Leases - Net Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Lessee, Lease, Description [Line Items]
Net lease costs	$ (3,023)	$ (2,602)	$ (9,703)	$ (8,724)
Variable lease costs	400	400	900	1,100
Occupancy
Lessee, Lease, Description [Line Items]
Operating lease costs	(4,561)	(4,140)	(14,315)	(13,333)
Other non-interest income
Lessee, Lease, Description [Line Items]
Sublease revenue	$ 1,538	$ 1,538	$ 4,612	$ 4,609