Allowance for Loan Credit Losses - Allowance for loan losses activity (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	$ 20,208	$ 20,032
Charge-offs		(1)
Provision for (recovery of) credit losses	(774)
Ending Balance	0	20,031
Beginning Balance	20,208
Recoveries	1
Provision for (recovery of) credit losses	(755)
Ending balance	21,619
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	2,165
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	638	632
Provision for (recovery of) credit losses		(205)
Ending Balance		427
Beginning Balance	638
Unallocated \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	(638)
Real Estate Loans \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	3,044	2,769
Provision for (recovery of) credit losses		(12)
Ending Balance		2,757
Beginning Balance	3,044
Provision for (recovery of) credit losses	330
Ending balance	7,926
Real Estate Loans \| Residential Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	4,552
Real Estate Loans \| Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	13,205	13,091
Charge-offs		(1)
Provision for (recovery of) credit losses		(694)
Ending Balance		12,396
Beginning Balance	13,205
Provision for (recovery of) credit losses	(742)
Ending balance	9,814
Real Estate Loans \| Commercial Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	(2,649)
Real Estate Loans \| Construction and land development
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	2,860	2,824
Provision for (recovery of) credit losses		922
Ending Balance		3,746
Beginning Balance	2,860
Provision for (recovery of) credit losses	(139)
Ending balance	3,197
Real Estate Loans \| Construction and land development \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	476
Commercial - Non-Real Estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	456	711
Provision for (recovery of) credit losses		(11)
Ending Balance		700
Beginning Balance	456
Recoveries	1
Provision for (recovery of) credit losses	(148)
Ending balance	676
Commercial - Non-Real Estate \| Commercial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	367
Consumer - Non-Real Estate \| Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	5	5
Ending Balance		$ 5
Beginning Balance	5
Provision for (recovery of) credit losses	(56)
Ending balance	6
Consumer - Non-Real Estate \| Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	$ 57

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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
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-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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+ References

No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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
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-Name Accounting Standards Codification
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-SubTopic 10
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Amount of expense related to estimated loss from loan and lease transactions.

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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.

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