Segment Information - Summary of NOI by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Information
Total revenues	$ 541,818	$ 511,087	$ 1,078,255	$ 1,019,145
Operating expenses	235,981	215,700	473,583	436,359
NOI - consolidated	305,837	295,387	604,672	582,786
Deduct: NOI attributable to noncontrolling interests in consolidated subsidiaries	(17,160)	(16,269)	(34,472)	(32,607)
Add: Our share of NOI from partially owned entities	65,752	67,016	133,265	133,113
NOI at share	354,429	346,134	703,465	683,292
Non-cash adjustments for straight-line rents, amortization of acquired below-market leases, net and other	(12,481)	(22,475)	(30,429)	(42,956)
NOI at share - cash basis	341,948	323,659	673,036	640,336
New York
Segment Information
Total revenues	458,552	436,862	907,036	863,101
Operating expenses	200,903	185,712	398,819	368,819
NOI - consolidated	257,649	251,150	508,217	494,282
Deduct: NOI attributable to noncontrolling interests in consolidated subsidiaries	(11,560)	(11,348)	(23,305)	(22,787)
Add: Our share of NOI from partially owned entities	49,778	46,386	99,551	91,848
NOI at share	295,867	286,188	584,463	563,343
Non-cash adjustments for straight-line rents, amortization of acquired below-market leases, net and other	(12,713)	(18,297)	(30,036)	(36,669)
NOI at share - cash basis	283,154	267,891	554,427	526,674
Other
Segment Information
Total revenues	83,266	74,225	171,219	156,044
Operating expenses	35,078	29,988	74,764	67,540
NOI - consolidated	48,188	44,237	96,455	88,504
Deduct: NOI attributable to noncontrolling interests in consolidated subsidiaries	(5,600)	(4,921)	(11,167)	(9,820)
Add: Our share of NOI from partially owned entities	15,974	20,630	33,714	41,265
NOI at share	58,562	59,946	119,002	119,949
Non-cash adjustments for straight-line rents, amortization of acquired below-market leases, net and other	232	(4,178)	(393)	(6,287)
NOI at share - cash basis	$ 58,794	$ 55,768	$ 118,609	$ 113,662