Loans and Allowance for Credit Losses on Loans - Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 23,330	$ 22,983	$ 22,547	$ 22,983	$ 23,023
(Reversal) Provision	500	350	0	850	(485)
(Charge-offs)	(9)		(20)	(23)	(22)
Recoveries	11		12	22	23
Ending balance	23,832	23,330	22,539	23,832	22,539
Commercial loans \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,941	1,794	1,784	1,794	1,709
(Reversal) Provision	(111)		(89)	36	(17)
(Charge-offs)	0		0	(3)	0
Recoveries	1		4	4	7
Ending balance	1,831	1,941	1,699	1,831	1,699
Commercial real estate loans \| Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,640	2,487	2,622	2,487	2,776
(Reversal) Provision	(51)		(5)	102	(159)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	2,589	2,640	2,617	2,589	2,617
Commercial real estate loans \| Commercial non-owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,701	12,676	12,301	12,676
(Reversal) Provision	500		138
(Charge-offs)	0		0
Recoveries	0		0
Ending balance	13,201	12,701	12,439	13,201	12,439
Commercial real estate loans \| Commercial real estate, investor
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		12,676		12,676	12,739
(Reversal) Provision				525	(300)
(Charge-offs)				0	0
Recoveries				0	0
Ending balance	13,201		12,439	13,201	12,439
Commercial real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,019	1,937	1,717	1,937	1,653
(Reversal) Provision	(86)		12	(12)	68
(Charge-offs)	0		0	0	0
Recoveries	9		8	17	16
Ending balance	1,942	2,019	1,737	1,942	1,737
Residential loans \| Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	538	558	549	558	595
(Reversal) Provision	23		(19)	3	(65)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	561	538	530	561	530
Residential loans \| Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	577	595	628	595	644
(Reversal) Provision	22		(43)	4	(59)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	599	577	585	599	585
Consumer loans \| Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	882	868	641	868	621
(Reversal) Provision	66		112	91	134
(Charge-offs)	(9)		(20)	(20)	(22)
Recoveries	1		0	1	0
Ending balance	940	882	733	940	733
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,032	2,068	2,305	2,068	2,286
(Reversal) Provision	137		(106)	101	(87)
(Charge-offs)	0		0	0	0
Recoveries	0		0	0	0
Ending balance	$ 2,169	$ 2,032	$ 2,199	$ 2,169	$ 2,199

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

+ 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
-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
-Topic 326
-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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