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, 2022	Mar. 31, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 22,547	$ 23,023	$ 19,958	$ 23,023	$ 22,874
(Reversal) Provision	0	(485)	(920)	(485)	(3,849)
Charge-offs	(20)		0	(22)	0
Recoveries	12		62	23	75
Ending balance	22,539	22,547	19,100	22,539	19,100
Commercial loans \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,784	1,709	1,654	1,709	2,530
(Reversal) Provision	(89)		(68)	(17)	(947)
Charge-offs	0		0	0	0
Recoveries	4		4	7	7
Ending balance	1,699	1,784	1,590	1,699	1,590
Commercial real estate loans \| Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,622	2,776	2,304	2,776	2,778
(Reversal) Provision	(5)		(267)	(159)	(741)
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	2,617	2,622	2,037	2,617	2,037
Commercial real estate loans \| Commercial investor-owned
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,301	12,739	10,856	12,739	12,682
(Reversal) Provision	138		(95)	(300)	(1,921)
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	12,439	12,301	10,761	12,439	10,761
Commercial real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,717	1,653	1,312	1,653	1,557
(Reversal) Provision	12		(178)	68	(433)
Charge-offs	0		0	0	0
Recoveries	8		8	16	18
Ending balance	1,737	1,717	1,142	1,737	1,142
Residential loans \| Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	549	595	520	595	738
(Reversal) Provision	(19)		(158)	(65)	(376)
Charge-offs	0		0	0	0
Recoveries	0		50	0	50
Ending balance	530	549	412	530	412
Residential loans \| Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	628	644	757	644	998
(Reversal) Provision	(43)		(144)	(59)	(385)
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	585	628	613	585	613
Consumer loans \| Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	641	621	255	621	291
(Reversal) Provision	112		(17)	134	(53)
Charge-offs	(20)		0	(22)	0
Recoveries	0		0	0	0
Ending balance	733	641	238	733	238
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,305	2,286	2,300	2,286	1,300
(Reversal) Provision	(106)		7	(87)	1,007
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	$ 2,199	$ 2,305	$ 2,307	$ 2,199	$ 2,307

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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