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Number of Real Estate Properties Sold During the period.

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After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Cash received for the sale of real estate that is not part of an investing activity during the current period.

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Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Dispositions (Details) (USD $)	3 Months Ended					12 Months Ended
Dispositions (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current Fiscal Year End Date						--12-31
Investments in real estate partnerships (note 4)		$ 358,849,000				$ 333,167,000	$ 358,849,000
Proceeds from sale of real estate investments						118,787,000	212,632,000	352,707,000
Provision for impairment						1,257,000us-gaap_ImpairmentOfRealEstate	6,000,000us-gaap_ImpairmentOfRealEstate	74,816,000us-gaap_ImpairmentOfRealEstate
Gain (Loss) on Sale of Properties						55,077,000us-gaap_GainLossOnSaleOfProperties	59,656,000us-gaap_GainLossOnSaleOfProperties	24,013,000us-gaap_GainLossOnSaleOfProperties
Revenues included in Discontinued Operations	133,280,000us-gaap_Revenues	126,005,000us-gaap_Revenues	120,317,000us-gaap_Revenues	122,307,000us-gaap_Revenues	120,378,000us-gaap_Revenues
Discontinued Operation, Tax Effect of Discontinued Operation						0	0	600,000
Discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Provision for impairment							0	54,500,000
Revenues included in Discontinued Operations							14,924,000	26,413,000
Operating Expenses							7,592,000	15,514,000
Discontinued Operation, Tax Effect of Discontinued Operation							0	(18,000)
Parent Company [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investments in real estate partnerships (note 4)		358,849,000				333,167,000	358,849,000
Proceeds from sale of real estate investments						118,787,000	212,632,000	352,707,000
Provision for impairment						1,257,000	6,000,000	20,316,000
Gain (Loss) on Sale of Properties						55,077,000	1,703,000	2,158,000
Revenues included in Discontinued Operations						537,898,000	489,007,000	473,929,000
Operating Expenses						353,348,000	324,687,000	307,493,000
Operating income (loss)						0	7,332,000	(43,583,000)
Operating Segments [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties Sold						11	12	20
Operating Segments [Member] \| Discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties Sold								5
Operating Segments [Member] \| Continuing operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties Sold								15
Land [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties Sold						6	10	7
BRE Throne Holdings LLC (BRET) [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investments in real estate partnerships (note 4)		0					0
Proceeds from Sale of Real Estate							321,000,000
Provision for impairment							$ 18,100,000