2014				2013				2012
		Declared		Paid		Declared		Paid		Declared		Paid
	Common shares	$	3.3	$	3.21	$	3.02	$	2.97	$	2.84	$	2.8
	5.417% Series 1 Cumulative Convertible Preferred shares	$	1.354	$	1.354	$	1.354	$	1.354	$	1.354	$	1.354
Summary of income tax status of dividends per share paid	A summary of the income tax status of dividends per share paid is as follows:
		Year Ended December 31,
		2014		2013		2012
	Common shares
	Ordinary dividend	$	3.178	$	2.911	$	2.772
	Capital gain	0.032		0.059		0.028
		$	3.21	$	2.97	$	2.8
	5.417% Series 1 Cumulative Convertible Preferred shares
	Ordinary dividend	$	1.34	$	1.327	$	1.34
	Capital gain	0.014		0.027		0.014
		$	1.354	$	1.354	$	1.354

Operating_Leases_Tables

Operating Leases (Tables)	12 Months Ended
	Dec. 31, 2014
Leases [Abstract]
Schedule of minimum future commercial property rentals from noncancelable operating leases	As of December 31, 2014, minimum future commercial property rentals from noncancelable operating leases, before any reserve for uncollectible amounts and assuming no early lease terminations, at our operating properties are as follows:
		(In thousands)
	Year ending December 31,
	2015	$	484,911
	2016	447,519
	2017	389,507
	2018	323,748
	2019	268,600
	Thereafter	1,718,254
		$	3,632,539

Components_of_Rental_Income_an

Components of Rental Income and Expense (Tables)	12 Months Ended
	Dec. 31, 2014
Components Of Rental Income and Expense [Abstract]
Schedule of principal components of rental income	The principal components of rental income are as follows:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	Minimum rents
	Retail and commercial	$	472,602	$	448,058	$	420,989
	Residential	36,099		28,902		27,611
	Cost reimbursement	135,592		122,578		112,424
	Percentage rent	10,169		9,359		8,568
	Other	11,860		11,192		10,522
	Total rental income	$	666,322	$	620,089	$	580,114
Schedule of minimum rents	Minimum rents include the following:
		Year Ended December 31,
		2014		2013		2012
		(In millions)
	Straight-line rents	$	5.1	$	5.4	$	6.1
	Net amortization of above and below market leases	$	2.4	$	3.1	$	1.1
Schedule of principal components of rental expenses	The principal components of rental expenses are as follows:
		Year Ended December 31,
		2014		2013		2012
		(In thousands)
	Repairs and maintenance	$	55,444	$	46,600	$	41,550
	Utilities	20,499		19,219		19,201
	Management fees and costs	17,416		16,250		15,167
	Payroll	11,554		9,237		8,691
	Marketing	9,532		8,664		7,321
	Insurance	6,462		6,811		6,267
	Ground Rent	1,952		1,916		2,189
	Bad debt expense	2,021		442		2,173
	Other operating	10,537		9,556		10,057
	Total rental expenses	$	135,417	$	118,695	$	112,616

Discontinued_Operations_Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
Summary of the financial information for the discontinued operations	A summary of the financial information for the discontinued operations is as follows:
		Year Ended December 31,
		2013		2012
		(in millions)
	Revenue from discontinued operations	$	1.5	$	2.2
	Income from discontinued operations	$	0.9	$	1.4

ShareBased_Compensation_Plans_

Share-Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of share-based compensation expense	A summary of share-based compensation expense included in net income is as follows:
		Year Ended December 31,
		2014				2013				2012
		(In thousands)
	Share-based compensation incurred
	Grants of common shares	$	12,892			$	10,907			$	9,846
	Grants of options	49				292				525
		12,941				11,199				10,371
	Capitalized share-based compensation	(1,188		)		(1,024		)		(908		)
	Share-based compensation expense	$	11,753			$	10,175			$	9,463
Summary of option activity	The following table provides a summary of option activity for 2014:
		Shares			Weighted-				Weighted-		Aggregate
		Under			Average				Average		Intrinsic
		Option			Exercise				Remaining		Value
					Price				Contractual Term
									(In years)		(In thousands)
	Outstanding at December 31, 2013	375,460			$	63
	Granted	—			—
	Exercised	(29,218	)		73.38
	Forfeited or expired	(2,500	)		82.15
	Outstanding at December 31, 2014	343,742			$	61.55			3.4		$	24,719
	Exercisable at December 31, 2014	343,599			$	61.55			3.4		$	24,709
Summary of restricted share activity	The following table provides a summary of restricted share activity for 2014:
		Shares			Weighted-Average
					Grant-Date Fair
					Value
	Unvested at December 31, 2013	298,203			$	93.71
	Granted	119,677			111.45
	Vested	(108,882	)		94.12
	Forfeited	(2,030	)		98.02
	Unvested at December 31, 2014	306,968			$	100.45
Schedule of common shares awarded under various compensation plans	Subsequent to December 31, 2014, common shares were awarded under various compensation plans as follows:
	Date		Award				Vesting Term		Beneficiary
	6-Feb-15		50,734		Restricted shares		2-5 years		Officers and key employees
	2-Jan-15		5,059		Shares		Immediate		Trustees

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Schedule of earnings per share	The conversions of downREIT operating partnership units and 5.417% Series 1 Cumulative Convertible Preferred Shares are anti-dilutive for all periods presented and accordingly, have been excluded from the weighted average common shares used to compute diluted EPS.
		Year Ended December 31,
		2014			2013			2012
		(In thousands, except per share data)
	NUMERATOR
	Income from continuing operations	$	167,888		$	137,811		$	142,972
	Less: Preferred share dividends	(541		)	(541		)	(541		)
	Less: Income from continuing operations attributable to noncontrolling interests	(7,754		)	(4,927		)	(4,307		)
	Less: Earnings allocated to unvested shares	(1,003		)	(889		)	(845		)
	Income from continuing operations available for common shareholders	158,590			131,454			137,279
	Results from discontinued operations attributable to the Trust	—			24,803			1,400
	Gain on sale of real estate	4,401			4,994			11,860
	Net income available for common shareholders, basic and diluted	$	162,991		$	161,251		$	150,539
	DENOMINATOR
	Weighted average common shares outstanding—basic	67,322			65,331			63,881
	Effect of dilutive securities:
	Stock options	170			152			175
	Weighted average common shares outstanding—diluted	67,492			65,483			64,056
	EARNINGS PER COMMON SHARE, BASIC
	Continuing operations	$	2.35		$	2.01		$	2.15
	Discontinued operations	—			0.38			0.02
	Gain on sale of real estate	0.07			0.08			0.19
		$	2.42		$	2.47		$	2.36
	EARNINGS PER COMMON SHARE, DILUTED
	Continuing operations	$	2.34		$	2		$	2.14
	Discontinued operations	—			0.38			0.02
	Gain on sale of real estate	0.07			0.08			0.19
		$	2.41		$	2.46		$	2.35
	Income from continuing operations attributable to the Trust	$	160,134		$	132,884		$	138,665

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Summary of quarterly financial data	Summarized quarterly financial data is as follows:
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
		(In thousands, except per share data)
	2014
	Revenue	$	170,828	$	167,947	$	170,938	$	176,377
	Operating income	$	63,444	$	68,361	$	67,622	$	71,610
	Net income(1)	$	40,545	$	45,416	$	49,049	$	37,279
	Net income attributable to the Trust(1)	$	38,753	$	43,545	$	47,075	$	35,162
	Net income available for common shareholders(1)	$	38,618	$	43,410	$	46,939	$	35,027
	Earnings per common share—basic(1)	$	0.58	$	0.64	$	0.69	$	0.51
	Earnings per common share—diluted(1)	$	0.57	$	0.64	$	0.69	$	0.51
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
		(In thousands, except per share data)
	2013
	Revenue(2)	$	157,149	$	157,388	$	159,030	$	163,846
	Operating income	$	62,502	$	63,488	$	64,701	$	63,470
	Net income(1)	$	35,842	$	38,797	$	63,366	$	29,603
	Net income attributable to the Trust(1)	$	34,588	$	37,539	$	62,098	$	28,456
	Net income available for common shareholders(1)	$	34,453	$	37,404	$	61,962	$	28,321
	Earnings per common share—basic(1)	$	0.53	$	0.57	$	0.94	$	0.43
	Earnings per common share—diluted(1)	$	0.53	$	0.57	$	0.94	$	0.42
	-1	Third quarter 2014 includes a $4.4 million gain on sale reflecting our share of the Partnership's sale of Pleasant Shops as further discussed in Note 5. Third quarter 2013 includes a $23.9 million gain on sale of two retail buildings as further discussed in Note 3.
	-2	Revenue in 2013 has been reduced to reflect the results of discontinued operations as further discussed in Note 14. Revenue from discontinued operations, by quarter, is summarized as follows:
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
		(In thousands)
	2013 revenue from discontinued operations	$	602	$	559	$	385	$	—

Business_And_Organization_Deta

Business And Organization (Details)	12 Months Ended
	Dec. 31, 2014
	project
Nature Of Operations [Abstract]
Number of real estate properties owned or had a majority interest in	89
Minimum percentage of taxable income distributed to shareholders	90.00%

Summary_Of_Significant_Account3

Summary Of Significant Accounting Policies (Revenue Recognition and Accounts Receivable) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Allowance for doubtful accounts	$12.40	$12.70
Collection of accounts receivable, period	1 year
Accounts receivable related to straight-line rents	$66.10	$60.60

Summary_Of_Significant_Account4

Summary Of Significant Accounting Policies (Real Estate) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Real estate depreciation expense	$155.70	$147.70	$128.70
Building and Building Improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	35 years
Building and Building Improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	50 years
Minor Improvements, Furniture and Equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Minor Improvements, Furniture and Equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years

Summary_Of_Significant_Account5

Summary Of Significant Accounting Policies (Cash and Cash Equivalents) (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Accounting Policies [Abstract]
Cash in excess of the FDIC insured limit	$47.70

Summary_Of_Significant_Account6

Summary Of Significant Accounting Policies (Derivative Instruments and Mortgage Notes Receivable) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Accounting Policies [Abstract]
Interest rate swaps associated with cash flow hedges to be reclassified within the next twelve months	$3.80
Residual profit maximum	50.00%

Summary_Of_Significant_Account7

Summary Of Significant Accounting Policies (Variable Interest Entities) (Details) (USD $)	0 Months Ended	12 Months Ended
	Oct. 16, 2006	Dec. 31, 2014	Dec. 31, 2013	Oct. 16, 2023	Oct. 16, 2021	Dec. 30, 2011
Variable Interest Entity [Line Items]
Mortgages payable		563,698,000	$588,456,000
Real estate, net		4,141,948,000	3,798,992,000
Melville Mall
Variable Interest Entity [Line Items]
Master lease term	20 years
Mortgages payable			20,700,000
Real estate, net		61,900,000	62,600,000
Melville Mall | Scenario, Forecast
Variable Interest Entity [Line Items]
Purchase price under option				5,000,000	5,000,000
Plaza El Segundo
Variable Interest Entity [Line Items]
Mortgages payable		180,300,000	182,100,000
Real estate, net		178,100,000	183,400,000
Ownership percentage						48.20%
Maximum exposure to loss		19,500,000
The Grove at Shrewsbury (East)
Variable Interest Entity [Line Items]
Mortgages payable		7,400,000
Real estate, net		15,700,000
Second Mortgage | Melville Mall
Variable Interest Entity [Line Items]
Mortgages payable	34,200,000
Darien
Variable Interest Entity [Line Items]
Maximum period of sale to defer gain on sale of other property, days		180 days

Summary_Of_Significant_Account8

Summary Of Significant Accounting Policies (Redeemable Noncontrolling Interests) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Rollforward of Redeemable Noncontrolling Interests
Beginning balance	$104,425	$94,420
Net income	3,452	2,887	2,592
Distributions & Redemptions	-3,714	-3,822
Contributions	5,858	1,083
Adjustment to redeemable noncontrolling interests	9,032	9,857
Ending balance	$119,053	$104,425	$94,420

