Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Leases [Abstract]
Facility operating expense	$ 4,625
Facility lease expense	68,668	$ 80,400
Operating lease expense	73,293
Operating lease expense adjustment	4,383
Operating cash flows from operating leases	77,676
Non-cash recognition of right-of-use assets obtained in exchange for new operating lease obligations	1,358
Depreciation and amortization	11,678
Interest expense: financing lease obligations	16,743	$ 22,931
Financing lease expense	28,421
Financing cash flows from financing leases	5,453
Operating cash flows from financing leases	16,743
Total cash flows from financing leases	$ 22,196