Loans and Allowance for Credit Losses on Loans - Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 22,983		$ 23,023
Provision (reversal)	350	$ 0	(485)
(Charge-offs)	(14)		(2)
Recoveries	11		11
Ending balance	23,330	22,983	22,547
Commercial loans \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,794		1,709
Provision (reversal)	147		72
(Charge-offs)	(3)		0
Recoveries	3		3
Ending balance	1,941	1,794	1,784
Commercial real estate loans \| Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,487		2,776
Provision (reversal)	153		(154)
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	2,640	2,487	2,622
Commercial real estate loans \| Commercial non-owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,676		12,739
Provision (reversal)	25		(438)
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	12,701	12,676	12,301
Commercial real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,937		1,653
Provision (reversal)	74		56
(Charge-offs)	0		0
Recoveries	8		8
Ending balance	2,019	1,937	1,717
Residential loans \| Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	558		595
Provision (reversal)	(20)		(46)
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	538	558	549
Residential loans \| Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	595		644
Provision (reversal)	(18)		(16)
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	577	595	628
Consumer loans \| Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	868		621
Provision (reversal)	25		22
(Charge-offs)	(11)		(2)
Recoveries	0		0
Ending balance	882	868	641
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,068		2,286
Provision (reversal)	(36)		19
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	$ 2,032	$ 2,068	$ 2,305

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

+ Details

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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