Summary_Of_Significant_Account9

Summary Of Significant Accounting Policies (Income Taxes and Segments) (Details)	12 Months Ended
	Dec. 31, 2014
	segment
	properties
Accounting Policies [Abstract]
Minimum percentage of taxable income distributed to shareholders	90.00%
Number of properties exceeding segment reporting threshold	0
Segment reporting threshold	10% of our revenues or property operating income
Number of segments	1

Recovered_Sheet1

Summary Of Significant Accounting Policies (Supplemental Cash Flow Disclosures) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
SUPPLEMENTAL DISCLOSURES:
Total interest costs incurred	$114,912	$121,158	$123,441
Interest capitalized	-20,971	-16,181	-10,105
Interest expense	93,941	104,977	113,336
Cash paid for interest, net of amounts capitalized	100,011	120,934	114,419
Cash paid (refunded) for income taxes	278	410	-1,151
NON-CASH INVESTING AND FINANCING TRANSACTIONS:
Mortgage loans assumed with acquisition	68,282	0	67,615
DownREIT operating partnership units issued with acquisition	65,348	0	0
Mortgage loans refinanced	64,205	0	0
Repayment of note payable with public funding/related construction-in-progress offset	10,000	0	0
Shares issued under dividend reinvestment plan	$1,855	$1,779	$1,864
Minimum | Retail and commercial
Operating Leased Assets [Line Items]
Operating lease, term	3 years
Maximum | Retail and commercial
Operating Leased Assets [Line Items]
Operating lease, term	10 years

Real_Estate_Summary_Of_Real_Es

Real Estate (Summary Of Real Estate Investments) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Real Estate Properties [Line Items]
Cost	$5,608,998	$5,149,463
Accumulated Depreciation and Amortization	-1,467,050	-1,350,471
Encumbrances	635,345	660,127
Retail and mixed-use properties
Real Estate Properties [Line Items]
Cost	5,478,085	5,024,800
Accumulated Depreciation and Amortization	-1,423,682	-1,310,791
Encumbrances	541,568	565,935
Retail properties under capital leases
Real Estate Properties [Line Items]
Cost	121,069	115,028
Accumulated Depreciation and Amortization	-35,179	-31,955
Encumbrances	71,647	71,671
Residential
Real Estate Properties [Line Items]
Cost	9,844	9,635
Accumulated Depreciation and Amortization	-8,189	-7,725
Encumbrances	$22,130	$22,521

Real_Estate_Significant_Acquis

Real Estate (Significant Acquisitions and Disposition) (Details) (USD $)

3 Months Ended

12 Months Ended

0 Months Ended

24 Months Ended

0 Months Ended

Sep. 30, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Apr. 05, 2013

Jul. 22, 2013

Sep. 10, 2013

Jan. 02, 2014

Dec. 31, 2014

Apr. 03, 2013

Oct. 02, 2013

Dec. 19, 2013

acre

Business Acquisition [Line Items]

Mortgage loans assumed with acquisition

$68,282,000

$0

$67,615,000

Contributions from noncontrolling interests

65,350,000

175,000

Gain on sale of real estate

4,401,000

4,994,000

11,860,000

Discontinued operations - gain on sale of real estate

23,900,000

0

23,861,000

0

Shirlington

Business Acquisition [Line Items]

Proceeds from sale

6,500,000

Gain on sale of real estate

5,000,000

Fifth Avenue

Business Acquisition [Line Items]

Proceeds from sale

15,300,000

Discontinued operations - gain on sale of real estate

10,700,000

Forest Hills

Business Acquisition [Line Items]

Proceeds from sale

20,400,000

Discontinued operations - gain on sale of real estate

13,200,000

Land Parcel Adjacent to Assembly Row

Business Acquisition [Line Items]

Area of land

11.8

Land acquisition purchase price

18,000,000

Land Contiguous with Montrose Crossing

Business Acquisition [Line Items]

Land acquisition purchase price

10,500,000

Land acquistion, share of purchase price

9,400,000

Montrose Crossing

Business Acquisition [Line Items]

Ownership percentage

89.90%

The Grove at Shrewsbury

Business Acquisition [Line Items]

Leasable area (square feet)

187,000

Mandatorily redeemable noncontrolling interested classified as a liability

9,000,000

9,000,000

Brook 35

Business Acquisition [Line Items]

Leasable area (square feet)

99,000

Grove at Shrewsbury and Brook 35

Business Acquisition [Line Items]

Gross value

161,000,000

Effective economic interest percentage

84.00%

Mortgage loans assumed with acquisition

68,000,000

Number of downREIT operating partnership units

632,000

Cash payments to acquire businesses

13,000,000

Net assets acquired allocated to below market leases

2,300,000

Contributions from noncontrolling interests

71,100,000

Acquisition costs

1,000,000

1,000,000

2,000,000

Darien

Business Acquisition [Line Items]

Leasable area (square feet)

95,000

Net assets acquired allocated to below market leases

1,800,000

Acquisition costs

200,000

Business acquisition purchase price

47,300,000

Above Market Leases | Grove at Shrewsbury and Brook 35

Business Acquisition [Line Items]

Net assets acquired allocated to above market leases

1,700,000

Above Market Leases | Darien

Business Acquisition [Line Items]

Net assets acquired allocated to above market leases

$100,000

Mortgage_Notes_Receivable_Deta

Mortgage Notes Receivable (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014		Dec. 31, 2013	Aug. 04, 2006
	loan		loan
Mortgage Loans on Real Estate [Line Items]
Number of mortgage notes receivable	4		5
Carrying amount of mortgage notes receivable	$50,988,000	[1]	$55,200,000
Principal balance of first mortgage loan	51,942,000
Weighted average interest rate	9.00%		9.00%
First Mortgage
Mortgage Loans on Real Estate [Line Items]
Carrying amount of mortgage notes receivable	41,200,000		44,800,000
Second Mortgage On Hotel In San Jose, CA
Mortgage Loans on Real Estate [Line Items]
Number of mortgage notes receivable	1
Carrying amount of mortgage notes receivable	9,737,000	[2]
Principal balance of first mortgage loan	10,691,000		11,900,000
Valuation allowance	$1,000,000		$1,600,000
Weighted average interest rate	9.00%			14.00%
[1]	For Federal tax purposes, the aggregate tax basis is approximately $51.9 million as of December 31, 2014.
[2]	This note was amended on August 4, 2006. The amended note decreased the interest from 14% to 9% per annum, and requires monthly payments of principal and interest based on 15-year amortization schedule.

Real_Estate_Partnerships_Summa

Real Estate Partnerships (Summarized Operating Results and Financial Position of Partnership) (Details) (USD $)	3 Months Ended													12 Months Ended			0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014		Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 24, 2014	Dec. 31, 2011
OPERATING RESULTS
Revenue	$176,377	$170,938		$167,947	$170,828	$163,846	[1]	$159,030	[1]	$157,388	[1]	$157,149	[1]	$686,090	$637,413	$605,791
Depreciation and amortization														170,814	160,828	141,701
Interest expense														93,941	104,977	113,336
Income before gain on sale of real estate														167,888	162,614	144,372
Gain on sale of real estate														4,401	4,994	11,860
Net income	37,279	49,049	[2]	45,416	40,545	29,603		63,366	[2]	38,797		35,842		172,289	167,608	156,232
Our share of net income from real estate partnership before gain on sale of real estate														1,243	1,498	1,757
ASSETS
Real estate, net	4,141,948					3,798,992								4,141,948	3,798,992
Cash	47,951					88,927								47,951	88,927	36,988		67,806
Total assets	4,546,870					4,219,294								4,546,870	4,219,294
LIABILITIES AND PARTNERS' CAPITAL
Mortgages payable	563,698					588,456								563,698	588,456
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	4,546,870					4,219,294								4,546,870	4,219,294
Our investment in real estate partnership	37,457					32,264								37,457	32,264
Federal / Lion Venture LP
OPERATING RESULTS
Revenue														18,329	19,209	19,051
Other operating expenses														5,948	5,999	5,234
Depreciation and amortization														5,678	5,506	5,508
Interest expense														2,759	3,363	3,376
Total expenses														14,385	14,868	14,118
Income before gain on sale of real estate														3,944	4,341	4,933
Gain on sale of real estate														14,507	0	0	14,500
Net income														18,451	4,341	4,933
ASSETS
Real estate, net	149,203					170,867								149,203	170,867
Cash	2,864					2,210								2,864	2,210
Other assets	5,346					5,668								5,346	5,668
Total assets	157,413					178,745								157,413	178,745
LIABILITIES AND PARTNERS' CAPITAL
Mortgages payable	34,385					56,922								34,385	56,922
Other liabilities	3,673					4,100								3,673	4,100
Partners’ capital	119,355					117,723								119,355	117,723
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	157,413					178,745								157,413	178,745
Our share of unconsolidated debt	10,316					17,077								10,316	17,077
Our investment in real estate partnership	32,367					32,264								32,367	32,264
Federal Realty Investment Trust | Federal / Lion Venture LP
OPERATING RESULTS
Gain on sale of real estate																	4,400
Our share of net income from real estate partnership before gain on sale of real estate														1,423	1,498	1,815
Our share of gain on sale of real estate														$4,401	$0	$0
[1]	Revenue in 2013 has been reduced to reflect the results of discontinued operations as further discussed in Note 14. Revenue from discontinued operations, by quarter, is summarized as follows: FirstQuarter SecondQuarter ThirdQuarter FourthQuarter (In thousands)2013 revenue from discontinued operations$602 $559 $385 $—
[2]	Third quarter 2014 includes a $4.4 million gain on sale reflecting our share of the Partnership's sale of Pleasant Shops as further discussed in Note 5. Third quarter 2013 includes a $23.9 million gain on sale of two retail buildings as further discussed in Note 3.

Real_Estate_Partnerships_Narra

Real Estate Partnerships (Narrative) (Details) (USD $)	12 Months Ended			0 Months Ended		3 Months Ended	0 Months Ended		126 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 24, 2014	Oct. 31, 2011	Mar. 31, 2012	Jun. 05, 2014	Sep. 02, 2014	Dec. 31, 2014
	project				Building
Schedule of Equity Method Investments [Line Items]
Total number of properties in the portfolio	89								89
Gain on sale of real estate	$4,401,000	$4,994,000	$11,860,000
Gain on sale of portfolio	-10,406,000	0	0
Federal / Lion Venture LP
Schedule of Equity Method Investments [Line Items]
Total number of properties in the portfolio	6								6
Sales price				34,300,000
Gain on sale of real estate	14,507,000	0	0	14,500,000
Gain on sale of portfolio				32,800,000
Newbury Street Partnership
Schedule of Equity Method Investments [Line Items]
Sales price					44,000,000
Gain on sale of real estate						11,900,000
Number of real estate properties sold					3
Federal / Lion Venture LP
Schedule of Equity Method Investments [Line Items]
Capital contributions from partners							11,900,000
Clarion | Federal / Lion Venture LP
Schedule of Equity Method Investments [Line Items]
Ownership interest in partnership	70.00%								70.00%
Federal Realty Investment Trust | Federal / Lion Venture LP
Schedule of Equity Method Investments [Line Items]
Ownership interest in partnership	30.00%								30.00%
Contributions									48,800,000
Distributions									30,400,000
Capital contribution to acquire interest in joint venture							3,600,000	3,200,000
Gain on sale of real estate				4,400,000
Gain on sale of portfolio				10,400,000
Federal Realty Investment Trust | Newbury Street Partnership
Schedule of Equity Method Investments [Line Items]
Ownership interest in partnership					85.00%
Taurus Investment Holdings | Newbury Street Partnership
Schedule of Equity Method Investments [Line Items]
Ownership interest in partnership					15.00%
Federal / Lion Venture LP
Schedule of Equity Method Investments [Line Items]
Repayments of mortgage loans							11,900,000	10,500,000
Capital contributions from partners								$10,500,000

Acquired_InPlace_Leases_Detail

Acquired In-Place Leases (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Balance of acquired below market leases	$109,800,000	$111,100,000
Accumulated amortization of below market leases	37,000,000	34,900,000
Amortization from acquired below market lease	5,800,000	5,900,000	4,500,000
Below Market Leases
2015	5,327,000
2016	4,898,000
2017	4,653,000
2018	3,706,000
2019	3,610,000
Thereafter	50,632,000
Total future amortization expense from acquired below market leases	72,826,000
Above Market Leases
Acquired Finite-Lived Intangible Assets [Line Items]
Balance of acquired above market leases	32,700,000	31,100,000
Accumulated amortization of acquired above market leases	19,300,000	16,300,000
Amortization from acquired above market leases	3,400,000	2,800,000	3,400,000
Weighted-average amortization period	5 years 1 month
Above Market Leases
2015	2,892,000
2016	2,476,000
2017	1,784,000
2018	1,275,000
2019	923,000
Thereafter	4,012,000
Total future amortization expense from acquired above market leases	$13,362,000
Below Market Lease [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period	21 years 2 months

Debt_Narrative_Details

Debt (Narrative) (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 14, 2014		Dec. 12, 2014	Jan. 02, 2014
Debt Instrument [Line Items]
Net proceeds from note offering	$244,579,000	$564,389,000	$244,807,000
Maximum amount of borrowings outstanding	79,500,000	76,000,000	186,000,000
Weighted average amount of borrowings outstanding	12,500,000	10,500,000	1,500,000
Weighted average interest rate before amortization of debt fees	1.10%	1.30%	1.40%
Annual facility fee	900,000
Revolving credit facility, max capacity	600,000,000
4.50% notes
Debt Instrument [Line Items]
Principal balance				250,000,000	[1]
Net proceeds from note offering				244,600,000
Revolving credit facility | Notes Payable
Debt Instrument [Line Items]
Revolving credit facility	0	0
5.65% notes
Debt Instrument [Line Items]
Redemption price						134,500,000
Make-whole premium						9,200,000
Accrued but unpaid interest						200,000
Grove at Shrewsbury and Brook 35
Debt Instrument [Line Items]
Principal balance							68,300,000
Debt instrument, fair value							$73,800,000
[1]	The net proceeds from this note offering after issuance discounts, underwriting fees and other costs were approximately $244.6 million.

