Lease Accounting - Lessee, Other Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$ (13,423)
Operating cash flows from finance leases	(1,413)
Financing cash flows from finance leases	(5,838)
Right-of-use assets obtained in exchange for lease obligations
Operating leases	8,117	$ 0
Finance leases	$ 20,215	$ 5,564
Weighted-average remaining lease term (years)
Operating leases	6 years 4 months 24 days
Finance leases	4 years 9 months 18 days
Weighted-average discount rate
Operating leases	4.10%
Finance leases	5.70%