Goodwill and Other Intangibles (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Amortizable Intangible Assets
Less: accumulated amortization	$ (211,590)	$ (168,840)
Indefinite Lived Intangible Assets Including Goodwill
Indefinite-lived intangible assets	703,999	354,183
Total intangible assets, gross	2,537,658	1,244,705
Total intangible assets, net	2,326,068	1,075,865
Amortizable Intangible Liabilities
Finite-lived intangible liabilities, gross	(181,344)	(123,835)
Less: accumulated amortization	15,314	12,344
Net amortizable intangible liabilities	(166,030)	(111,491)
Indefinite Lived Intangible Liabilities
Total intangible liabilities, gross	(198,055)	(140,546)
Total intangible liabilities, net	182,741	128,202
Below-market purchase options
Indefinite Lived Intangible Liabilities
Indefinite-lived intangible liabilities	(16,711)	(16,711)
Below-market rent
Amortizable Intangible Liabilities
Finite-lived intangible liabilities, gross	(167,707)	(116,939)
Less: accumulated amortization	14,656	11,832
Net amortizable intangible liabilities	(153,051)	(105,107)
Above-market ground lease
Amortizable Intangible Liabilities
Finite-lived intangible liabilities, gross	(13,637)	(6,896)
Less: accumulated amortization	658	512
Net amortizable intangible liabilities	(12,979)	(6,384)
Goodwill
Indefinite Lived Intangible Assets Including Goodwill
Indefinite-lived intangible assets	700,024	350,208
Trade name
Indefinite Lived Intangible Assets Including Goodwill
Indefinite-lived intangible assets	3,975	3,975
Contracts including internal software development costs
Amortizable Intangible Assets
Finite lived intangible assets, gross	38,370	36,020
Less: accumulated amortization	(32,765)	(32,395)
Amortizable intangible assets	5,605	3,625
Management contracts
Amortizable Intangible Assets
Finite lived intangible assets, gross	32,765	32,765
Less: accumulated amortization	(32,765)	(32,395)
Amortizable intangible assets	0	370
Internal-use software development costs
Amortizable Intangible Assets
Finite lived intangible assets, gross	5,605	3,255
Less: accumulated amortization	0	0
Amortizable intangible assets	5,605	3,255
Lease intangibles
Amortizable Intangible Assets
Finite lived intangible assets, gross	1,795,289	854,502
Less: accumulated amortization	(178,825)	(136,445)
Amortizable intangible assets	1,616,464	718,057
In-place lease
Amortizable Intangible Assets
Finite lived intangible assets, gross	1,108,344	551,737
Less: accumulated amortization	(110,824)	(84,610)
Amortizable intangible assets	997,520	467,127
Tenant relationship
Amortizable Intangible Assets
Finite lived intangible assets, gross	6,246	6,247
Less: accumulated amortization	(1,698)	(1,656)
Amortizable intangible assets	4,548	4,591
Above-market rent
Amortizable Intangible Assets
Finite lived intangible assets, gross	661,624	292,132
Less: accumulated amortization	(66,194)	(50,157)
Amortizable intangible assets	595,430	241,975
Below-market ground lease
Amortizable Intangible Assets
Finite lived intangible assets, gross	19,075	4,386
Less: accumulated amortization	(109)	(22)
Amortizable intangible assets	$ 18,966	$ 4,364