Debt_Summary_Of_Debt_Outstandi

Debt (Summary Of Debt Outstanding) (Details) (USD $)	8 Months Ended
In Thousands, unless otherwise specified	Aug. 27, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 15, 2014	Jun. 02, 2014	Nov. 14, 2014
Debt Instrument [Line Items]
Mortgages payable		$563,698	$588,456
Notes payable		290,519	300,822
Senior notes and debentures		1,483,813	1,360,913
Capital lease obligations		71,647	71,671
Total debt and capital lease obligations		2,409,677	2,321,862
THE AVENUE at White Marsh
Debt Instrument [Line Items]
Interest rate				3.35%
Brook 35
Debt Instrument [Line Items]
Interest rate					4.65%
Term loan
Debt Instrument [Line Items]
Variable Interest Rate	1.30%
4.50% notes
Debt Instrument [Line Items]
Principal balance						250,000	[1]
Interest rate						4.50%
Mortgages Payable
Debt Instrument [Line Items]
Principal balance		554,865	578,491
Net unamortized premium (discount)		8,833	9,965
Mortgages Payable | Melville Mall
Debt Instrument [Line Items]
Principal balance		0	20,705
Interest rate		5.25%
Mortgages Payable | THE AVENUE at White Marsh
Debt Instrument [Line Items]
Principal balance		0	54,112
Interest rate		5.46%
Mortgages Payable | Barracks Road
Debt Instrument [Line Items]
Principal balance		35,985	37,069
Interest rate		7.95%
Mortgages Payable | Hauppauge
Debt Instrument [Line Items]
Principal balance		13,566	13,974
Interest rate		7.95%
Mortgages Payable | Lawrence Park
Debt Instrument [Line Items]
Principal balance		25,507	26,275
Interest rate		7.95%
Mortgages Payable | Wildwood
Debt Instrument [Line Items]
Principal balance		22,420	23,095
Interest rate		7.95%
Mortgages Payable | Wynnewood
Debt Instrument [Line Items]
Principal balance		25,994	26,777
Interest rate		7.95%
Mortgages Payable | Brick Plaza
Debt Instrument [Line Items]
Principal balance		26,415	27,254
Interest rate		7.42%
Mortgages Payable | East Bay Bridge
Debt Instrument [Line Items]
Principal balance		0	61,980
Interest rate		5.13%
Mortgages Payable | Plaza El Segundo
Debt Instrument [Line Items]
Principal balance		175,000	175,000
Interest rate		6.33%
Mortgages Payable | The Grove at Shrewsbury (East)
Debt Instrument [Line Items]
Principal balance		44,519	0
Interest rate		5.82%
Mortgages Payable | The Grove at Shrewsbury (West)
Debt Instrument [Line Items]
Principal balance		11,242	0
Interest rate		6.38%
Mortgages Payable | Rollingwood Apartments
Debt Instrument [Line Items]
Principal balance		22,130	22,521
Interest rate		5.54%
Mortgages Payable | 29th Place
Debt Instrument [Line Items]
Principal balance		4,941	5,119
Interest rate		5.91%
Mortgages Payable | THE AVENUE at White Marsh
Debt Instrument [Line Items]
Principal balance		52,705	0
Interest rate		3.35%
Mortgages Payable | Montrose Crossing
Debt Instrument [Line Items]
Principal balance		75,867	77,341
Interest rate		4.20%
Mortgages Payable | Brook 35
Debt Instrument [Line Items]
Principal balance		11,500	0
Interest rate		4.65%
Mortgages Payable | Chelsea
Debt Instrument [Line Items]
Principal balance		7,074	7,269
Interest rate		5.36%
Notes Payable
Debt Instrument [Line Items]
Notes payable		290,519	300,822
Notes Payable | Escondido Promenade
Debt Instrument [Line Items]
Special Assessment Bond		9,400	9,400
Notes Payable | Escondido (municipal bonds)
Debt Instrument [Line Items]
Interest rate		0.06%
Notes Payable | Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility		0	0
Notes Payable | Term loan
Debt Instrument [Line Items]
Other Notes Payable		275,000	275,000
Notes Payable | Various
Debt Instrument [Line Items]
Interest rate		11.31%
Other Notes Payable		6,119	16,422
Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		1,494,200	1,369,200
Net unamortized premium (discount)		-10,387	-8,287
Senior Notes and Debentures | 5.65% notes
Debt Instrument [Line Items]
Principal balance		0	125,000
Interest rate		5.65%
Senior Notes and Debentures | 6.20% notes
Debt Instrument [Line Items]
Principal balance		200,000	200,000
Interest rate		6.20%
Senior Notes and Debentures | 5.90% notes
Debt Instrument [Line Items]
Principal balance		150,000	150,000
Interest rate		5.90%
Senior Notes and Debentures | 3.00% notes
Debt Instrument [Line Items]
Principal balance		250,000	250,000
Interest rate		3.00%
Senior Notes and Debentures | 2.75% notes
Debt Instrument [Line Items]
Principal balance		275,000	275,000
Interest rate		2.75%
Senior Notes and Debentures | 3.95% notes
Debt Instrument [Line Items]
Principal balance		300,000	300,000
Interest rate		3.95%
Senior Notes and Debentures | 7.48% debentures
Debt Instrument [Line Items]
Principal balance		29,200	29,200
Interest rate		7.48%
Senior Notes and Debentures | 6.82% medium term notes
Debt Instrument [Line Items]
Principal balance		40,000	40,000
Interest rate		6.82%
Senior Notes and Debentures | 4.50% notes
Debt Instrument [Line Items]
Principal balance		$250,000	$0
Interest rate		4.50%
[1]	The net proceeds from this note offering after issuance discounts, underwriting fees and other costs were approximately $244.6 million.

Debt_Acquired_Through_Acquisit

Debt (Acquired Through Acquisition) (Details) (USD $)	Jan. 02, 2014
In Thousands, unless otherwise specified
Brook 35
Debt Instrument [Line Items]
Principal	$11,500
Stated Interest Rate	5.46%
The Grove at Shrewsbury (East)
Debt Instrument [Line Items]
Principal	45,400
Stated Interest Rate	5.82%
The Grove at Shrewsbury (West)
Debt Instrument [Line Items]
Principal	$11,400
Stated Interest Rate	6.38%

Debt_Refinanced_or_Issued_Inst

Debt (Refinanced or Issued Instruments) (Details) (USD $)	Jun. 02, 2014	Nov. 14, 2014		Dec. 15, 2014
Brook 35
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$11,500,000
Interest rate	4.65%
4.50% notes
Debt Instrument [Line Items]
Principal balance		250,000,000	[1]
Interest rate		4.50%
THE AVENUE at White Marsh
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$52,700,000	[1]
Interest rate				3.35%
[1]	The net proceeds from this note offering after issuance discounts, underwriting fees and other costs were approximately $244.6 million.

Debt_Debt_Repayments_Details

Debt (Debt Repayments) (Details) (USD $)	0 Months Ended
In Millions, unless otherwise specified	Jun. 03, 2014	Dec. 10, 2014		Dec. 12, 2014
Melville Mall
Debt Instrument [Line Items]
Repayments of debt	$20.30
East Bay Bridge
Debt Instrument [Line Items]
Accrued but unpaid interest		0.1	[1]
RepaymentSecuredDebtIncludingPrepaymentPenalty		64
Prepayment premium on mortgage loan		3
Repayments of debt		61	[1]
5.65% notes
Debt Instrument [Line Items]
Accrued but unpaid interest				0.2
Repayments of debt				$125	[2]
[1]	The total amount due at payoff of $64.0 million included a prepayment premium of $3.0 million and accrued but unpaid interest of $0.1 million. The prepayment premium is included in "early extinguishment of debt" in 2014
[2]	The redemption price of $134.5 million included a make-whole premium of approximately $9.2 million and accrued but unpaid interest of $0.2 million. The make-whole premium is included in "early extinguishment of debt" in 2014.

Debt_Principal_Payments_On_Mor

Debt (Principal Payments On Mortgage Payable, Notes Payable, Senior Notes and Debentures) (Details) (USD $)	0 Months Ended	8 Months Ended
In Thousands, unless otherwise specified	Aug. 28, 2014	Aug. 27, 2014	Dec. 31, 2014
Debt Instrument [Line Items]
2015			$153,764
2016			13,580
2017			420,889
2018			288,826
2019			23,284
Thereafter			1,439,241
Long-term debt			2,339,584	[1]
Mortgages Payable
Debt Instrument [Line Items]
2015			153,395
2016			3,774
2017			220,438
2018			13,326
2019			22,731
Thereafter			141,201
Long-term debt			554,865
Notes Payable
Debt Instrument [Line Items]
2015			369
2016			9,806
2017			451	[2]
2018			275,500
2019			553
Thereafter			3,840
Long-term debt			290,519
Senior Notes and Debentures
Debt Instrument [Line Items]
2015			0
2016			0
2017			200,000
2018			0
2019			0
Thereafter			1,294,200
Long-term debt			$1,494,200
Term loan
Debt Instrument [Line Items]
Variable Interest Rate		1.30%
change in basis points spread	0.40%
LIBOR | Term loan
Debt Instrument [Line Items]
Variable Interest Rate	0.90%
[1]	The total debt maturities differ from the total reported on the consolidated balance sheet as of December 31, 2014 due to the unamortized discount or premium on certain senior notes and mortgages payable.
[2]	Our $600.0 million revolving credit facility matures on April 21, 2017, subject to a one-year extension at our option. As of December 31, 2014, there was no balance outstanding under this credit facility.

