Summary of Significant Accounting Policies - Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Intangible Assets
Unamortized below market leases included in accounts payable, accrued expenses, intangibles and deferred revenues	$ 116,100	$ 117,800
Estimated future amortization, and the increasing (decreasing) effect on below market minimum rents
2017	30,015
2018	24,345
2019	20,615
2020	15,950
2021	7,355
Thereafter	17,861
Lease intangibles assets, net	116,141
Estimated future amortization, and the increasing (decreasing) effect on minimum rents
2017	2,340
2018	995
2019	1,535
2020	1,014
2021	(2,496)
Thereafter	729
Lease intangibles assets, net	$ 4,117
In-place lease intangibles
Intangible Assets
Average life of in-place lease intangibles	2 years 9 months 18 days
Lease intangibles assets, gross	$ 395,713	431,712
Accumulated amortization	(242,698)	(243,493)
Lease intangibles assets, net	$ 153,015	188,219
Above and below market leases
Intangible Assets
Weighted average remaining life of intangible	3 years 3 months 18 days
Amount of amortization expenses	$ 5,400	13,600	$ 11,300
Above Market Leases
Intangible Assets
Lease intangibles assets, gross	254,581	183,625
Accumulated amortization	(142,557)	(116,262)
Lease intangibles assets, net	112,024	$ 67,363
Estimated future amortization, and the increasing (decreasing) effect on minimum rents
2017	(27,675)
2018	(23,350)
2019	(19,080)
2020	(14,936)
2021	(9,851)
Thereafter	(17,132)
Lease intangibles assets, net	$ (112,024)