Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Plant and equipment
Property and equipment, net	$ 2,710,652		$ 2,756,669
Decrease in property and equipment	46,000
Depreciation expense	55,900	$ 65,000
Interest capitalized in connection with major construction projects	0	0
Master Lease Agreement
Plant and equipment
Depreciation expense	23,300	$ 22,700
Land and improvements - non-leased
Plant and equipment
Property and equipment	294,716		294,695
Land and improvements - master lease
Plant and equipment
Property and equipment	424,700		424,700
Building and improvements - non-leased
Plant and equipment
Property and equipment	430,440		429,015
Buildings and improvements - master lease
Plant and equipment
Property and equipment	2,258,577		2,258,577
Furniture, Fixtures and Equipment
Plant and equipment
Property and equipment	1,381,443		1,385,889
Leasehold Improvements
Plant and equipment
Property and equipment	131,257		130,801
Construction in progress - non-leased
Plant and equipment
Property and equipment	17,345		15,617
Non-leased assets
Plant and equipment
Property and equipment	2,255,201		2,256,017
Less Accumulated depreciation	(1,367,370)		(1,345,147)
Property and equipment, net	887,831		910,870
Master lease assets
Plant and equipment
Property and equipment	2,683,277		2,683,277
Less Accumulated depreciation	(860,456)		(837,478)
Property and equipment, net	$ 1,822,821		$ 1,845,799