Leases - Lease Expense and Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Leases [Abstract]
Operating lease costs	$ 36,300	$ 34,400
Finance lease costs:
Amortization of leased assets	12,000	9,300
Interest on lease liabilities	10,400	7,300
Total finance lease costs	22,400	16,600
Variable and short-term lease costs	8,300	6,000
Total lease costs	67,000	57,000
Operating cash outflows from operating leases	33,700	32,800
Operating cash outflows from finance leases	10,400	7,300
Financing cash outflows from finance leases	8,300	5,200
Right-of-use assets obtained in exchange for operating leases	37,500	5,000
Right-of-use assets obtained in exchange for finance leases	$ 8,500	$ 5,000