Real Estate (Tables)

9 Months Ended

Sep. 30, 2011

Real Estate [Abstract]

Summarize the carrying amounts for the Company's investment in real estate (at cost)

	September 30, 2011			December 31, 2010
Land	$	4,158,288		$	4,110,275
Depreciable property:
Buildings and improvements		13,822,345			13,995,121
Furniture, fixtures and equipment		1,233,225			1,231,391
Projects under development:
Land		26,772			28,260
Construction-in-progress		92,661			102,077
Land held for development:
Land		162,355			198,465
Construction-in-progress		43,121			36,782
Investment in real estate		19,538,767			19,702,371
Accumulated depreciation		(4,405,479	)		(4,337,357	)
Investment in real estate, net	$	15,133,288		$	15,365,014

Acquired Properties

	Properties		Apartment Units		Purchase Price
Rental Properties – Consolidated		10		2,529	$	701,748
Land Parcels (three) (1)		—		—		18,450
Other (2)		—		—		11,750
Total		10		2,529	$	731,948

(1) Includes entry into a long-term ground lease for a land parcel in New York City.

(2) Represents the acquisition of a 97,000 square foot commercial building adjacent to our Harbor Steps apartment property in downtown Seattle for potential redevelopment.

Disposed Properties

	Properties		Apartment Units		Sales Price
Rental Properties – Consolidated		45		13,528	$	1,383,414
Land Parcel (one) (1)		—		—		22,786
Total		45		13,528	$	1,406,200

(1) Represents the sale of a land parcel, on which the Company no longer planned to develop, in suburban Washington, D.C.