Debt_Future_Minimum_Lease_Paym

Debt (Future Minimum Lease Payments) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Debt Disclosure [Abstract]
2015	$5,787
2016	5,788
2017	5,797
2018	5,800
2019	5,800
Thereafter	160,210
Future minimum lease payments	189,182
Less amount representing interest	-117,535
Present value	$71,647

Fair_Value_Of_Financial_Instru2

Fair Value Of Financial Instruments (Summary Of Carrying Amount And Fair Value Of Financial Instruments) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes and debentures, carrying value	$1,483,813	$1,360,913
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgages and notes payable, carrying value	854,217	889,278
Senior notes and debentures, carrying value	1,483,813	1,360,913
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgages and notes payable, fair value	880,866	912,251
Senior notes and debentures, fair value	$1,579,868	$1,397,731

Fair_Value_Of_Financial_Instru3

Fair Value Of Financial Instruments (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	$290,519,000	$300,822,000
Other comprehensive (loss) income - change in value of interest rate swaps	-2,098,000	10,971,000	-8,448,000
Interest expense	93,941,000	104,977,000	113,336,000
Accumulated Other Comprehensive Loss
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other comprehensive (loss) income - change in value of interest rate swaps	-2,098,000	10,971,000	-8,448,000
Accumulated Other Comprehensive Loss | Reclassification out of Accumulated Other Comprehensive Income
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest expense	4,300,000
Notes Payable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	290,519,000	300,822,000
Term loan | Notes Payable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate	1.72%
Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of interest rate swap agreements	2
Interest Rate Swap | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap liability	3,515,000	1,417,000
Interest Rate Swap | Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional amount	$275,000,000

Fair_Value_Of_Financial_Instru4

Fair Value Of Financial Instruments (Summary of Financial Liabilities Measured At Fair Value On A Recurring Basis) (Details) (Interest Rate Swap, Fair Value, Measurements, Recurring, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Inputs, Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liability	$0
Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liability	3,515	1,417
Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap liability	$0

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2023	Sep. 30, 2025	Jan. 01, 2017	Oct. 16, 2023	Oct. 16, 2021
Loss Contingencies [Line Items]
Reserves for warranties and general liability	$7.20	$7.40
Payments from reserves	1.4	1.2
Letters of credit outstanding, amount	13
Operating partnership units, outstanding	917,255
Operating partnership units outstanding, fair value	122.4
Congressional Plaza | Put Option
Loss Contingencies [Line Items]
Maximum partnership percentage required to purchase	100.00%
Indexed ownership interest percentage	29.47%
Congressional Plaza | Put Option | Minimum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	72
Congressional Plaza | Put Option | Maximum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	76
Project In Southern California | Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	10.00%
Montrose Crossing | Minimum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	9
Montrose Crossing | Maximum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	10
Montrose Crossing | Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	10.10%
Plaza El Segundo | Minimum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	18
Plaza El Segundo | Maximum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	21
Plaza El Segundo | Put Option
Loss Contingencies [Line Items]
Number of members with purchase options	2
Scenario, Forecast | Mercer Mall
Loss Contingencies [Line Items]
Purchase price under option			55
Scenario, Forecast | Mercer Mall | Put Option
Loss Contingencies [Line Items]
Purchase price under option				60
Scenario, Forecast | Plaza El Segundo | Maximum
Loss Contingencies [Line Items]
Purchase price under option					4.9
Scenario, Forecast | The Grove at Shrewsbury | Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage					4.80%
Scenario, Forecast | Brook 35 | Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage					8.80%
Scenario, Forecast | Melville Mall
Loss Contingencies [Line Items]
Purchase price under option						5	5
Capital improvement, development, and redevelopment projects
Loss Contingencies [Line Items]
Contractual obligations	$232.30
Member One In Plaza El Segundo | Plaza El Segundo | Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	10.00%
Member Two In Plaza El Segundo | Plaza El Segundo | Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	11.80%

Commitments_and_Contingencies_2

Commitments and Contingencies (Schedule of Lease Payments) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2015	$1,478
2016	2,437
2017	2,473
2018	2,488
2019	2,676
Thereafter	154,211
Total	$165,763

Shareholders_Equity_Details

Shareholders' Equity (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 12, 2014
Class of Stock [Line Items]
Shares issued under dividend reinvestment plan (in shares)	18,705	20,026	22,814
Preferred shares, shares outstanding	399,896	399,896	399,896
Series 1 Cumulative Convertible Preferred interest rate	5.42%	5.42%	5.42%
Preferred shares, liquidation preference per share	$25	$25	$25
Preferred shares, par value	$0.01	$0.01	$0.01
Conversion price per share	$104.69
Net cash proceeds of common stock	$216,155,000	$186,548,000	$112,270,000
Common shares of beneficial interest, par	$0.01	$0.01
At The Market Equity Program
Class of Stock [Line Items]
Aggregate offering price of common shares				300,000,000
Shares issued under equity program	1,768,583	1,734,974
Weighted average price per common share	$122.09	$108.01
Net cash proceeds of common stock	213,600,000	185,200,000
Remaining capacity to issue	84,100,000
At The Market Equity Program | Commissions
Class of Stock [Line Items]
Commissions related to sales of common shares	2,200,000	2,000,000
At The Market Equity Program | Other Offering Costs
Class of Stock [Line Items]
Commissions related to sales of common shares	$200,000	$200,000

Dividends_Details

Dividends (Details) (USD $)	0 Months Ended	12 Months Ended
	Oct. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Dividends [Abstract]
Common shares, declared	$0.87	$3.30	$3.02	$2.84
5.417% Series 1 Cumulative Convertible Preferred shares, declared		$1.35	$1.35	$1.35
Common shares, paid		$3.21	$2.97	$2.80
5.417% Series 1 Cumulative Convertible Preferred shares, paid		$1.35	$1.35	$1.35
Common shares, ordinary dividend		$3.18	$2.91	$2.77
Common shares, capital gain		$0.03	$0.06	$0.03
5.417% Series 1 Cumulative Convertible Preferred shares, ordinary dividend		$1.34	$1.33	$1.34
5.417% Series 1 Cumulative Convertible Preferred shares, capital gain		$0.01	$0.03	$0.01
Series 1 Cumulative Convertible Preferred interest rate		5.42%	5.42%	5.42%
Common Stock, Ordinary Dividends, Tax Rate		15.00%	15.00%	15.00%
Preferred Stock, Ordinary Dividends, Tax Rate		15.00%	15.00%	15.00%

Operating_Leases_Details

Operating Leases (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Property Subject to or Available for Operating Lease [Line Items]
Number of real estate properties owned or had a majority interest in	89
Number of states in which entity has properties	13
Number of leases	2,700
Percent of annualized base rent	3.10%
Operating Leases, Future Minimum Payments Receivable [Abstract]
2015	484,911
2016	447,519
2017	389,507
2018	323,748
2019	268,600
Thereafter	1,718,254
Total	3,632,539
Retail and commercial | Minimum
Property Subject to or Available for Operating Lease [Line Items]
Operating lease, term	3 years
Retail and commercial | Maximum
Property Subject to or Available for Operating Lease [Line Items]
Operating lease, term	10 years
Residential | Maximum
Property Subject to or Available for Operating Lease [Line Items]
Operating lease, term	1 year

Components_of_Rental_Income_an1

Components of Rental Income and Expense (Schedule Of Principal Components Of Rental Income) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Leases, Income Statement, Lease Revenue [Abstract]
Cost reimbursement	$135,592	$122,578	$112,424
Percentage rent	10,169	9,359	8,568
Other	11,860	11,192	10,522
Total rental income	666,322	620,089	580,114
Retail and commercial
Operating Leases, Income Statement, Lease Revenue [Abstract]
Minimum rents	472,602	448,058	420,989
Residential
Operating Leases, Income Statement, Lease Revenue [Abstract]
Minimum rents	$36,099	$28,902	$27,611

Components_of_Rental_Income_an2

Components of Rental Income and Expense (Schedule Of Minimum Rent) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components Of Rental Income and Expense [Abstract]
Straight-line rents	$5.10	$5.40	$6.10
Net amortization of above and below market leases	$2.40	$3.10	$1.10

Components_of_Rental_Income_an3

Components of Rental Income and Expense (Components Of Rental Expenses) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components Of Rental Income and Expense [Abstract]
Repairs and maintenance	$55,444	$46,600	$41,550
Utilities	20,499	19,219	19,201
Management fees and costs	17,416	16,250	15,167
Payroll	11,554	9,237	8,691
Marketing	9,532	8,664	7,321
Insurance	6,462	6,811	6,267
Ground Rent	1,952	1,916	2,189
Bad debt expense	2,021	442	2,173
Other operating	10,537	9,556	10,057
Total rental expenses	$135,417	$118,695	$112,616

Discontinued_Operations_Summar

Discontinued Operations (Summary Of The Financial Information For The Discontinued Operations) (Details) (USD $)	3 Months Ended				12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Discontinued Operations and Disposal Groups [Abstract]
Revenue from discontinued operations	$0	$385	$559	$602		$1,500	$2,200
Income from discontinued operations					$0	$942	$1,400

ShareBased_Compensation_Plans_1

Share-Based Compensation Plans (Allocated Share-Based Compensation) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Share-based compensation incurred	$12,941	$11,199	$10,371
Capitalized share-based compensation	-1,188	-1,024	-908
Share-based compensation expense	11,753	10,175	9,463
Restricted Stock
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Share-based compensation incurred	12,892	10,907	9,846
Employee Stock Option
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Share-based compensation incurred	$49	$292	$525

ShareBased_Compensation_Plans_2

Share-Based Compensation Plans (Schedule of Option Activity) (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at the beginning of year (in shares)	375,460
Granted (in shares)	0	0	0
Exercised (in shares)	-29,218
Forfeited or expired (in shares)	-2,500
Outstanding at the end of year (in shares)	343,742	375,460
Exercisable at the end of year (in shares)	343,599
Outstanding at the beginning of year, Weighted-Average Exercise Price (in dollars per share)	$63
Granted, Weighted-Average Exercise Price (in dollars per share)	$0
Exercised, Weighted-Average Exercise Price (in dollars per share)	$73.38
Forfeited or Expired, Weighted-Average Exercise Price (in dollars per share)	$82.15
Outstanding at the end of year, Weighted-Average Exercise Price (in dollars per share)	$61.55	$63
Exercisable at the end of the year, Weighted-Average Exercise Price (in dollars per share)	$61.55
Outstanding at the end of year, Weighted-Average Remaining Contractual Term (in years)	3 years 5 months
Exercisable at the end of year, Weighted-Average Remaining Contractual Term (in years)	3 years 5 months
Outstanding at the end of year, Aggregate Intrinsic Value	$24,719
Exercisable at the end of year, Aggregate Intrinsic Value	$24,709

ShareBased_Compensation_Plans_3

Share-Based Compensation Plans (Restricted Share Activity) (Details) (Restricted Stock, USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested at the beginning of year (in shares)	298,203
Granted (in shares)	119,677
Vested (in shares)	-108,882
Forfeited (in shares)	-2,030
Unvested at the end of year (in shares)	306,968	298,203
Unvested at the beginning of year, Weighted-Average Grant-Date Fair Value (in dollars per share)	$93.71
Granted, Weighted-Average Grant-Date Fair Value (in dollars per share)	$111.45	$106.70	$96.35
Vested, Weighted-Average Grant-Date Fair Value (in dollars per share)	$94.12
Forfeited, Weighted-Average Grant-Date Fair Value (in dollars per share)	$98.02
Unvested at the end of year, Weighted-Average Grant-Date Fair Value (in dollars per share)	$100.45	$93.71

ShareBased_Compensation_Plans_4

Share-Based Compensation Plans (Narrative) (Details) (USD $)	12 Months Ended			0 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 07, 2014	Jan. 02, 2015	Feb. 06, 2015
	plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans	2
Number of options granted in period	0	0	0
Total cash received from options exercised	$2.30	$1	$5.70
Total intrinsic value of options exercised	1.1	0.7	4.2
Total unrecognized compensation cost related to unvested share-based compensation arrangements	15.5
Period for recognition (in years)	9 years 5 months
Weighted-average period for recognition	2 years 1 month
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	6 years
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term (in years)	10 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of stock awarded	$111.45	$106.70	$96.35
Total vesting-date fair value of shares vested during the year	$12.10	$10.60	$10.30
Granted (in shares)	119,677
Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				2 years
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				5 years
Performance Incentive Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,450,000
Long Term Incentive Plan 2001
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	3,250,000
Stock Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					5,059
Stock Award | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)						50,734

Savings_and_Retirement_Plans_D

Savings and Retirement Plans (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Plan
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Maximum annual contribution per employee	$17,500	$17,500	$17,000
Employer match as a percent	50.00%	50.00%	50.00%
Employer contribution expense	442,000	384,000	427,000
Deferred Compensation Arrangement with Individual, by Type of Compensation, Pension and Other Postretirement Benefits
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Liability to participants	$10,300,000	$9,200,000
Maximum | Pension Plan
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Maximum of employer match as a percentage of employee eligible earnings	5.00%	5.00%	5.00%

