Total number of rental property or properties acquired from unaffiliated third parties during the period.

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The total number of rental properties that the Company disposed of to unaffiliated parties during the period.

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The total number of rental properties that the Company disposed of to unaffiliated parties during the period.

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Total number of rental units associated with rental properties that the company disposed of to unaffiliated third parties during the period.

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The difference between the book value and the sale price of land parcels sold within the period.

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Carrying amount of land for a real estate project that has not yet been completed.

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The cash inflow from the sale of investment property.

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Total number of units associated with the property or properties acquired from unaffiliated third parties during the period.

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Real Estate Textuals Abstract.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d
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The current amount of expenditures for a real estate project that has not yet been completed.

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Gain (loss) after tax expense or benefit, not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group.

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Gross amount, at the balance sheet date, of long-lived, depreciable assets commonly used in offices and stores. Examples include desks, chairs, and store fixtures.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Carrying amount as of the balance sheet date of real estate held for productive use. This excludes land held for sale.

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Carrying amount of land available for development.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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Represents a total which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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The net book value of real estate property held for investment purposes.

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Real Estate (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Table of Real Estate Owned
Land	$ 4,161,358		$ 4,161,358		$ 4,110,275
Depreciable property:
Buildings and improvements	13,833,714		13,833,714		13,995,121
Furniture and Fixtures, Gross	1,212,536		1,212,536		1,231,391
Construction-in-progress	115,085		115,085		130,337
Land - Land held for development	214,495		214,495		235,247
Investment in real estate	19,537,188		19,537,188		19,702,371
Accumulated depreciation	(4,307,406)		(4,307,406)		(4,337,357)
Investment in real estate, net	15,229,782		15,229,782		15,365,014
Acquired Properties
Properties - acquired	7		7
Units - acquired			2,069
Purchase Price - acquired	573,853		573,853
Disposed Properties
Properties - disposed			38
Units - disposed			11,267
Sales Price - disposed			1,196,100
Real Estate (Textuals) [Abstract]
Net gain on sales of discontinued operations	(558,482)	(217)	682,236	60,253
Net gain on sales of land parcels	4,217		4,217
Projects under development [Member]
Depreciable property:
Land - Projects under development	26,766		26,766		28,260
Construction-in-progress	88,319		88,319		102,077
Land held for development [Member]
Depreciable property:
Construction-in-progress	36,174		36,174		36,782
Land - Land held for development	178,321		178,321		198,465
Rental Properties [Member]
Acquired Properties
Properties - acquired	7		7
Units - acquired			2,069
Purchase Price - acquired	549,253		549,253
Land Parcels (three) [Member]
Acquired Properties
Properties - acquired	0		0
Units - acquired			0
Purchase Price - acquired	12,850		12,850
Disposed Properties
Properties - disposed			0
Units - disposed			0
Sales Price - disposed			22,786
Other Properties [Member]
Acquired Properties
Properties - acquired	0		0
Units - acquired			0
Purchase Price - acquired	11,750		11,750
Consolidated Rental Properties [Member]
Disposed Properties
Properties - disposed			38
Units - disposed			11,267
Sales Price - disposed			$ 1,173,314