Commitments and Credit Risk (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Total commitments	$ 1,592,991	$ 1,546,495
Commitments to originate loans
Loss Contingencies [Line Items]
Total commitments	188,347	134,652
Standby letters of credit
Loss Contingencies [Line Items]
Total commitments	42,204	39,035
Lines of credit
Loss Contingencies [Line Items]
Total commitments	1,362,440	1,351,873
Future lease commitments
Loss Contingencies [Line Items]
Total commitments	$ 0	$ 20,935