Earnings_Per_Share_Narrative_D

Earnings Per Share (Narrative) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share [Abstract]
Weighted average unvested shares outstanding	300,000	300,000	300,000
Anti-dilutive stock options excluded from dilutive earnings per share calculation	0	0	0
Cumulative convertible preferred share, dividend rate	5.42%	5.42%	5.42%

Earnings_Per_Share_Schedule_Of

Earnings Per Share (Schedule Of Earnings Per Share) (Details) (USD $)	3 Months Ended										12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014		Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013		Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share [Abstract]
Income from continuing operations											$167,888	$137,811	$142,972
Less: Preferred share dividends											-541	-541	-541
Less: Income from continuing operations attributable to noncontrolling interests											-7,754	-4,927	-4,307
Less: Earnings allocated to unvested shares											-1,003	-889	-845
Income from continuing operations available for common shareholders											158,590	131,454	137,279
Results from discontinued operations attributable to the Trust											0	24,803	1,400
Gain on sale of real estate											4,401	4,994	11,860
Net income available for common shareholders, basic and diluted											162,991	161,251	150,539
Weighted average common shares outstanding—basic											67,322	65,331	63,881
Stock options											170	152	175
Weighted average common shares outstanding—diluted											67,492	65,483	64,056
Continuing operations											$2.35	$2.01	$2.15
Discontinued operations											$0	$0.38	$0.02
Gain on sale of real estate											$0.07	$0.08	$0.19
EARNINGS PER COMMON SHARE, BASIC	$0.51	$0.69	[1]	$0.64	$0.58	$0.43	$0.94	[1]	$0.57	$0.53	$2.42	$2.47	$2.36
Continuing operations											$2.34	$2	$2.14
Discontinued operations											$0	$0.38	$0.02
Gain on sale of real estate											$0.07	$0.08	$0.19
EARNINGS PER COMMON SHARE, DILUTED	$0.51	$0.69	[1]	$0.64	$0.57	$0.42	$0.94		$0.57	$0.53	$2.41	$2.46	$2.35
Income from continuing operations attributable to the Trust											$160,134	$132,884	$138,665
[1]	Third quarter 2014 includes a $4.4 million gain on sale reflecting our share of the Partnership's sale of Pleasant Shops as further discussed in Note 5. Third quarter 2013 includes a $23.9 million gain on sale of two retail buildings as further discussed in Note 3.

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data (Unaudited) Summary Of Quarterly Financial Data (Details) (USD $)	3 Months Ended													12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014		Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Revenue	$176,377	$170,938		$167,947	$170,828	$163,846	[1]	$159,030	[1]	$157,388	[1]	$157,149	[1]	$686,090	$637,413	$605,791
Operating income	71,610	67,622		68,361	63,444	63,470		64,701		63,488		62,502		271,037	254,161	253,862
Net income	37,279	49,049	[2]	45,416	40,545	29,603		63,366	[2]	38,797		35,842		172,289	167,608	156,232
NET INCOME ATTRIBUTABLE TO THE TRUST	35,162	47,075	[2]	43,545	38,753	28,456		62,098	[2]	37,539		34,588		164,535	162,681	151,925
Net income available for common shareholders	$35,027	$46,939	[2]	$43,410	$38,618	$28,321		$61,962	[2]	$37,404		$34,453		$163,994	$162,140	$151,384
Earnings per common share-basic	$0.51	$0.69	[2]	$0.64	$0.58	$0.43		$0.94	[2]	$0.57		$0.53		$2.42	$2.47	$2.36
Earnings per common share-diluted	$0.51	$0.69	[2]	$0.64	$0.57	$0.42		$0.94		$0.57		$0.53		$2.41	$2.46	$2.35
[1]	Revenue in 2013 has been reduced to reflect the results of discontinued operations as further discussed in Note 14. Revenue from discontinued operations, by quarter, is summarized as follows: FirstQuarter SecondQuarter ThirdQuarter FourthQuarter (In thousands)2013 revenue from discontinued operations$602 $559 $385 $—
[2]	Third quarter 2014 includes a $4.4 million gain on sale reflecting our share of the Partnership's sale of Pleasant Shops as further discussed in Note 5. Third quarter 2013 includes a $23.9 million gain on sale of two retail buildings as further discussed in Note 3.

Selected_Quarterly_Financial_D3

Selected Quarterly Financial Data (Unaudited) (Details) (USD $)	3 Months Ended				12 Months Ended			3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operations - gain on sale of real estate		$23,900			$0	$23,861	$0
Revenue from discontinued operations	0	385	559	602		1,500	2,200
Feasterville Shopping Center July 17, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operations - gain on sale of real estate								$4,400

Subsequent_Event_Details

Subsequent Event (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 09, 2015
Subsequent Event [Line Items]
Mortgage loans assumed with acquisition	$68,282,000	$0	$67,615,000
San Antonio Center
Subsequent Event [Line Items]
Acquisition costs	700,000
San Antonio Center | Subsequent Event
Subsequent Event [Line Items]
Leasable area (square feet)				376,000
Gross value				62,200,000
Effective interest percentage				80.00%
Mortgage loans assumed with acquisition				18,700,000
Interest rate				5.27%
Number of downREIT operating partnership units				58,000
Cash payments to acquire businesses				$27,000,000

