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Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
Significant Accounting Policies (Details) $ in Thousands	Dec. 31, 2021 USD ($) segment shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Trust assets
Assets under care	$ 12,700,000	$ 10,200,000
Securities:
Accrued interest receivable for debt securities available for sale debt	11,400
Loan servicing and portfolio loans
Unpaid principal balances of loans serviced	1,800,000
Impairment charges	600
Goodwill
Goodwill impairment	0	0
Cash surrender value of bank owned life insurance
Accrued liability	5,500	5,600
Income taxes
Valuation allowance	0	0
Accruals for payments of interest and penalties	0	0
Stock-based employee compensation
Compensation expense recognized	$ 7,864	7,135	$ 3,997
Segment disclosure
Number of operating segments \| segment	3
RSU awards
Stock-based employee compensation
Number of shares of common stock per award \| shares	1
Compensation expense recognized	$ 5,809	6,493	3,249
DSU awards
Stock-based employee compensation
Number of shares of common stock per award \| shares	1
Requisite service periods	30 days
Vesting period	1 year
Compensation expense recognized	$ 962	565	$ 602
PSU awards
Stock-based employee compensation
Number of shares of common stock per award \| shares	1
Compensation expense recognized	$ 979	77
ESPP
Stock-based employee compensation
Percentage of fair market value	85.00%
Percentage of discount to market price	15.00%
Minimum \| RSU awards
Stock-based employee compensation
Requisite service periods	1 year
Maximum \| RSU awards
Stock-based employee compensation
Requisite service periods	5 years
Buildings and improvements \| Minimum
Premises and Equipment, net
Estimated Useful Life	3 years
Buildings and improvements \| Maximum
Premises and Equipment, net
Estimated Useful Life	40 years
Furniture and equipment \| Minimum
Premises and Equipment, net
Estimated Useful Life	3 years
Furniture and equipment \| Maximum
Premises and Equipment, net
Estimated Useful Life	10 years
PPP Loans
PPP loans outstanding	$ 76,900	451,500
PPP loans outstanding, amortized cost	75,000	446,400
Loans outstanding, fees received	20,100	25,400
Incurred incremental direct origination costs	4,200	5,100
Net Interest Income for Fees, Net of Deferred Cost	14,000	$ 15,200
Fees, net of deferred costs remaining to be recognized	$ 1,900
Percentage of Remaining Loan Maintains Government Guarantee	100.00%
Borrower loan forgiveness	$ 999,000
Forgiveness application amount	$ 7,100