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Real Estate Textuals Abstract.

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The current amount of expenditures for a real estate project that has not yet been completed.

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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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Real Estate (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011 Store Customers Apartment State Property MilitaryHouse	Sep. 30, 2010	Sep. 30, 2011 Year Project Apartment Property Store Customers OptionPlan State MilitaryHouse	Sep. 30, 2010	Dec. 31, 2010
Table of Real Estate Owned
Land	$ 4,158,288		$ 4,158,288		$ 4,110,275
Depreciable property:
Buildings and improvements	13,822,345		13,822,345		13,995,121
Furniture, fixtures and equipment	1,233,225		1,233,225		1,231,391
Construction-in-progress	119,433		119,433		130,337
Land - Land held for development	205,476		205,476		235,247
Investment in real estate	19,538,767		19,538,767		19,702,371
Accumulated depreciation	(4,405,479)		(4,405,479)		(4,337,357)
Investment in real estate, net	15,133,288		15,133,288		15,365,014
Acquired Properties
Properties - acquired	10		10
Units - acquired			2,529
Purchase Price - acquired	731,948		731,948
Disposed Properties
Properties - disposed			45
Units - disposed			13,528
Sales Price - disposed			1,406,200
Real Estate (Textuals) [Abstract]
Net (gain) on sales of discontinued operations	76,864	9,285	(759,100)	(69,538)
Net gain (loss) on sales of land parcels		(1,161)	4,217	(1,161)
Projects under development [Member]
Depreciable property:
Land - Projects under development	26,772		26,772		28,260
Construction-in-progress	92,661		92,661		102,077
Land held for development [Member]
Depreciable property:
Construction-in-progress	43,121		43,121		36,782
Land - Land held for development	162,355		162,355		198,465
Rental Properties [Member]
Acquired Properties
Properties - acquired	10		10
Units - acquired			2,529
Purchase Price - acquired	701,748		701,748
Land Parcels (three) [Member]
Acquired Properties
Properties - acquired	0		0
Units - acquired			0
Purchase Price - acquired	18,450		18,450
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			45
Units - disposed			13,528
Sales Price - disposed			$ 1,383,414