Leases - Components of Total Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Leases [Abstract]
Amortization of ROU assets	$ 72	$ 218
Interest on lease liabilities	47	148
Operating lease cost	9,096	25,019
Short-term lease cost	134	268
Variable lease cost	723	2,695
Sublease income	(779)	(2,465)
Total lease cost (included in net occupancy and equipment expense)	$ 9,293	$ 25,883