Leases - Summary of Rent Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Leases [Abstract]
Operating lease costs	$ 8,610	$ 17,506
Short-term lease costs	322	1,003
Variable lease costs	172	184
Total rent expense	$ 9,104	$ 18,693