Loans and Allowance for Loan Losses - Changes in allowance (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Changes in the allowance
Beginning Balance	$ 31,373	$ 33,764	$ 31,572	$ 34,246
Provision for loan losses		(2,000)		(2,000)
Loan charge-offs	(747)	(793)	(1,466)	(1,899)
Loan recoveries	342	1,095	862	1,719
Ending Balance	30,968	32,066	30,968	32,066
Unallocated
Changes in the allowance
Beginning Balance	1,052	2,469	1,180	1,378
Provision for loan losses	(100)	(1,453)	(228)	(362)
Ending Balance	952	1,016	952	1,016
Commercial
Changes in the allowance
Beginning Balance	22,045	23,144	22,084	24,968
Provision for loan losses	868	(1,146)	1,255	(2,406)
Loan charge-offs	(672)	(747)	(1,336)	(1,760)
Loan recoveries	282	1,052	520	1,501
Ending Balance	22,523	22,303	22,523	22,303
Commercial \| Commercial and industrial
Changes in the allowance
Beginning Balance	10,333	9,620	8,925	10,205
Provision for loan losses	(845)	(825)	1,011	(1,378)
Loan charge-offs	(672)	(747)	(1,336)	(1,224)
Loan recoveries	105	1,052	321	1,497
Ending Balance	8,921	9,100	8,921	9,100
Commercial \| Real estate construction
Changes in the allowance
Beginning Balance	878	587	783	658
Provision for loan losses	378	92	473	21
Loan recoveries	76		76
Ending Balance	1,332	679	1,332	679
Commercial \| Commercial real estate
Changes in the allowance
Beginning Balance	10,834	12,937	12,376	14,105
Provision for loan losses	1,335	(413)	(229)	(1,049)
Loan charge-offs				(536)
Loan recoveries	101		123	4
Ending Balance	12,270	12,524	12,270	12,524
Consumer
Changes in the allowance
Beginning Balance	8,276	8,151	8,308	7,900
Provision for loan losses	(768)	599	(1,027)	768
Loan charge-offs	(75)	(46)	(130)	(139)
Loan recoveries	60	43	342	218
Ending Balance	7,493	8,747	7,493	8,747
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning Balance	6,175	6,176	6,532	5,774
Provision for loan losses	(584)	625	(941)	1,027
Ending Balance	5,591	6,801	5,591	6,801
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning Balance	1,467	1,401	1,295	1,373
Provision for loan losses	(109)	6	(151)	(63)
Loan recoveries	7	16	221	113
Ending Balance	1,365	1,423	1,365	1,423
Consumer \| Other revolving and installment
Changes in the allowance
Beginning Balance	634	574	481	753
Provision for loan losses	(75)	(32)	65	(196)
Loan charge-offs	(75)	(46)	(130)	(139)
Loan recoveries	53	27	121	105
Ending Balance	$ 537	$ 523	$ 537	$ 523

Amount of increase in allowance for credit loss on accounts receivable, from recovery.

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 http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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- Definition

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

+ References

No definition available.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=122038336&loc=d3e74567-122707

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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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