Loans and Allowance for Credit Losses - Changes in allowance (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Changes in the allowance
Beginning balance	$ 35,843	$ 31,146	$ 31,146
Provision for credit losses	799	269
Loan charge-offs	(205)	(257)	(613)
Loan recoveries	147	87
Ending balance	36,584	35,102	35,843
Provision (recovery) for off-balance sheet credit loss	(793)	230
Debt securities held-to-maturity credit loss (reversal)	(6)	51
Increase (Decrease) in allowance for credit loss	$ 700
Percentage of increase in ACL compared to previous year	2.10%
Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		3,857	3,857
Commercial and industrial and commercial real estate portfolio
Changes in the allowance
Increase (Decrease) in allowance for credit loss	$ 1,000
Commercial
Changes in the allowance
Beginning balance	27,902	23,431	23,431
Provision for credit losses	767	79
Loan charge-offs	(193)	(175)
Loan recoveries	134	67
Ending balance	28,610	25,113	27,902
Commercial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		1,711	1,711
Commercial \| Commercial and industrial
Changes in the allowance
Beginning balance	9,894	9,233	9,233
Provision for credit losses	122	(395)
Loan charge-offs	(164)	(175)	(436)
Loan recoveries	123	56
Ending balance	9,975	8,012	9,894
Commercial \| Commercial and industrial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		(707)	(707)
Commercial \| Real estate construction
Changes in the allowance
Beginning balance	6,111	1,437	1,437
Provision for credit losses	(189)	439
Ending balance	5,922	4,425	6,111
Commercial \| Real estate construction \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		2,549	2,549
Commercial \| Commercial real estate
Changes in the allowance
Beginning balance	11,897	12,761	12,761
Provision for credit losses	834	35
Loan charge-offs	(29)
Loan recoveries	11	11
Ending balance	12,713	12,676	11,897
Commercial \| Commercial real estate \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		(131)	(131)
Consumer
Changes in the allowance
Beginning balance	7,941	7,715	7,715
Provision for credit losses	32	190
Loan charge-offs	(12)	(82)
Loan recoveries	13	20
Ending balance	7,974	9,989	7,941
Consumer \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		2,146	2,146
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning balance	6,578	5,858	5,858
Provision for credit losses	63	187
Loan charge-offs			(49)
Loan recoveries		2
Ending balance	6,641	8,316	6,578
Consumer \| Residential \| Real estate first mortgage \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		2,269	2,269
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning balance	1,151	1,317	1,317
Provision for credit losses	(3)	121
Loan charge-offs		(77)	(77)
Loan recoveries		6
Ending balance	1,148	1,340	1,151
Consumer \| Residential \| Real estate junior lien \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		(27)	(27)
Consumer \| Other revolving and installment
Changes in the allowance
Beginning balance	212	540	540
Provision for credit losses	(28)	(118)
Loan charge-offs	(12)	(5)	(51)
Loan recoveries	13	12
Ending balance	$ 185	333	212
Consumer \| Other revolving and installment \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance		$ (96)	$ (96)

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

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

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
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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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, 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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- Definition

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
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

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-Topic 326
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

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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