Loans and Allowance for Credit Losses on Loans - Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 22,539		$ 19,100	$ 23,023	$ 22,874
Provision (reversal)	422	$ 0	1,800	(63)	(2,049)
Initial allowance for PCD loans			1,505		1,505
Charge-offs	(10)		(2)	(32)	(2)
Recoveries	12		11	35	86
Ending balance	22,963	22,539	22,414	22,963	22,414
Commercial loans \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,699		1,590	1,709	2,530
Provision (reversal)	265		126	248	(821)
Initial allowance for PCD loans			405		405
Charge-offs	(9)		0	(9)	0
Recoveries	3		3	10	10
Ending balance	1,958	1,699	2,124	1,958	2,124
Commercial real estate loans \| Commercial owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,617		2,037	2,776	2,778
Provision (reversal)	(81)		(30)	(240)	(771)
Initial allowance for PCD loans			559		559
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	2,536	2,617	2,566	2,536	2,566
Commercial real estate loans \| Commercial investor-owned
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,439		10,761	12,739	12,682
Provision (reversal)	299		1,011	(1)	(910)
Initial allowance for PCD loans			533		533
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	12,738	12,439	12,305	12,738	12,305
Commercial real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,737		1,142	1,653	1,557
Provision (reversal)	38		77	106	(356)
Initial allowance for PCD loans			0		0
Charge-offs	0		0	0	0
Recoveries	9		8	25	26
Ending balance	1,784	1,737	1,227	1,784	1,227
Residential loans \| Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	530		412	595	738
Provision (reversal)	12		247	(53)	(129)
Initial allowance for PCD loans			0		0
Charge-offs	0		0	0	0
Recoveries	0		0	0	50
Ending balance	542	530	659	542	659
Residential loans \| Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	585		613	644	998
Provision (reversal)	5		4	(54)	(381)
Initial allowance for PCD loans			6		6
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	590	585	623	590	623
Consumer loans \| Installment and other consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	733		238	621	291
Provision (reversal)	83		384	217	331
Initial allowance for PCD loans			2		2
Charge-offs	(1)		(2)	(23)	(2)
Recoveries	0		0	0	0
Ending balance	815	733	622	815	622
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,199		2,307	2,286	1,300
Provision (reversal)	(199)		(19)	(286)	988
Initial allowance for PCD loans			0		0
Charge-offs	0		0	0	0
Recoveries	0		0	0	0
Ending balance	$ 2,000	$ 2,199	$ 2,288	$ 2,000	$ 2,288

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

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- Definition

Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

+ 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 (c)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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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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