CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows from Operating Activities
Net income (loss)	$ 81,945	$ (268,492)	$ (528,352)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Loss (gain) on debt modification and extinguishment, net	(10,896)	5,247	11,677
Depreciation and amortization, net	365,654	383,703	455,615
Asset impairment	107,308	49,266	489,893
Equity in (earnings) loss of unconsolidated ventures	2,107	4,544	8,804
Distributions from unconsolidated ventures from cumulative share of net earnings	766	3,472	2,896
Amortization of deferred gain	0	0	(4,358)
Amortization of entrance fees	(2,122)	(1,634)	(1,670)
Proceeds from deferred entrance fee revenue	734	3,544	3,218
Deferred income tax (benefit) provision	(5,840)	(2,654)	(52,367)
Operating lease expense adjustment	(136,276)	(19,453)	(17,218)
Loss (gain) on sale of assets, net	(374,532)	(7,245)	(293,246)
Loss (gain) on facility lease termination and modification, net	(2,303)	3,388	140,957
Non-cash stock-based compensation expense	20,747	23,026	26,067
Non-cash interest expense on financing lease obligations	0	0	10,894
Non-cash management contract termination gain	0	(969)	(8,724)
Other	(2,777)	(8,700)	(1,292)
Changes in operating assets and liabilities:
Accounts receivable, net	24,277	292	(4,964)
Prepaid expenses and other assets, net	24,707	55,873	26,762
Trade accounts payable and accrued expenses	27,294	(12,984)	(37,307)
Refundable fees and deferred revenue	62,614	(25,117)	(128)
Operating lease assets and liabilities for lessor capital expenditure reimbursements	22,242	31,305	10,400
Operating lease assets and liabilities for lease termination	0	0	(33,596)
Net cash provided by (used in) operating activities	205,649	216,412	203,961
Cash Flows from Investing Activities
Change in lease security deposits and lease acquisition deposits, net	3,569	(859)	1,163
Purchase of marketable securities	(378,269)	(186,224)	(14,823)
Sale and maturities of marketable securities	275,000	134,000	293,273
Capital expenditures, net of related payables	(185,871)	(304,092)	(225,473)
Acquisition of assets, net of related payables and cash received	(472,193)	(497)	(271,771)
Investment in unconsolidated ventures	(4,082)	(4,346)	(9,124)
Distributions received from unconsolidated ventures	0	9,635	12,850
Proceeds from sale of assets, net	331,316	92,735	499,807
Proceeds from notes receivable	5,419	34,109	1,580
Property insurance proceeds	0	0	1,292
Net cash provided by (used in) investing activities	(425,111)	(225,539)	288,774
Cash Flows from Financing Activities
Proceeds from debt	963,099	321,996	606,921
Repayment of debt and financing lease obligations	(538,859)	(427,923)	(896,744)
Proceeds from line of credit	166,381	0	200,000
Repayment of line of credit	(166,381)	0	(200,000)
Purchase of treasury stock, net of related payables	(18,123)	(23,955)	(4,256)
Payment of financing costs, net of related payables	(19,649)	(7,309)	(16,317)
Proceeds from refundable entrance fees, net of refunds	0	0	(422)
Payments for lease termination	0	0	(12,548)
Payments of employee taxes for withheld shares	(4,037)	(3,313)	(3,061)
Other	482	1,110	1,364
Net cash provided by (used in) financing activities	382,913	(139,394)	(325,063)
Net increase (decrease) in cash, cash equivalents, and restricted cash	163,451	(148,521)	167,672
Cash, cash equivalents, and restricted cash at beginning of period	301,697	450,218	282,546
Cash, cash equivalents, and restricted cash at end of period	$ 465,148	$ 301,697	$ 450,218