Intangible Assets and Below Market Lease Liabilities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, accumulated amortization	$ (102,430)		$ (102,430)		$ (92,220)
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	218,022		218,022		222,211
Deferred Financing Costs [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, gross	19,567		19,567		17,363
Deferred financing and leasing costs, accumulated amortization	(6,434)		(6,434)		(5,204)
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	13,133		13,133		12,159
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	799	948	1,451	1,897
Deferred Leasing Costs [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, gross	300,885		300,885		297,068
Deferred financing and leasing costs, accumulated amortization	(95,996)		(95,996)		(87,016)
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	204,889		204,889		210,052
Deferred Leasing Costs and Acquisition-Related Intangible Assets [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	178,386		178,386
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	10,050	7,888	19,978	15,963
Lease Incentives [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	6,929		6,929
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	399	340	750	716
Acquisition-Related Intangible Assets (in Rental and Other Revenues) [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	15,999		15,999
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	1,114	484	2,230	950
Acquisition-Related Intangible Assets (in Rental Property and Other Expenses) [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Deferred financing and leasing costs, net/Total scheduled future amortization of intangible assets	3,575		3,575
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	139	139	276	276
Acquisition-Related Below Market Lease Liabilities [Member]
Intangible assets and below market lease liabilities, net [Abstract]
Acquisition-related below market lease liabilities, gross	54,903		54,903		55,323
Acquisition-related below market lease liabilities, accumulated amortization	(11,080)		(11,080)		(8,478)
Acquisition-related below market lease liabilities, net	43,823		43,823		46,845
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of acquisition-related below market lease liabilities	$ (1,500)	$ (1,031)	$ (3,022)	$ (2,153)