Schedule_III_Summary_of_Real_E1

Schedule III - Summary of Real Estate and Accumulated Depreciation (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	$635,345	$660,127
Initial cost to company, Land	1,116,102
Initial cost to company, Buildings and Improvements	1,781,103
Cost Capitalized Subsequent to Acquisition	2,711,793
Gross amount at which carried at close of period, Land	1,102,836
Gross amount at which carried at close of period, Buildings and Improvements	4,506,162
Gross amount at which carried at close of period, Total	5,608,998	5,149,463	4,779,674	4,426,444
Accumulated Depreciation and Amortization	1,467,050	1,350,471	1,224,295	1,127,588
150 Post Street
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	11,685
Initial cost to company, Buildings and Improvements	9,181
Cost Capitalized Subsequent to Acquisition	16,350
Gross amount at which carried at close of period, Land	11,685
Gross amount at which carried at close of period, Buildings and Improvements	25,531
Gross amount at which carried at close of period, Total	37,216
Accumulated Depreciation and Amortization	16,363
Life on which depreciation in latest income statements is computed	35 years
29th Place
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	4,917
Initial cost to company, Land	10,211
Initial cost to company, Buildings and Improvements	18,863
Cost Capitalized Subsequent to Acquisition	11,222
Gross amount at which carried at close of period, Land	10,225
Gross amount at which carried at close of period, Buildings and Improvements	30,071
Gross amount at which carried at close of period, Total	40,296
Accumulated Depreciation and Amortization	7,323
Life on which depreciation in latest income statements is computed	35 years
Andorra
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	2,432
Initial cost to company, Buildings and Improvements	12,346
Cost Capitalized Subsequent to Acquisition	10,875
Gross amount at which carried at close of period, Land	2,432
Gross amount at which carried at close of period, Buildings and Improvements	23,221
Gross amount at which carried at close of period, Total	25,653
Accumulated Depreciation and Amortization	17,090
Life on which depreciation in latest income statements is computed	35 years
Assembly Row/Assembly Square Market Place
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	93,252
Initial cost to company, Buildings and Improvements	34,196
Cost Capitalized Subsequent to Acquisition	305,854
Gross amount at which carried at close of period, Land	93,252
Gross amount at which carried at close of period, Buildings and Improvements	340,050
Gross amount at which carried at close of period, Total	433,302
Accumulated Depreciation and Amortization	21,953
Life on which depreciation in latest income statements is computed	35 years
The Avenue at White Marsh
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	52,705
Initial cost to company, Land	20,682
Initial cost to company, Buildings and Improvements	72,432
Cost Capitalized Subsequent to Acquisition	4,514
Gross amount at which carried at close of period, Land	20,685
Gross amount at which carried at close of period, Buildings and Improvements	76,943
Gross amount at which carried at close of period, Total	97,628
Accumulated Depreciation and Amortization	22,282
Life on which depreciation in latest income statements is computed	35 years
Bala Cynwyd
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,565
Initial cost to company, Buildings and Improvements	14,466
Cost Capitalized Subsequent to Acquisition	22,187
Gross amount at which carried at close of period, Land	3,566
Gross amount at which carried at close of period, Buildings and Improvements	36,652
Gross amount at which carried at close of period, Total	40,218
Accumulated Depreciation and Amortization	16,281
Life on which depreciation in latest income statements is computed	35 years
Barracks Road
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	35,985
Initial cost to company, Land	4,363
Initial cost to company, Buildings and Improvements	16,459
Cost Capitalized Subsequent to Acquisition	39,643
Gross amount at which carried at close of period, Land	4,363
Gross amount at which carried at close of period, Buildings and Improvements	56,102
Gross amount at which carried at close of period, Total	60,465
Accumulated Depreciation and Amortization	37,539
Life on which depreciation in latest income statements is computed	35 years
Bethesda Row
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	46,579
Initial cost to company, Buildings and Improvements	35,406
Cost Capitalized Subsequent to Acquisition	141,226
Gross amount at which carried at close of period, Land	44,880
Gross amount at which carried at close of period, Buildings and Improvements	178,331
Gross amount at which carried at close of period, Total	223,211
Accumulated Depreciation and Amortization	56,776
Bethesda Row | Minimum
Real Estate and Accumulated Depreciation [Line Items]
Life on which depreciation in latest income statements is computed	35 years
Bethesda Row | Maximum
Real Estate and Accumulated Depreciation [Line Items]
Life on which depreciation in latest income statements is computed	50 years
Brick Plaza
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	26,415
Initial cost to company, Land	0
Initial cost to company, Buildings and Improvements	24,715
Cost Capitalized Subsequent to Acquisition	35,770
Gross amount at which carried at close of period, Land	3,944
Gross amount at which carried at close of period, Buildings and Improvements	56,541
Gross amount at which carried at close of period, Total	60,485
Accumulated Depreciation and Amortization	42,119
Life on which depreciation in latest income statements is computed	35 years
Bristol Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,856
Initial cost to company, Buildings and Improvements	15,959
Cost Capitalized Subsequent to Acquisition	9,602
Gross amount at which carried at close of period, Land	3,856
Gross amount at which carried at close of period, Buildings and Improvements	25,561
Gross amount at which carried at close of period, Total	29,417
Accumulated Depreciation and Amortization	14,521
Life on which depreciation in latest income statements is computed	35 years
Brook 35
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	11,500
Initial cost to company, Land	7,128
Initial cost to company, Buildings and Improvements	38,355
Cost Capitalized Subsequent to Acquisition	573
Gross amount at which carried at close of period, Land	7,128
Gross amount at which carried at close of period, Buildings and Improvements	38,928
Gross amount at which carried at close of period, Total	46,056
Accumulated Depreciation and Amortization	1,312
Life on which depreciation in latest income statements is computed	35 years
Chelsea Commons
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	6,790
Initial cost to company, Land	9,417
Initial cost to company, Buildings and Improvements	19,466
Cost Capitalized Subsequent to Acquisition	13,825
Gross amount at which carried at close of period, Land	9,396
Gross amount at which carried at close of period, Buildings and Improvements	33,312
Gross amount at which carried at close of period, Total	42,708
Accumulated Depreciation and Amortization	5,484
Life on which depreciation in latest income statements is computed	35 years
Colorado Blvd
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	5,262
Initial cost to company, Buildings and Improvements	4,071
Cost Capitalized Subsequent to Acquisition	8,787
Gross amount at which carried at close of period, Land	5,262
Gross amount at which carried at close of period, Buildings and Improvements	12,858
Gross amount at which carried at close of period, Total	18,120
Accumulated Depreciation and Amortization	9,336
Life on which depreciation in latest income statements is computed	35 years
Congressional Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	2,793
Initial cost to company, Buildings and Improvements	7,424
Cost Capitalized Subsequent to Acquisition	69,801
Gross amount at which carried at close of period, Land	1,020
Gross amount at which carried at close of period, Buildings and Improvements	78,998
Gross amount at which carried at close of period, Total	80,018
Accumulated Depreciation and Amortization	47,425
Life on which depreciation in latest income statements is computed	35 years
Courthouse Center
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,750
Initial cost to company, Buildings and Improvements	1,869
Cost Capitalized Subsequent to Acquisition	1,142
Gross amount at which carried at close of period, Land	1,750
Gross amount at which carried at close of period, Buildings and Improvements	3,011
Gross amount at which carried at close of period, Total	4,761
Accumulated Depreciation and Amortization	1,589
Life on which depreciation in latest income statements is computed	35 years
Courtyard Shops
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	16,862
Initial cost to company, Buildings and Improvements	21,851
Cost Capitalized Subsequent to Acquisition	2,025
Gross amount at which carried at close of period, Land	16,894
Gross amount at which carried at close of period, Buildings and Improvements	23,844
Gross amount at which carried at close of period, Total	40,738
Accumulated Depreciation and Amortization	5,731
Life on which depreciation in latest income statements is computed	35 years
Crossroads
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	4,635
Initial cost to company, Buildings and Improvements	11,611
Cost Capitalized Subsequent to Acquisition	14,897
Gross amount at which carried at close of period, Land	4,635
Gross amount at which carried at close of period, Buildings and Improvements	26,508
Gross amount at which carried at close of period, Total	31,143
Accumulated Depreciation and Amortization	14,056
Life on which depreciation in latest income statements is computed	35 years
Crow Canyon Commons
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	27,245
Initial cost to company, Buildings and Improvements	54,575
Cost Capitalized Subsequent to Acquisition	4,915
Gross amount at which carried at close of period, Land	27,245
Gross amount at which carried at close of period, Buildings and Improvements	59,490
Gross amount at which carried at close of period, Total	86,735
Accumulated Depreciation and Amortization	15,878
Life on which depreciation in latest income statements is computed	35 years
Darien
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	29,809
Initial cost to company, Buildings and Improvements	18,302
Cost Capitalized Subsequent to Acquisition	21
Gross amount at which carried at close of period, Land	29,809
Gross amount at which carried at close of period, Buildings and Improvements	18,323
Gross amount at which carried at close of period, Total	48,132
Accumulated Depreciation and Amortization	1,134
Life on which depreciation in latest income statements is computed	35 years
Dedham Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	12,287
Initial cost to company, Buildings and Improvements	12,918
Cost Capitalized Subsequent to Acquisition	9,834
Gross amount at which carried at close of period, Land	12,287
Gross amount at which carried at close of period, Buildings and Improvements	22,752
Gross amount at which carried at close of period, Total	35,039
Accumulated Depreciation and Amortization	12,909
Life on which depreciation in latest income statements is computed	35 years
Del Mar Village
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	15,624
Initial cost to company, Buildings and Improvements	41,712
Cost Capitalized Subsequent to Acquisition	2,494
Gross amount at which carried at close of period, Land	15,587
Gross amount at which carried at close of period, Buildings and Improvements	44,243
Gross amount at which carried at close of period, Total	59,830
Accumulated Depreciation and Amortization	15,971
Life on which depreciation in latest income statements is computed	35 years
East Bay Bridge
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	29,079
Initial cost to company, Buildings and Improvements	138,035
Cost Capitalized Subsequent to Acquisition	1,395
Gross amount at which carried at close of period, Land	29,079
Gross amount at which carried at close of period, Buildings and Improvements	139,430
Gross amount at which carried at close of period, Total	168,509
Accumulated Depreciation and Amortization	9,604
Life on which depreciation in latest income statements is computed	35 years
Eastgate
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,608
Initial cost to company, Buildings and Improvements	5,775
Cost Capitalized Subsequent to Acquisition	20,329
Gross amount at which carried at close of period, Land	1,608
Gross amount at which carried at close of period, Buildings and Improvements	26,104
Gross amount at which carried at close of period, Total	27,712
Accumulated Depreciation and Amortization	17,343
Life on which depreciation in latest income statements is computed	35 years
Elllisburg
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	4,028
Initial cost to company, Buildings and Improvements	11,309
Cost Capitalized Subsequent to Acquisition	18,818
Gross amount at which carried at close of period, Land	4,013
Gross amount at which carried at close of period, Buildings and Improvements	30,142
Gross amount at which carried at close of period, Total	34,155
Accumulated Depreciation and Amortization	17,344
Life on which depreciation in latest income statements is computed	35 years
Escondido Promenade
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	19,117
Initial cost to company, Buildings and Improvements	15,829
Cost Capitalized Subsequent to Acquisition	12,118
Gross amount at which carried at close of period, Land	19,117
Gross amount at which carried at close of period, Buildings and Improvements	27,947
Gross amount at which carried at close of period, Total	47,064
Accumulated Depreciation and Amortization	12,034
Life on which depreciation in latest income statements is computed	35 years
Falls Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,798
Initial cost to company, Buildings and Improvements	1,270
Cost Capitalized Subsequent to Acquisition	9,787
Gross amount at which carried at close of period, Land	1,819
Gross amount at which carried at close of period, Buildings and Improvements	11,036
Gross amount at which carried at close of period, Total	12,855
Accumulated Depreciation and Amortization	7,607
Life on which depreciation in latest income statements is computed	25 years
Federal Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	10,216
Initial cost to company, Buildings and Improvements	17,895
Cost Capitalized Subsequent to Acquisition	37,699
Gross amount at which carried at close of period, Land	10,216
Gross amount at which carried at close of period, Buildings and Improvements	55,594
Gross amount at which carried at close of period, Total	65,810
Accumulated Depreciation and Amortization	37,299
Life on which depreciation in latest income statements is computed	35 years
Finley Square
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	9,252
Initial cost to company, Buildings and Improvements	9,544
Cost Capitalized Subsequent to Acquisition	13,829
Gross amount at which carried at close of period, Land	9,252
Gross amount at which carried at close of period, Buildings and Improvements	23,373
Gross amount at which carried at close of period, Total	32,625
Accumulated Depreciation and Amortization	16,607
Life on which depreciation in latest income statements is computed	35 years
Flourtown
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,345
Initial cost to company, Buildings and Improvements	3,943
Cost Capitalized Subsequent to Acquisition	9,010
Gross amount at which carried at close of period, Land	1,345
Gross amount at which carried at close of period, Buildings and Improvements	12,953
Gross amount at which carried at close of period, Total	14,298
Accumulated Depreciation and Amortization	4,490
Life on which depreciation in latest income statements is computed	35 years
Fresh Meadows
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	24,625
Initial cost to company, Buildings and Improvements	25,255
Cost Capitalized Subsequent to Acquisition	30,115
Gross amount at which carried at close of period, Land	24,633
Gross amount at which carried at close of period, Buildings and Improvements	55,362
Gross amount at which carried at close of period, Total	79,995
Accumulated Depreciation and Amortization	30,687
Life on which depreciation in latest income statements is computed	35 years
Friendship Center
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	12,696
Initial cost to company, Buildings and Improvements	20,803
Cost Capitalized Subsequent to Acquisition	3,999
Gross amount at which carried at close of period, Land	12,696
Gross amount at which carried at close of period, Buildings and Improvements	24,802
Gross amount at which carried at close of period, Total	37,498
Accumulated Depreciation and Amortization	8,889
Life on which depreciation in latest income statements is computed	35 years
Gaithersburg Square
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	7,701
Initial cost to company, Buildings and Improvements	5,271
Cost Capitalized Subsequent to Acquisition	12,810
Gross amount at which carried at close of period, Land	5,973
Gross amount at which carried at close of period, Buildings and Improvements	19,809
Gross amount at which carried at close of period, Total	25,782
Accumulated Depreciation and Amortization	15,980
Life on which depreciation in latest income statements is computed	35 years
Garden Market
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	2,677
Initial cost to company, Buildings and Improvements	4,829
Cost Capitalized Subsequent to Acquisition	5,181
Gross amount at which carried at close of period, Land	2,677
Gross amount at which carried at close of period, Buildings and Improvements	10,010
Gross amount at which carried at close of period, Total	12,687
Accumulated Depreciation and Amortization	6,111
Life on which depreciation in latest income statements is computed	35 years
Governor Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	2,068
Initial cost to company, Buildings and Improvements	4,905
Cost Capitalized Subsequent to Acquisition	19,744
Gross amount at which carried at close of period, Land	2,068
Gross amount at which carried at close of period, Buildings and Improvements	24,649
Gross amount at which carried at close of period, Total	26,717
Accumulated Depreciation and Amortization	17,018
Life on which depreciation in latest income statements is computed	35 years
Graham Park Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,237
Initial cost to company, Buildings and Improvements	15,096
Cost Capitalized Subsequent to Acquisition	17,536
Gross amount at which carried at close of period, Land	1,169
Gross amount at which carried at close of period, Buildings and Improvements	32,700
Gross amount at which carried at close of period, Total	33,869
Accumulated Depreciation and Amortization	24,764
Life on which depreciation in latest income statements is computed	35 years
Gratiot Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	525
Initial cost to company, Buildings and Improvements	1,601
Cost Capitalized Subsequent to Acquisition	17,092
Gross amount at which carried at close of period, Land	525
Gross amount at which carried at close of period, Buildings and Improvements	18,693
Gross amount at which carried at close of period, Total	19,218
Accumulated Depreciation and Amortization	15,431
Life on which depreciation in latest income statements is computed	25 years 9 months
Greenwich Avenue
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	7,484
Initial cost to company, Buildings and Improvements	5,444
Cost Capitalized Subsequent to Acquisition	1,041
Gross amount at which carried at close of period, Land	7,484
Gross amount at which carried at close of period, Buildings and Improvements	6,485
Gross amount at which carried at close of period, Total	13,969
Accumulated Depreciation and Amortization	3,590
Life on which depreciation in latest income statements is computed	35 years
Hauppauge
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	13,566
Initial cost to company, Land	8,791
Initial cost to company, Buildings and Improvements	15,262
Cost Capitalized Subsequent to Acquisition	4,060
Gross amount at which carried at close of period, Land	8,426
Gross amount at which carried at close of period, Buildings and Improvements	19,687
Gross amount at which carried at close of period, Total	28,113
Accumulated Depreciation and Amortization	9,591
Life on which depreciation in latest income statements is computed	35 years
Hermosa Avenue
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,116
Initial cost to company, Buildings and Improvements	280
Cost Capitalized Subsequent to Acquisition	4,485
Gross amount at which carried at close of period, Land	1,368
Gross amount at which carried at close of period, Buildings and Improvements	4,513
Gross amount at which carried at close of period, Total	5,881
Accumulated Depreciation and Amortization	2,365
Life on which depreciation in latest income statements is computed	35 years
Hollywood Blvd.
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	8,300
Initial cost to company, Buildings and Improvements	16,920
Cost Capitalized Subsequent to Acquisition	21,729
Gross amount at which carried at close of period, Land	8,300
Gross amount at which carried at close of period, Buildings and Improvements	38,649
Gross amount at which carried at close of period, Total	46,949
Accumulated Depreciation and Amortization	10,619
Life on which depreciation in latest income statements is computed	35 years
Houston Street
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	14,680
Initial cost to company, Buildings and Improvements	1,976
Cost Capitalized Subsequent to Acquisition	45,419
Gross amount at which carried at close of period, Land	14,778
Gross amount at which carried at close of period, Buildings and Improvements	47,297
Gross amount at which carried at close of period, Total	62,075
Accumulated Depreciation and Amortization	27,915
Life on which depreciation in latest income statements is computed	35 years
Huntington
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	11,713
Initial cost to company, Buildings and Improvements	16,008
Cost Capitalized Subsequent to Acquisition	16,042
Gross amount at which carried at close of period, Land	11,713
Gross amount at which carried at close of period, Buildings and Improvements	32,050
Gross amount at which carried at close of period, Total	43,763
Accumulated Depreciation and Amortization	12,121
Life on which depreciation in latest income statements is computed	35 years
Huntington Square
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	0
Initial cost to company, Buildings and Improvements	10,075
Cost Capitalized Subsequent to Acquisition	2,307
Gross amount at which carried at close of period, Land	0
Gross amount at which carried at close of period, Buildings and Improvements	12,382
Gross amount at which carried at close of period, Total	12,382
Accumulated Depreciation and Amortization	1,717
Life on which depreciation in latest income statements is computed	35 years
Idylwood Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	4,308
Initial cost to company, Buildings and Improvements	10,026
Cost Capitalized Subsequent to Acquisition	2,390
Gross amount at which carried at close of period, Land	4,308
Gross amount at which carried at close of period, Buildings and Improvements	12,416
Gross amount at which carried at close of period, Total	16,724
Accumulated Depreciation and Amortization	7,553
Life on which depreciation in latest income statements is computed	35 years
Kings Court
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	0
Initial cost to company, Buildings and Improvements	10,714
