Intangible assets and Goodwill (Details 3) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Amortizable Intangible Assets
Amortizable intangible assets	$ 659,124
Unamortizable Goodwill and Indefinite-Lived Intangible Assets
Goodwill	338,558	63,607
Trade name	3,975	3,975
Indefinite lived intangible assets net, including goodwill	342,533	67,582
Intangible assets and goodwill, net	1,092,228	125,957
Intangible Liabilities Net
Net intangible liabilities	107,281	4,973
Below-market rent
Intangible Liabilities Net
Amortized and unamortizable intangible liabilities gross	(85,086)	(6,455)
Less: accumulated depreciation	1,412
Net intangible liabilities	(90,570)	(4,973)
Below-market purchase option
Intangible Liabilities Net
Net intangible liabilities	(16,711)	0
Above-market ground lease
Intangible Liabilities Net
Amortized and unamortizable intangible liabilities gross	(6,896)	0
Tenant Lease
Amortizable Intangible Assets
Less: accumulated amortization	(21,612)	(27,253)
Amortizable intangible assets	747,935	55,782
Management contracts
Amortizable Intangible Assets
Finite lived intangible assets gross	32,765	32,765
Less: accumulated amortization	(31,005)	(30,172)
Amortizable intangible assets	1,760	2,593
In-place lease \| Tenant Lease
Amortizable Intangible Assets
Finite lived intangible assets gross	468,426	62,162
Above-market rent \| Tenant Lease
Amortizable Intangible Assets
Finite lived intangible assets gross	292,977	9,905
Tenant relationship \| Tenant Lease
Amortizable Intangible Assets
Finite lived intangible assets gross	$ 8,144	$ 10,968

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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