Loans and Allowance for Credit Losses - Changes in allowance (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Changes in the allowance
Beginning balance	$ 31,146	$ 31,572	$ 34,246
Provision for credit losses	(225)		(3,500)
Loan charge-offs	(613)	(1,549)	(1,922)
Loan recoveries	1,678	1,123	2,748
Ending balance	35,843	31,146	31,572
Provision for off-balance sheet credit loss	2,200
Debt securities held-to-maturity credit loss	40
Increase (Decrease) in allowance for credit loss	$ 4,700
Percentage of increase in ACL compared to previous year	15.10%
Increase in reserve dur to elevated risk of credit loss	$ 840
Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	3,857
Ending balance		3,857
Commercial
Changes in the allowance
Beginning balance	23,431	22,806	25,811
Provision for credit losses	1,992	1,350	(3,721)
Loan charge-offs	(436)	(1,396)	(1,766)
Loan recoveries	1,204	671	2,482
Ending balance	27,902	23,431	22,806
Commercial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	1,711
Ending balance		1,711
Commercial \| Commercial and industrial
Changes in the allowance
Beginning balance	9,233	9,218	10,547
Provision for credit losses	645	950	(1,759)
Loan charge-offs	(436)	(1,396)	(1,230)
Loan recoveries	1,159	461	1,660
Ending balance	9,894	9,233	9,218
Commercial \| Commercial and industrial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	(707)
Ending balance		(707)
Commercial \| Real estate construction
Changes in the allowance
Beginning balance	1,437	810	690
Provision for credit losses	2,125	551	120
Loan recoveries		76
Ending balance	6,111	1,437	810
Commercial \| Real estate construction \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	2,549
Ending balance		2,549
Commercial \| Commercial real estate
Changes in the allowance
Beginning balance	12,761	12,778	14,574
Provision for credit losses	(778)	(151)	(2,082)
Loan charge-offs			(536)
Loan recoveries	45	134	822
Ending balance	11,897	12,761	12,778
Commercial \| Commercial real estate \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	(131)
Ending balance		(131)
Consumer
Changes in the allowance
Beginning balance	7,715	8,766	8,435
Provision for credit losses	(2,217)	(1,350)	221
Loan charge-offs	(177)	(153)	(156)
Loan recoveries	474	452	266
Ending balance	7,941	7,715	8,766
Consumer \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	2,146
Ending balance		2,146
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning balance	5,857	6,874	6,174
Provision for credit losses	(1,829)	(1,017)	700
Loan charge-offs	(49)
Loan recoveries	330
Ending balance	6,578	5,857	6,874
Consumer \| Residential \| Real estate first mortgage \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	2,269
Ending balance		2,269
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning balance	1,318	1,380	1,472
Provision for credit losses	(115)	(344)	(215)
Loan charge-offs	(77)
Loan recoveries	52	282	123
Ending balance	1,151	1,318	1,380
Consumer \| Residential \| Real estate junior lien \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	(27)
Ending balance		(27)
Consumer \| Other revolving and installment
Changes in the allowance
Beginning balance	540	512	789
Provision for credit losses	(273)	11	(264)
Loan charge-offs	(51)	(153)	(156)
Loan recoveries	92	170	143
Ending balance	212	540	$ 512
Consumer \| Other revolving and installment \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance	$ (96)
Ending balance		$ (96)

The amount of increase in reserve due to elevated risk of credit loss.

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The percentage of increase in amount excluding accrued interest, of allowance for credit loss on financing receivable.

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No definition available.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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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).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Publisher FASB
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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
-Topic 326
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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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
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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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.

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