Loans and Allowance for Loan Losses - Changes in allowance (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Changes in the allowance
Beginning balance	$ 31,146	$ 31,572
Provision for credit losses	269
Loan charge-offs	(257)	(45)
Loan recoveries	87	186
Ending balance	35,102	31,713
Provision for off-balance sheet credit loss	230
Debt securities held-to-maturity credit loss	51
Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	3,857
Unallocated
Changes in the allowance
Beginning balance	268	1,180
Provision for credit losses	(83)	(723)
Ending balance	901	457
Unallocated \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	716
Commercial
Changes in the allowance
Beginning balance	23,292	22,084
Provision for credit losses	134	357
Loan charge-offs	(175)	(27)
Loan recoveries	67	137
Ending balance	24,550	22,551
Commercial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	1,232
Commercial \| Commercial and industrial
Changes in the allowance
Beginning balance	9,158	8,925
Provision for credit losses	(377)	771
Loan charge-offs	(175)	(27)
Loan recoveries	56	126
Ending balance	7,800	9,795
Commercial \| Commercial and industrial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	(862)
Commercial \| Real estate construction
Changes in the allowance
Beginning balance	1,446	783
Provision for credit losses	442	27
Ending balance	4,406	810
Commercial \| Real estate construction \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	2,518
Commercial \| Commercial real estate
Changes in the allowance
Beginning balance	12,688	12,376
Provision for credit losses	69	(441)
Loan recoveries	11	11
Ending balance	12,344	11,946
Commercial \| Commercial real estate \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	(424)
Consumer
Changes in the allowance
Beginning balance	7,586	8,308
Provision for credit losses	218	366
Loan charge-offs	(82)	(18)
Loan recoveries	20	49
Ending balance	9,651	8,705
Consumer \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	1,909
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning balance	5,769	6,532
Provision for credit losses	209	129
Loan recoveries	2
Ending balance	8,060	6,661
Consumer \| Residential \| Real estate first mortgage \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	2,080
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning balance	1,289	1,295
Provision for credit losses	126	92
Loan charge-offs	(77)
Loan recoveries	6	13
Ending balance	1,277	1,400
Consumer \| Residential \| Real estate junior lien \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	(67)
Consumer \| Other revolving and installment
Changes in the allowance
Beginning balance	528	481
Provision for credit losses	(117)	145
Loan charge-offs	(5)	(18)
Loan recoveries	12	36
Ending balance	314	$ 644
Consumer \| Other revolving and installment \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	$ (104)

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

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Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ 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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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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+ References

No definition available.

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+ 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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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ 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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