Other Assets and Other Liabilities (Details) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Other Assets [Abstract]
Lease intangible assets	$ 340,527,000	$ 116,993,000
Striaght-line rent assets	144,372,000	112,284,000
Investment management contracts	139,090,000	24,066,000
Prepaid assets	124,377,000	52,272,000
Value added tax and other tax receivables	107,943,000	72,289,000
Goodwill	32,760,000	32,760,000
Other	191,077,000	182,750,000
Disclosure of Other Liabilities [Abstract]
Deferred income taxes	593,106,000	90,471,000
Tenant security deposit	149,785,000	71,982,000
Value added tax and other tax liabilities	119,818,000	80,188,000
Unearned Rent	120,020,000	36,776,000
Deferred income	50,988,000	53,931,000
Lease intangible liability	39,709,000	737,000
Other	$ 166,496,000	$ 133,913,000