Loans and Allowance for Loan Losses - Changes in allowance (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in the allowance
Beginning Balance	$ 34,246	$ 23,924	$ 22,174
Provision for loan losses	(3,500)	10,900	7,312
Loan charge-offs	(1,922)	(5,368)	(7,578)
Loan recoveries	2,748	4,790	2,016
Ending Balance	31,572	34,246	23,924
Unallocated
Changes in the allowance
Beginning Balance	1,378	2,192	1,177
Provision for loan losses	(198)	(814)	1,015
Ending Balance	1,180	1,378	2,192
Commercial
Changes in the allowance
Beginning Balance	24,968	19,261	18,656
Provision for loan losses	(3,600)	6,372	5,523
Loan charge-offs	(1,766)	(5,114)	(6,541)
Loan recoveries	2,482	4,449	1,623
Ending Balance	22,084	24,968	19,261
Commercial \| Commercial and industrial
Changes in the allowance
Beginning Balance	10,205	12,270	12,127
Provision for loan losses	(1,710)	(2,168)	5,213
Loan charge-offs	(1,230)	(4,249)	(6,540)
Loan recoveries	1,660	4,352	1,470
Ending Balance	8,925	10,205	12,270
Commercial \| Real estate construction
Changes in the allowance
Beginning Balance	658	303	250
Provision for loan losses	125	355	51
Loan charge-offs			(1)
Loan recoveries			3
Ending Balance	783	658	303
Commercial \| Commercial real estate
Changes in the allowance
Beginning Balance	14,105	6,688	6,279
Provision for loan losses	(2,015)	8,185	259
Loan charge-offs	(536)	(865)
Loan recoveries	822	97	150
Ending Balance	12,376	14,105	6,688
Consumer
Changes in the allowance
Beginning Balance	7,900	2,471	2,341
Provision for loan losses	298	5,342	774
Loan charge-offs	(156)	(254)	(1,037)
Loan recoveries	266	341	393
Ending Balance	8,308	7,900	2,471
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning Balance	5,774	1,448	1,156
Provision for loan losses	758	4,321	292
Loan recoveries		5
Ending Balance	6,532	5,774	1,448
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning Balance	1,373	671	805
Provision for loan losses	(201)	507	99
Loan charge-offs		(12)	(465)
Loan recoveries	123	207	232
Ending Balance	1,295	1,373	671
Consumer \| Other revolving and installment
Changes in the allowance
Beginning Balance	753	352	380
Provision for loan losses	(259)	514	383
Loan charge-offs	(156)	(242)	(572)
Loan recoveries	143	129	161
Ending Balance	$ 481	$ 753	$ 352

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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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

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-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-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
-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 942
-SubTopic 220
-Section S99
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-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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