Leases - Lease cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Facility operating expense	$ 18,677
Facility lease expense	269,666	$ 303,294	$ 339,721
Operating lease expense	288,343
Operating lease expense adjustment	19,453
Changes in operating lease assets and liabilities for lessor capital expenditure reimbursements	(31,305)
Operating cash flows from operating leases	276,491
Non-cash recognition of right-of-use assets obtained in exchange for new operating lease obligations	28,846
Depreciation and amortization	46,646
Interest expense: financing lease obligations	66,353	$ 83,604	$ 140,664
Financing lease expense	112,999
Operating cash flows from financing leases	66,353
Financing cash flows from financing leases	22,242
Changes in financing lease assets and liabilities for lessor capital expenditure reimbursement	(3,504)
Total cash flows from financing leases	$ 85,091