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Loans and Allowance for Credit Losses on Loans - Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 23,023		$ 22,874
Provision (reversal)	(485)	$ 600	(2,929)
Charge-offs	(2)		0
Recoveries	11		13
Ending balance	22,547	23,023	19,958
Commercial loans | Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,709		2,530
Provision (reversal)	72		(880)
Charge-offs	0		0
Recoveries	3		4
Ending balance	1,784	1,709	1,654
Commercial real estate loans | Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,776		2,778
Provision (reversal)	(154)		(474)
Charge-offs	0		0
Recoveries	0		0
Ending balance	2,622	2,776	2,304
Commercial real estate loans | Commercial investor-owned
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,739		12,682
Provision (reversal)	(438)		(1,826)
Charge-offs	0		0
Recoveries	0		0
Ending balance	12,301	12,739	10,856
Commercial real estate loans | Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,653		1,557
Provision (reversal)	56		(254)
Charge-offs	0		0
Recoveries	8		9
Ending balance	1,717	1,653	1,312
Residential loans | Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	595		738
Provision (reversal)	(46)		(218)
Charge-offs	0		0
Recoveries	0		0
Ending balance	549	595	520
Residential loans | Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	644		998
Provision (reversal)	(16)		(241)
Charge-offs	0		0
Recoveries	0		0
Ending balance	628	644	757
Consumer loans | Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	621		291
Provision (reversal)	22		(36)
Charge-offs	(2)		0
Recoveries	0		0
Ending balance	641	621	255
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,286		1,300
Provision (reversal)	19		1,000
Charge-offs	0		0
Recoveries	0		0
Ending balance	$ 2,305	$ 2,286	$ 2,300

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- Definition

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Amount excluding accrued interest, of allowance for credit loss on financing receivable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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