Loans and Allowance for Credit Losses on Loans - Schedule of Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 23,832		$ 22,539	$ 22,983	$ 23,023
(Reversal) Provision	425	$ 500	422	1,275	(63)
(Charge-offs)	(6)		(10)	(29)	(32)
Recoveries	9		12	31	35
Ending balance	24,260	23,832	22,963	24,260	22,963
Commercial loans \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,831		1,699	1,794	1,709
(Reversal) Provision	(20)		265	16	248
(Charge-offs)	(4)		(9)	(7)	(9)
Recoveries	1		3	5	10
Ending balance	1,808	1,831	1,958	1,808	1,958
Commercial real estate loans \| Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,589		2,617	2,487	2,776
(Reversal) Provision	(59)		(81)	43	(240)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	2,530	2,589	2,536	2,530	2,536
Commercial real estate loans \| Commercial non-owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	13,201		12,439	12,676
(Reversal) Provision	423		299
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	13,624	13,201	12,738	13,624	12,738
Commercial real estate loans \| Commercial real estate, investor
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				12,676	12,739
(Reversal) Provision				948	(1)
(Charge-offs)				0	0
Recoveries				0	0
Ending balance	13,624		12,738	13,624	12,738
Commercial real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,942		1,737	1,937	1,653
(Reversal) Provision	68		38	56	106
(Charge-offs)	0		0	0	0
Recoveries	8		9	25	25
Ending balance	2,018	1,942	1,784	2,018	1,784
Residential loans \| Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	561		530	558	595
(Reversal) Provision	4		12	7	(53)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	565	561	542	565	542
Residential loans \| Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	599		585	595	644
(Reversal) Provision	6		5	10	(54)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	605	599	590	605	590
Consumer loans \| Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	940		733	868	621
(Reversal) Provision	13		83	104	217
(Charge-offs)	(2)		(1)	(22)	(23)
Recoveries	0		0	1	0
Ending balance	951	940	815	951	815
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,169		2,199	2,068	2,286
(Reversal) Provision	(10)		(199)	91	(286)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	$ 2,159	$ 2,169	$ 2,000	$ 2,159	$ 2,000

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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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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
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-SubTopic 20
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-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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