Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lease costs
Operating lease cost	$ 30,469	$ 91,287
Short-term lease cost	851	2,437
Variable lease cost	550	1,652
Sublease income	(480)	(996)
Net lease costs	$ 31,390	$ 94,380