Allowance for Loan Credit Losses - Allowance for loan losses activity (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	$ 20,208	$ 20,032
Charge-offs		(1)
Recoveries		1
Ending Balance	0	20,032
Beginning Balance	20,208
Recoveries	2
Provision for (recovery of) credit losses	(2,339)
Ending balance	20,036
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		(49)
Ending Balance		583
Beginning Balance	638
Unallocated \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	(638)
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		345
Ending Balance		13,435
Beginning Balance	13,205
Provision for (recovery of) credit losses	2,187
Ending balance	12,743
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		97
Ending Balance		2,921
Beginning Balance	2,860
Provision for (recovery of) credit losses	(1,148)
Ending balance	2,188
Real Estate Loans \| Construction and land development \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	476
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		(186)
Ending Balance		2,583
Beginning Balance	3,044
Provision for (recovery of) credit losses	(3,014)
Ending balance	4,582
Real Estate Loans \| Residential Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	4,552
Commercial - Non-Real Estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	456	711
Recoveries		1
Provision for (recovery of) credit losses		(208)
Ending Balance		504
Beginning Balance	456
Recoveries	2
Provision for (recovery of) credit losses	(360)
Ending balance	465
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
Provision for (recovery of) credit losses		1
Ending Balance		$ 6
Beginning Balance	5
Provision for (recovery of) credit losses	(4)
Ending balance	58
Consumer - Non-Real Estate \| Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	$ 57

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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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.

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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.

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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.

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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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