Leases - Lease Expense Components (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 10,120	$ 29,099
Short-term lease cost	370	1,214
Variable lease cost	903	2,683
Less: sublease income	(1,140)	(3,363)
Total lease cost, net	10,253	29,633
Cash paid for operating leases	11,514	32,752
Operating leases	$ 7,770	$ 7,770
Weighted-average remaining term (in years) - operating leases	6 years 1 month 24 days	6 years 1 month 24 days
Weighted-average discount rate - operating leases	3.15%	3.15%