Cost Capitalized Subsequent to Acquisition	894
Gross amount at which carried at close of period, Land	0
Gross amount at which carried at close of period, Buildings and Improvements	11,608
Gross amount at which carried at close of period, Total	11,608
Accumulated Depreciation and Amortization	7,429
Life on which depreciation in latest income statements is computed	26 years
Lancaster
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	4,907
Initial cost to company, Land	0
Initial cost to company, Buildings and Improvements	2,103
Cost Capitalized Subsequent to Acquisition	11,441
Gross amount at which carried at close of period, Land	75
Gross amount at which carried at close of period, Buildings and Improvements	13,469
Gross amount at which carried at close of period, Total	13,544
Accumulated Depreciation and Amortization	7,341
Life on which depreciation in latest income statements is computed	22 years
Langhorne Square
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	720
Initial cost to company, Buildings and Improvements	2,974
Cost Capitalized Subsequent to Acquisition	18,082
Gross amount at which carried at close of period, Land	720
Gross amount at which carried at close of period, Buildings and Improvements	21,056
Gross amount at which carried at close of period, Total	21,776
Accumulated Depreciation and Amortization	12,997
Life on which depreciation in latest income statements is computed	35 years
Laurel
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	7,458
Initial cost to company, Buildings and Improvements	22,525
Cost Capitalized Subsequent to Acquisition	22,974
Gross amount at which carried at close of period, Land	7,464
Gross amount at which carried at close of period, Buildings and Improvements	45,493
Gross amount at which carried at close of period, Total	52,957
Accumulated Depreciation and Amortization	32,934
Life on which depreciation in latest income statements is computed	35 years
Lawrence Park
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	25,507
Initial cost to company, Land	5,723
Initial cost to company, Buildings and Improvements	7,160
Cost Capitalized Subsequent to Acquisition	19,078
Gross amount at which carried at close of period, Land	5,734
Gross amount at which carried at close of period, Buildings and Improvements	26,227
Gross amount at which carried at close of period, Total	31,961
Accumulated Depreciation and Amortization	23,109
Life on which depreciation in latest income statements is computed	22 years
Leesburg Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	8,184
Initial cost to company, Buildings and Improvements	10,722
Cost Capitalized Subsequent to Acquisition	16,729
Gross amount at which carried at close of period, Land	8,184
Gross amount at which carried at close of period, Buildings and Improvements	27,451
Gross amount at which carried at close of period, Total	35,635
Accumulated Depreciation and Amortization	12,093
Life on which depreciation in latest income statements is computed	35 years
Linden Square
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	79,382
Initial cost to company, Buildings and Improvements	19,247
Cost Capitalized Subsequent to Acquisition	48,105
Gross amount at which carried at close of period, Land	79,269
Gross amount at which carried at close of period, Buildings and Improvements	67,465
Gross amount at which carried at close of period, Total	146,734
Accumulated Depreciation and Amortization	15,329
Life on which depreciation in latest income statements is computed	35 years
Melville Mall
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	35,622
Initial cost to company, Buildings and Improvements	32,882
Cost Capitalized Subsequent to Acquisition	1,401
Gross amount at which carried at close of period, Land	35,622
Gross amount at which carried at close of period, Buildings and Improvements	34,283
Gross amount at which carried at close of period, Total	69,905
Accumulated Depreciation and Amortization	7,968
Life on which depreciation in latest income statements is computed	35 years
Mercer Mall
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	55,741
Initial cost to company, Land	28,684
Initial cost to company, Buildings and Improvements	48,028
Cost Capitalized Subsequent to Acquisition	39,012
Gross amount at which carried at close of period, Land	28,684
Gross amount at which carried at close of period, Buildings and Improvements	87,040
Gross amount at which carried at close of period, Total	115,724
Accumulated Depreciation and Amortization	30,786
Mercer Mall | Minimum
Real Estate and Accumulated Depreciation [Line Items]
Life on which depreciation in latest income statements is computed	25 years
Mercer Mall | Maximum
Real Estate and Accumulated Depreciation [Line Items]
Life on which depreciation in latest income statements is computed	35 years
Montrose Crossing
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	75,867
Initial cost to company, Land	48,624
Initial cost to company, Buildings and Improvements	91,819
Cost Capitalized Subsequent to Acquisition	12,663
Gross amount at which carried at close of period, Land	48,624
Gross amount at which carried at close of period, Buildings and Improvements	104,482
Gross amount at which carried at close of period, Total	153,106
Accumulated Depreciation and Amortization	12,524
Life on which depreciation in latest income statements is computed	35 years
Mount Vernon/South Valley/7770 Richmond Hwy,
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	10,068
Initial cost to company, Buildings and Improvements	33,501
Cost Capitalized Subsequent to Acquisition	38,701
Gross amount at which carried at close of period, Land	10,230
Gross amount at which carried at close of period, Buildings and Improvements	72,040
Gross amount at which carried at close of period, Total	82,270
Accumulated Depreciation and Amortization	25,865
Life on which depreciation in latest income statements is computed	35 years
Town Center of New Britain
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,282
Initial cost to company, Buildings and Improvements	12,285
Cost Capitalized Subsequent to Acquisition	1,064
Gross amount at which carried at close of period, Land	1,341
Gross amount at which carried at close of period, Buildings and Improvements	13,290
Gross amount at which carried at close of period, Total	14,631
Accumulated Depreciation and Amortization	3,752
Life on which depreciation in latest income statements is computed	35 years
North Dartmouth
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	9,366
Initial cost to company, Buildings and Improvements	0
Cost Capitalized Subsequent to Acquisition	2
Gross amount at which carried at close of period, Land	9,366
Gross amount at which carried at close of period, Buildings and Improvements	2
Gross amount at which carried at close of period, Total	9,368
Accumulated Depreciation and Amortization	2
Life on which depreciation in latest income statements is computed
Northeast
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,152
Initial cost to company, Buildings and Improvements	10,596
Cost Capitalized Subsequent to Acquisition	13,116
Gross amount at which carried at close of period, Land	1,153
Gross amount at which carried at close of period, Buildings and Improvements	23,711
Gross amount at which carried at close of period, Total	24,864
Accumulated Depreciation and Amortization	18,127
Life on which depreciation in latest income statements is computed	35 years
North Lake Commons
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	2,782
Initial cost to company, Buildings and Improvements	8,604
Cost Capitalized Subsequent to Acquisition	5,184
Gross amount at which carried at close of period, Land	2,628
Gross amount at which carried at close of period, Buildings and Improvements	13,942
Gross amount at which carried at close of period, Total	16,570
Accumulated Depreciation and Amortization	7,064
Life on which depreciation in latest income statements is computed	35 years
Old Keene Mill
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	638
Initial cost to company, Buildings and Improvements	998
Cost Capitalized Subsequent to Acquisition	4,744
Gross amount at which carried at close of period, Land	638
Gross amount at which carried at close of period, Buildings and Improvements	5,742
Gross amount at which carried at close of period, Total	6,380
Accumulated Depreciation and Amortization	4,870
Life on which depreciation in latest income statements is computed	33 years 4 months
Old Town Center
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,420
Initial cost to company, Buildings and Improvements	2,765
Cost Capitalized Subsequent to Acquisition	31,637
Gross amount at which carried at close of period, Land	3,420
Gross amount at which carried at close of period, Buildings and Improvements	34,402
Gross amount at which carried at close of period, Total	37,822
Accumulated Depreciation and Amortization	19,398
Life on which depreciation in latest income statements is computed	35 years
Pan Am Shopping Center
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	8,694
Initial cost to company, Buildings and Improvements	12,929
Cost Capitalized Subsequent to Acquisition	7,178
Gross amount at which carried at close of period, Land	8,695
Gross amount at which carried at close of period, Buildings and Improvements	20,106
Gross amount at which carried at close of period, Total	28,801
Accumulated Depreciation and Amortization	13,321
Life on which depreciation in latest income statements is computed	35 years
Pentagon Row
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	0
Initial cost to company, Buildings and Improvements	2,955
Cost Capitalized Subsequent to Acquisition	95,525
Gross amount at which carried at close of period, Land	0
Gross amount at which carried at close of period, Buildings and Improvements	98,480
Gross amount at which carried at close of period, Total	98,480
Accumulated Depreciation and Amortization	39,074
Life on which depreciation in latest income statements is computed	35 years
Perring Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	2,800
Initial cost to company, Buildings and Improvements	6,461
Cost Capitalized Subsequent to Acquisition	20,575
Gross amount at which carried at close of period, Land	2,800
Gross amount at which carried at close of period, Buildings and Improvements	27,036
Gross amount at which carried at close of period, Total	29,836
Accumulated Depreciation and Amortization	20,605
Life on which depreciation in latest income statements is computed	35 years
Pike & Rose
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	31,471
Initial cost to company, Buildings and Improvements	10,335
Cost Capitalized Subsequent to Acquisition	240,995
Gross amount at which carried at close of period, Land	26,201
Gross amount at which carried at close of period, Buildings and Improvements	256,600
Gross amount at which carried at close of period, Total	282,801
Accumulated Depreciation and Amortization	1,326
Life on which depreciation in latest income statements is computed	50 years
Pike 7
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	9,709
Initial cost to company, Buildings and Improvements	22,799
Cost Capitalized Subsequent to Acquisition	3,720
Gross amount at which carried at close of period, Land	9,653
Gross amount at which carried at close of period, Buildings and Improvements	26,575
Gross amount at which carried at close of period, Total	36,228
Accumulated Depreciation and Amortization	14,025
Life on which depreciation in latest income statements is computed	35 years
Plaza El Segundo
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	180,269
Initial cost to company, Land	62,127
Initial cost to company, Buildings and Improvements	153,556
Cost Capitalized Subsequent to Acquisition	36,876
Gross amount at which carried at close of period, Land	62,127
Gross amount at which carried at close of period, Buildings and Improvements	190,432
Gross amount at which carried at close of period, Total	252,559
Accumulated Depreciation and Amortization	18,186
Life on which depreciation in latest income statements is computed	35 years
Queen Anne Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,319
Initial cost to company, Buildings and Improvements	8,457
Cost Capitalized Subsequent to Acquisition	6,274
Gross amount at which carried at close of period, Land	3,319
Gross amount at which carried at close of period, Buildings and Improvements	14,731
Gross amount at which carried at close of period, Total	18,050
Accumulated Depreciation and Amortization	8,433
Life on which depreciation in latest income statements is computed	35 years
Quince Orchard Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,197
Initial cost to company, Buildings and Improvements	7,949
Cost Capitalized Subsequent to Acquisition	21,878
Gross amount at which carried at close of period, Land	2,928
Gross amount at which carried at close of period, Buildings and Improvements	30,096
Gross amount at which carried at close of period, Total	33,024
Accumulated Depreciation and Amortization	14,462
Life on which depreciation in latest income statements is computed	35 years
Rockville Town Square
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	4,508
Initial cost to company, Land	0
Initial cost to company, Buildings and Improvements	8,092
Cost Capitalized Subsequent to Acquisition	41,858
Gross amount at which carried at close of period, Land	0
Gross amount at which carried at close of period, Buildings and Improvements	49,950
Gross amount at which carried at close of period, Total	49,950
Accumulated Depreciation and Amortization	11,727
Life on which depreciation in latest income statements is computed	50 years
Rollingwood Apts.
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	22,130
Initial cost to company, Land	552
Initial cost to company, Buildings and Improvements	2,246
Cost Capitalized Subsequent to Acquisition	7,046
Gross amount at which carried at close of period, Land	572
Gross amount at which carried at close of period, Buildings and Improvements	9,272
Gross amount at which carried at close of period, Total	9,844
Accumulated Depreciation and Amortization	8,189
Life on which depreciation in latest income statements is computed	25 years
Sam's Park and Shop
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	4,840
Initial cost to company, Buildings and Improvements	6,319
Cost Capitalized Subsequent to Acquisition	1,338
Gross amount at which carried at close of period, Land	4,840
Gross amount at which carried at close of period, Buildings and Improvements	7,657
Gross amount at which carried at close of period, Total	12,497
Accumulated Depreciation and Amortization	4,364
Life on which depreciation in latest income statements is computed	35 years
Santana Row
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	66,682
Initial cost to company, Buildings and Improvements	7,502
Cost Capitalized Subsequent to Acquisition	619,379
Gross amount at which carried at close of period, Land	57,574
Gross amount at which carried at close of period, Buildings and Improvements	635,989
Gross amount at which carried at close of period, Total	693,563
Accumulated Depreciation and Amortization	135,085
Santana Row | Minimum
Real Estate and Accumulated Depreciation [Line Items]
Life on which depreciation in latest income statements is computed	40 years
Santana Row | Maximum
Real Estate and Accumulated Depreciation [Line Items]
Life on which depreciation in latest income statements is computed	50 years
Saugus
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	4,383
Initial cost to company, Buildings and Improvements	8,291
Cost Capitalized Subsequent to Acquisition	2,227
Gross amount at which carried at close of period, Land	4,383
Gross amount at which carried at close of period, Buildings and Improvements	10,518
Gross amount at which carried at close of period, Total	14,901
Accumulated Depreciation and Amortization	5,436
Life on which depreciation in latest income statements is computed	35 years
Shirlington
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	6,491
Initial cost to company, Land	9,761
Initial cost to company, Buildings and Improvements	14,808
Cost Capitalized Subsequent to Acquisition	35,364
Gross amount at which carried at close of period, Land	4,234
Gross amount at which carried at close of period, Buildings and Improvements	55,699
Gross amount at which carried at close of period, Total	59,933
Accumulated Depreciation and Amortization	20,957
Life on which depreciation in latest income statements is computed	35 years
The Grove at Shrewsbury
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	59,633
Initial cost to company, Land	18,016
Initial cost to company, Buildings and Improvements	103,115
Cost Capitalized Subsequent to Acquisition	406
Gross amount at which carried at close of period, Land	18,016
Gross amount at which carried at close of period, Buildings and Improvements	103,521
Gross amount at which carried at close of period, Total	121,537
Accumulated Depreciation and Amortization	3,507
Life on which depreciation in latest income statements is computed	35 years
The Shoppes At Nottingham Square
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	4,441
Initial cost to company, Buildings and Improvements	12,849
Cost Capitalized Subsequent to Acquisition	148
Gross amount at which carried at close of period, Land	4,441
Gross amount at which carried at close of period, Buildings and Improvements	12,997
Gross amount at which carried at close of period, Total	17,438
Accumulated Depreciation and Amortization	3,515
Life on which depreciation in latest income statements is computed	35 years
Third Street Promenade
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	22,645
Initial cost to company, Buildings and Improvements	12,709
Cost Capitalized Subsequent to Acquisition	42,994
Gross amount at which carried at close of period, Land	25,125
Gross amount at which carried at close of period, Buildings and Improvements	53,223
Gross amount at which carried at close of period, Total	78,348
Accumulated Depreciation and Amortization	28,315
Life on which depreciation in latest income statements is computed	35 years
Tower
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	7,170
Initial cost to company, Buildings and Improvements	10,518
Cost Capitalized Subsequent to Acquisition	3,715
Gross amount at which carried at close of period, Land	7,280
Gross amount at which carried at close of period, Buildings and Improvements	14,123
Gross amount at which carried at close of period, Total	21,403
Accumulated Depreciation and Amortization	7,396
Life on which depreciation in latest income statements is computed	35 years
Tower Shops
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	29,940
Initial cost to company, Buildings and Improvements	43,390
Cost Capitalized Subsequent to Acquisition	10,594
Gross amount at which carried at close of period, Land	29,962
Gross amount at which carried at close of period, Buildings and Improvements	53,962
Gross amount at which carried at close of period, Total	83,924
Accumulated Depreciation and Amortization	8,425
Life on which depreciation in latest income statements is computed	35 years
Troy
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,126
Initial cost to company, Buildings and Improvements	5,193
Cost Capitalized Subsequent to Acquisition	21,653
Gross amount at which carried at close of period, Land	4,028
Gross amount at which carried at close of period, Buildings and Improvements	25,944
Gross amount at which carried at close of period, Total	29,972
Accumulated Depreciation and Amortization	18,843
Life on which depreciation in latest income statements is computed	22 years
Tyson's Station
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	388
Initial cost to company, Buildings and Improvements	453
Cost Capitalized Subsequent to Acquisition	3,679
Gross amount at which carried at close of period, Land	475
Gross amount at which carried at close of period, Buildings and Improvements	4,045
Gross amount at which carried at close of period, Total	4,520
Accumulated Depreciation and Amortization	3,277
Life on which depreciation in latest income statements is computed	17 years
Westgate Center
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	6,319
Initial cost to company, Buildings and Improvements	107,284
Cost Capitalized Subsequent to Acquisition	28,278
Gross amount at which carried at close of period, Land	6,319
Gross amount at which carried at close of period, Buildings and Improvements	135,562
Gross amount at which carried at close of period, Total	141,881
Accumulated Depreciation and Amortization	31,731
Life on which depreciation in latest income statements is computed	35 years
White Marsh Plaza
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,478
Initial cost to company, Buildings and Improvements	21,413
Cost Capitalized Subsequent to Acquisition	248
Gross amount at which carried at close of period, Land	3,478
Gross amount at which carried at close of period, Buildings and Improvements	21,661
Gross amount at which carried at close of period, Total	25,139
Accumulated Depreciation and Amortization	6,307
Life on which depreciation in latest income statements is computed	35 years
White Marsh Other
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	34,281
Initial cost to company, Buildings and Improvements	1,843
Cost Capitalized Subsequent to Acquisition	402
Gross amount at which carried at close of period, Land	34,311
Gross amount at which carried at close of period, Buildings and Improvements	2,215
Gross amount at which carried at close of period, Total	36,526
Accumulated Depreciation and Amortization	591
Life on which depreciation in latest income statements is computed	35 years
Wildwood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	22,420
Initial cost to company, Land	9,111
Initial cost to company, Buildings and Improvements	1,061
Cost Capitalized Subsequent to Acquisition	8,354
Gross amount at which carried at close of period, Land	9,111
Gross amount at which carried at close of period, Buildings and Improvements	9,415
Gross amount at which carried at close of period, Total	18,526
Accumulated Depreciation and Amortization	7,946
Life on which depreciation in latest income statements is computed	33 years 4 months
Willow Grove
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	1,499
Initial cost to company, Buildings and Improvements	6,643
Cost Capitalized Subsequent to Acquisition	21,819
Gross amount at which carried at close of period, Land	1,499
Gross amount at which carried at close of period, Buildings and Improvements	28,462
Gross amount at which carried at close of period, Total	29,961
Accumulated Depreciation and Amortization	23,185
Life on which depreciation in latest income statements is computed	35 years
Willow Lawn
Real Estate and Accumulated Depreciation [Line Items]
Initial cost to company, Land	3,192
Initial cost to company, Buildings and Improvements	7,723
Cost Capitalized Subsequent to Acquisition	73,143
Gross amount at which carried at close of period, Land	7,790
Gross amount at which carried at close of period, Buildings and Improvements	76,268
Gross amount at which carried at close of period, Total	84,058
Accumulated Depreciation and Amortization	48,754
Life on which depreciation in latest income statements is computed	35 years
Wynnewood
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances	25,994
Initial cost to company, Land	8,055
Initial cost to company, Buildings and Improvements	13,759
Cost Capitalized Subsequent to Acquisition	18,808
Gross amount at which carried at close of period, Land	8,055
Gross amount at which carried at close of period, Buildings and Improvements	32,567
Gross amount at which carried at close of period, Total	40,622
Accumulated Depreciation and Amortization	$18,729
Life on which depreciation in latest income statements is computed	35 years

