Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Federal [Abstract]
Current	$ (12)	$ 49	$ 1,367
Deferred	(3,248)	95,259	182,371
Total Federal Tax Expense	(3,260)	95,308	183,738
State [Abstract]
Current	(2,118)	(3,099)	(2,433)
Deferred (included in Federal above)	0	0	0
Total State Tax Expense	(2,118)	(3,099)	(2,433)
Total	$ (5,378)	92,209	181,305
U.S. Federal statutory rate	35.00%
Tax benefit at U.S. statutory rate	$ 139,657	192,390	115,603
Credits	6,163	3,937	(2,222)
Valuation allowance	(142,862)	(111,797)	64,155
Goodwill Impairment	(10,789)	(7,856)	0
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount	(5,716)	0	0
Non-deductible transaction costs	0	0	(6,870)
Return to provision	(920)	(72)	716
State taxes, net of federal income tax	11,788	18,323	11,582
Meals and entertainment	(868)	(1,090)	(946)
Other, net	(1,831)	(1,626)	(713)
Deferred income tax assets [Abstract]
Operating loss carryforwards	319,948	282,075
Accrued expenses	109,283	144,691
Prepaid revenue	2,626	2,415
Deferred lease liability	93,358	94,105
Capital and financing lease obligations	862,038	872,002
Tax credits	49,550	40,974
Intangible Assets	20,272	22,522
Deferred gain on sale leaseback	4,233	5,661
Total gross deferred income tax asset	1,461,308	1,464,445
Valuation allowance	(264,305)	(121,602)
Net deferred income tax assets	1,197,003	1,342,843
Deferred income tax liabilities [Abstract]
Property, plant and equipment	(1,209,595)	(1,320,423)
Investment in unconsolidated ventures	(66,678)	(88,798)
Other	(1,376)	(2,673)
Total gross deferred income tax liability	(1,277,649)	(1,411,894)
Net deferred tax liability	(80,646)	(69,051)
Operating Loss Carryforwards [Line Items]
Deferred Income Tax Expense (Benefit)	3,248	(95,261)	(182,371)
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			64,200
Tax Credit Carryforward [Line Items]
Tax credits, valuation allowance	46,200	32,100
Net operating loss, limitation of utilization		92,800
Unrecognized tax benefits [Roll Forward]
Balance at beginning of period	30,236	30,195
Additions for tax positions related to the current year	0	0
Additions for tax positions related to prior years	30	50
Reductions for tax positions related to prior years	(1,106)	(9)
Balance at end of period	29,160	30,236	30,195
Total interest and penalties reserved		100
Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry-forwards	1,033,000	930,400
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carry forwards, valuation allowance	218,100	89,500
Emeritus [Member]
Tax Credit Carryforward [Line Items]
Net operating loss, limitation of utilization	53,900
Federal, State and Local [Member]
Operating Loss Carryforwards [Line Items]
Deferred Income Tax Expense (Benefit)			$ 94,100
Restricted Stock [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry-forwards	$ 126,700	$ 126,700