Loans and Allowance for Loan Losses - Changes in allowance (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Changes in the allowance
Beginning Balance	$ 31,572	$ 34,246
Loan charge-offs	(45)	(784)
Loan recoveries	186	296
Ending Balance	31,713	33,758
Unallocated
Changes in the allowance
Beginning Balance	1,180	1,378
Provision for loan losses	(723)	(555)
Ending Balance	457	823
Commercial
Changes in the allowance
Beginning Balance	22,084	24,968
Provision for loan losses	357	533
Loan charge-offs	(27)	(740)
Loan recoveries	137	173
Ending Balance	22,551	24,934
Commercial \| Commercial and industrial
Changes in the allowance
Beginning Balance	8,925	10,205
Provision for loan losses	771	316
Loan charge-offs	(27)	(204)
Loan recoveries	126	170
Ending Balance	9,795	10,487
Commercial \| Real estate construction
Changes in the allowance
Beginning Balance	783	658
Provision for loan losses	27	(60)
Ending Balance	810	598
Commercial \| Commercial real estate
Changes in the allowance
Beginning Balance	12,376	14,105
Provision for loan losses	(441)	277
Loan charge-offs		(536)
Loan recoveries	11	3
Ending Balance	11,946	13,849
Consumer
Changes in the allowance
Beginning Balance	8,308	7,900
Provision for loan losses	366	22
Loan charge-offs	(18)	(44)
Loan recoveries	49	123
Ending Balance	8,705	8,001
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning Balance	6,532	5,774
Provision for loan losses	129	273
Ending Balance	6,661	6,047
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning Balance	1,295	1,373
Provision for loan losses	92	(168)
Loan recoveries	13	83
Ending Balance	1,400	1,288
Consumer \| Other revolving and installment
Changes in the allowance
Beginning Balance	481	753
Provision for loan losses	145	(83)
Loan charge-offs	(18)	(44)
Loan recoveries	36	40
Ending Balance	$ 644	$ 666

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

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-SubTopic 10
-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
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 220
-Section S99
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-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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