Identified Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets and Liabilities
Gross amount	$ 387,677		$ 400,061
Accumulated amortization	(203,668)		(207,330)
Net	184,009		192,731
Gross amount	586,969		586,969
Accumulated amortization	(335,798)		(323,183)
Net	251,171		$ 263,786
Below Market Leases Net Of Above Market Leases
Finite-Lived Intangible Assets and Liabilities
Amortization of Intangible Assets	11,459	$ 17,507
2018	44,346
2019	32,168
2020	23,343
2021	18,159
2022	15,009
Other Identified Intangible Assets
Finite-Lived Intangible Assets and Liabilities
Amortization of Intangible Assets	7,108	7,793
2018	20,059
2019	15,720
2020	12,275
2021	11,177
2022	9,395
Tenant Under Ground Leases
Finite-Lived Intangible Assets and Liabilities
Amortization of Intangible Assets	458	$ 458
2018	1,832
2019	1,832
2020	1,832
2021	1,832
2022	$ 1,832