Loans and Allowance for Loan Credit Losses - Schedule of Allowance for Credit Losses by Portfolio Type (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Allowance for credit losses:
Balance, beginning of period	$ 4,337	$ 4,399	$ 4,319	$ 4,482	$ 4,482
Provision for (recapture of) loan credit losses	(131)	1	(113)	(82)
Loans charged-off	0	0	0	0
Recoveries collected	0	0	0	0
Balance, end of period	4,206	4,400	4,206	4,400	4,319
Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses:
Balance, beginning of period				0	0
Commercial real estate
Allowance for credit losses:
Balance, beginning of period	1,136	1,142	1,233	905	905
Provision for (recapture of) loan credit losses	(114)	(102)	(211)	5
Loans charged-off	0	0	0	0	0
Recoveries collected	0	0	0	0
Balance, end of period	1,022	1,040	1,022	1,040	1,233
Commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses:
Balance, beginning of period				130	130
Commercial
Allowance for credit losses:
Balance, beginning of period	167	239	189	573	573
Provision for (recapture of) loan credit losses	(3)	(48)	(25)	(401)
Loans charged-off	0	0	0	0	0
Recoveries collected	0	0	0	0
Balance, end of period	164	191	164	191	189
Commercial \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses:
Balance, beginning of period				19	19
Residential real estate closed-end
Allowance for credit losses:
Balance, beginning of period	2,756	2,793	2,668	2,650	2,650
Provision for (recapture of) loan credit losses	18	170	106	329
Loans charged-off	0	0	0	0	0
Recoveries collected	0	0	0	0
Balance, end of period	2,774	2,963	2,774	2,963	2,668
Residential real estate closed-end \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses:
Balance, beginning of period				(16)	(16)
Other consumer loans
Allowance for credit losses:
Balance, beginning of period	278	225	229	354	354
Provision for (recapture of) loan credit losses	(32)	(19)	17	(15)
Loans charged-off	0	0	0	0	0
Recoveries collected	0	0	0	0
Balance, end of period	$ 246	$ 206	$ 246	206	229
Other consumer loans \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses:
Balance, beginning of period				$ (133)	$ (133)

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

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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+ 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
-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, 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-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.

+ 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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