Schedule_III_Part_II_Summary_o1

Schedule III Part II - Summary of Real Estate and Accumulated Depreciation (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Aggregate cost basis for Federal tax purposes	$5,100,000,000
Real Estate and Accumulated Depreciation, Carrying Amount of Land and Buildings and Improvements [Abstract]
Balance at beginning of year	5,149,463,000	4,779,674,000	4,426,444,000
Acquisitions	174,328,000	76,359,000	193,131,000
Improvements	329,674,000	329,522,000	187,990,000
Deduction during period—disposition and retirements of property and transfer to joint venture	-44,467,000	-36,092,000	-27,891,000
Balance at end of year	5,608,998,000	5,149,463,000	4,779,674,000
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at beginning of year	1,350,471,000	1,224,295,000	1,127,588,000
Additions during period—depreciation and amortization expense	155,662,000	147,730,000	128,654,000
Deductions during period—disposition and retirements of property	-39,083,000	-21,554,000	-31,947,000
Balance at end of year	$1,467,050,000	$1,350,471,000	$1,224,295,000

Schedule_IV_Mortgage_Loans_on_1

Schedule IV - Mortgage Loans on Real Estate (Details) (USD $)	12 Months Ended				0 Months Ended
	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Aug. 04, 2006
Mortgage Loans on Real Estate [Line Items]
Prior Liens	$34,000,000
Face Amount of Mortgages	51,942,000
Carrying Amount of Mortgages	50,988,000	[1]	55,200,000
Principal Amount of Loans Subject to delinquent Principal or Interest	0
Mortgage Loans on Real Estate, Other Required Disclosures [Abstract]
Aggregate tax basis for Federal tax purposes	51,900,000
Interest rate	9.00%		9.00%
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of year	55,155,000		55,648,000	55,967,000
Issuance of loans				70,000
Collection and satisfaction of loans	-4,778,000		-1,057,000	-1,161,000
Amortization of discount	611,000		564,000	772,000
Balance at end of year	50,988,000		55,155,000	55,648,000
Mortgage On Retail Buildings in Philadelphia, PA, Loan One
Mortgage Loans on Real Estate [Line Items]
Prior Liens	0
Face Amount of Mortgages	20,286,000
Carrying Amount of Mortgages	20,286,000	[2]
Principal Amount of Loans Subject to delinquent Principal or Interest	0
Mortgage On Retail Buildings in Philadelphia, PA, Loan One | Interest Rate One
Mortgage Loans on Real Estate [Line Items]
Interest Rate	8.00%
Mortgage On Retail Buildings in Philadelphia, PA, Loan One | Interest Rate Two
Mortgage Loans on Real Estate [Line Items]
Interest Rate	10.00%
Mortgage On Retail Buildings in Philadelphia, PA, Loan One | Maximum
Mortgage Loans on Real Estate [Line Items]
Face Amount of Mortgages	25,000,000
Mortgage On Retail Buildings in Philadelphia, PA, Loan Two
Mortgage Loans on Real Estate [Line Items]
Prior Liens	0
Face Amount of Mortgages	9,250,000
Carrying Amount of Mortgages	9,250,000
Principal Amount of Loans Subject to delinquent Principal or Interest	0
Interest Rate	10.00%
Second Mortgage On Hotel In San Jose, CA
Mortgage Loans on Real Estate [Line Items]
Prior Liens	34,000,000	[3],[4]
Face Amount of Mortgages	10,691,000		11,900,000
Carrying Amount of Mortgages	9,737,000	[3]
Principal Amount of Loans Subject to delinquent Principal or Interest	0	[3]
Mortgage Loans on Real Estate, Other Required Disclosures [Abstract]
Interest rate	9.00%				14.00%
Amortization schedule, period					15 years
Mortgage loan on a shopping center and an adjacent commercial building in Norwalk ,CT
Mortgage Loans on Real Estate [Line Items]
Prior Liens	0
Face Amount of Mortgages	11,715,000
Carrying Amount of Mortgages	11,715,000
Principal Amount of Loans Subject to delinquent Principal or Interest	$0
Mortgage Loans on Real Estate, Other Required Disclosures [Abstract]
Interest rate	7.00%
[1]	For Federal tax purposes, the aggregate tax basis is approximately $51.9 million as of December 31, 2014.
[2]	This mortgage is available for up to $25.0 million.
[3]	This note was amended on August 4, 2006. The amended note decreased the interest from 14% to 9% per annum, and requires monthly payments of principal and interest based on 15-year amortization schedule.
[4]	We do not hold the first mortgage loan on this property. Accordingly, the amount of the prior lien at December 31, 2014 is estimated.