Leases - Lease Expense Components (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 11,605	$ 9,462	$ 22,969	$ 18,980
Short-term lease cost	420	582	759	845
Variable lease cost	1,198	933	1,791	1,779
Less: sublease income	(155)	(1,115)	(1,287)	(2,223)
Total lease cost, net	13,068	9,862	24,232	19,381
Cash paid for operating leases	12,130	10,884	24,351	21,238
Operating leases	$ 18,850	$ 0	$ 40,463	$ 0
Weighted-average remaining term (in years) - operating leases	6 years		6 years		6 years 3 months 14 days
Weighted-average discount rate - operating leases	2.64%		2.64%		2.92%