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Allowance for Loan Credit Losses - Allowance for loan losses activity (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	$ 19,543	$ 20,208
Recoveries	2	2
Provision for (recovery of) credit losses	(1,064)	(2,339)
Ending balance	18,481	20,036
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance		2,165
Real Estate Loans | Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance	12,841	13,205
Provision for (recovery of) credit losses	(1,286)	2,187
Ending balance	11,555	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	1,787	2,860
Provision for (recovery of) credit losses	(90)	(1,148)
Ending balance	1,697	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	4,323	3,044
Provision for (recovery of) credit losses	319	(3,014)
Ending balance	4,642	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	495	456
Recoveries	2	2
Provision for (recovery of) credit losses	37	(360)
Ending balance	534	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	97	5
Provision for (recovery of) credit losses	(44)	(4)
Ending balance	$ 53	58
Consumer - Non-Real Estate | Consumer | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance		57
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance		638
Unallocated | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance		$ (638)

X

- 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: 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 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
-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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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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