Intangible Assets and Below Market Lease Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Assets:
Deferred leasing costs (including lease incentives and above market lease and in-place lease acquisition-related intangible assets)	$ 353,000		$ 353,000		$ 353,581
Deferred leasing costs, accumulated amortization	(147,744)		(147,744)		(140,081)
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	205,256		205,256		213,500
Liabilities (in accounts payable, accrued expenses and other liabilities):
Acquisition-related below market lease liabilities, gross	60,809		60,809		61,221
Acquisition-related below market lease liabilities, accumulated amortization	(25,834)		(25,834)		(23,074)
Acquisition-related below market lease liabilities, net	34,975		34,975		$ 38,147
Deferred Leasing Costs and Acquisition-Related Intangible Assets (in Depreciation and Amortization) [Member]
Assets:
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	186,928		186,928
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	10,133	$ 11,731	20,752	$ 23,066
Lease Incentives (in Rental and Other Revenues) [Member]
Assets:
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	8,818		8,818
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	443	390	840	1,101
Acquisition-Related Intangible Assets (in Rental and Other Revenues) [Member]
Assets:
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	7,605		7,605
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	675	972	1,711	2,003
Acquisition-Related Intangible Assets (in Rental Property and Other Expenses) [Member]
Assets:
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	1,905		1,905
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of intangible assets	139	139	276	277
Acquisition-Related Below Market Lease Liabilities (in Rental and Other Revenues) [Member]
Liabilities (in accounts payable, accrued expenses and other liabilities):
Acquisition-related below market lease liabilities, net	34,975		34,975
Amortization of intangible assets and below market lease liabilities [Abstract]
Amortization of acquisition-related below market lease liabilities	$ (1,592)	$ (2,788)	$ (3,172)	$ (4,560)