Loans - Loan Categories Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Schedule of Loans by Loan Classification [Line Items]
Loan origination fees	$ 6,200		$ 7,500
Accrued interest receivable on loans	10,200		10,200
Fee income	30,695	$ 33,650
Financing receivable, average loan size	2,962,721		2,920,684
Commercial
Schedule of Loans by Loan Classification [Line Items]
Participation loans amount	44,000		62,600
Financing receivable, average loan size	2,595,894		2,574,807
Participations loans sold that are still serviced amount	60,200		66,700
SBA Paycheck Protection Program ("PPP")
Schedule of Loans by Loan Classification [Line Items]
Loan origination amount		717,200
Processing costs	26,200
Fee income	1,400	$ 4,900
Deferred income	1,000
Financing receivable, average loan size	32,153		71,502
SBA Paycheck Protection Program ("PPP") | Quarterly Average
Schedule of Loans by Loan Classification [Line Items]
Financing receivable, average loan size	147
Residential mortgages
Schedule of Loans by Loan Classification [Line Items]
Financing receivable, average loan size	280,507		256,940
Amount of loans serviced for others	$ 10,000		$ 10,400