Variable Interest Entities - Consolidated Assets and Liabilities of VIEs (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
ASSETS
Buildings and improvements	$ 12,841,242	$ 11,120,039
Development costs and construction in progress	678,146	692,336
Land	2,113,871	1,992,602
Accumulated depreciation and amortization	(2,846,260)	(2,771,922)
Net real estate	12,786,999	11,033,055
Accounts receivable, net	73,432	59,417
Cash and cash equivalents	730,957	144,232	$ 130,521
Restricted cash	105,684	40,425	$ 25,531
Intangible assets, net	537,555	331,693
Right-of-use asset, net	193,729	172,486
Other assets, net	750,510	646,491
Total assets	16,316,440	14,032,891
LIABILITIES AND EQUITY
Mortgage debt	487,532	276,907
Intangible liabilities, net	110,732	74,991
Lease liability	177,029	156,611
Accounts payable, accrued liabilities, and other liabilities	847,080	540,924
Deferred revenue	751,443	289,680
Total liabilities	8,647,719	7,365,417
VIEs
ASSETS
Buildings and improvements	2,992,626	3,236,105
Development costs and construction in progress	96,090	67,285
Land	447,759	526,576
Accumulated depreciation and amortization	(623,212)	(568,574)
Net real estate	2,913,263	3,261,392
Accounts receivable, net	9,937	11,986
Cash and cash equivalents	41,590	47,027
Restricted cash	14,168	13,596
Intangible assets, net	143,965	206,840
Right-of-use asset, net	91,834	92,664
Other assets, net	57,030	52,124
Total assets	3,271,787	3,685,629
LIABILITIES AND EQUITY
Mortgage debt	217,310	218,767
Intangible liabilities, net	18,289	39,545
Lease liability	91,332	90,875
Accounts payable, accrued liabilities, and other liabilities	108,103	122,832
Deferred revenue	91,113	96,985
Total liabilities	$ 526,147	$ 569,004