Variable Interest Entities - Consolidated Assets and Liabilities of VIEs (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
ASSETS
Buildings and improvements	$ 12,720,111	$ 11,120,039
Development costs and construction in progress	588,343	692,336
Land	2,114,024	1,992,602
Accumulated depreciation and amortization	(2,840,632)	(2,771,922)
Net real estate	12,581,846	11,033,055
Investments in and advances to unconsolidated joint ventures	479,900	825,515
Accounts receivable, net	85,037	59,417
Cash and cash equivalents	783,542	144,232	$ 120,117
Restricted cash	106,557	40,425	$ 26,535
Intangible assets, net	550,348	331,693
Right-of-use asset, net	171,843	172,486
Other assets, net	776,387	646,491
Total assets	16,072,679	14,032,891
LIABILITIES AND EQUITY
Mortgage debt	490,049	276,907
Intangible liabilities, net	72,137	74,991
Lease liability	156,808	156,611
Accounts payable, accrued liabilities, and other liabilities	31,724	36,369
Deferred revenue	753,432	289,680
Total liabilities	8,259,236	7,365,417
VIEs
ASSETS
Buildings and improvements	2,983,887	3,236,105
Development costs and construction in progress	90,536	67,285
Land	447,758	526,576
Accumulated depreciation and amortization	(594,085)	(568,574)
Net real estate	2,928,096	3,261,392
Accounts receivable, net	10,884	11,986
Cash and cash equivalents	44,880	47,027
Restricted cash	13,631	13,596
Intangible assets, net	159,272	206,840
Right-of-use asset, net	92,225	92,664
Other assets, net	60,343	52,124
Total assets	3,309,331	3,685,629
LIABILITIES AND EQUITY
Mortgage debt	218,027	218,767
Intangible liabilities, net	19,221	39,545
Lease liability	91,078	90,875
Accounts payable, accrued liabilities, and other liabilities	114,350	122,832
Deferred revenue	91,845	96,985
Total liabilities	$ 534,521	$ 569,004