Leases - Supplemental Cash Flow (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating cash flows from operating leases	$ 35,728
Operating cash flows from financing leases	17
Financing cash flows from finance leases	282
Right-of-use assets obtained in exchange for lease obligations as of January 1, 2019, operating leases	2,289
Right-of-use assets obtained in exchange for lease obligations as of January 1, 2019, finance leases	$ 0