Loans Receivable and Allowance for Credit Losses - Recorded investment in loans by credit quality indicator (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2025
Credit quality indicator by year of origination
Total	$ 368,253	$ 377,366
Real Estate Loans
Credit quality indicator by year of origination
Total	350,793	358,950
Real Estate Loans \| One-to-Four Family Mortgages
Credit quality indicator by year of origination
Year 1	10,209	4,364
Year 2	22,131	19,886
Year 3	40,741	22,644
Year 4	57,154	38,690
Year 5	47,008	52,647
Prior	155,416	187,543
Total	332,659	325,774
Real Estate Loans \| One-to-Four Family Mortgages \| Pass
Credit quality indicator by year of origination
Year 1	10,209	4,364
Year 2	22,131	19,886
Year 3	39,963	22,644
Year 4	55,912	38,297
Year 5	46,651	51,438
Prior	152,989	185,963
Total	327,855	322,592
Real Estate Loans \| One-to-Four Family Mortgages \| Special Mention
Credit quality indicator by year of origination
Year 3	778
Year 4	836	393
Year 5	357	467
Prior	1,877	1,071
Total	3,848	1,931
Real Estate Loans \| One-to-Four Family Mortgages \| Substandard
Credit quality indicator by year of origination
Year 4	406
Year 5		742
Prior	550	509
Total	956	1,251
Real Estate Loans \| Home Equity Lines of Credit
Credit quality indicator by year of origination
Year 1	378	437
Year 2	66	603
Year 3	82	65
Year 4		11
Prior	531	494
Revolving	6,895	8,481
Total	7,952	10,091
Current Period Gross Write-Offs
Current Period Gross Write-Offs, Revolving	3
Current Period Gross Write-Offs, Total	3
Real Estate Loans \| Home Equity Lines of Credit \| Pass
Credit quality indicator by year of origination
Year 1	378	437
Year 2	66	603
Year 3	82	65
Year 4		11
Prior	531	494
Revolving	6,819	8,406
Total	7,876	10,016
Real Estate Loans \| Home Equity Lines of Credit \| Special Mention
Credit quality indicator by year of origination
Revolving	76	75
Total	76	75
Real Estate Loans \| Construction and Land
Credit quality indicator by year of origination
Year 1	7,385	11,372
Year 2	1,360	412
Year 3	181	131
Year 4	400	56
Year 5	113	357
Prior	149	210
Total	9,588	12,538
Real Estate Loans \| Construction and Land \| Pass
Credit quality indicator by year of origination
Year 1	7,385	11,372
Year 2	1,360	412
Year 3	62	131
Year 4	400	56
Year 5	113	357
Prior	149	210
Total	9,469	12,538
Real Estate Loans \| Construction and Land \| Substandard
Credit quality indicator by year of origination
Year 3	119
Total	119
Real Estate Loans \| Commercial Real Estate
Credit quality indicator by year of origination
Year 1		8,110
Year 2		1,884
Year 3	495
Year 4		467
Prior	99	86
Total	594	10,547
Real Estate Loans \| Commercial Real Estate \| Pass
Credit quality indicator by year of origination
Year 1		8,110
Year 2		1,884
Year 3	495
Year 4		467
Prior	99	86
Total	594	10,547
Other Loans \| Commercial and Industrial
Credit quality indicator by year of origination
Year 1	5,119	4,025
Year 2	6,004	4,370
Year 3	2,638	3,615
Year 4		2,217
Total	13,761	14,227
Other Loans \| Commercial and Industrial \| Pass
Credit quality indicator by year of origination
Year 1	5,119	4,025
Year 2	6,004	4,370
Year 3	2,638	3,615
Year 4		2,217
Total	13,761	14,227
Other Loans \| Consumer
Credit quality indicator by year of origination
Year 1	3,002	1,330
Year 2	236	2,388
Year 3	55	166
Year 4	35	25
Year 5	71	31
Prior	300	249
Total	3,699	4,189
Other Loans \| Consumer \| Pass
Credit quality indicator by year of origination
Year 1	3,002	1,330
Year 2	236	2,388
Year 3	55	166
Year 4	35	25
Year 5	71	31
Prior	300	249
Total	$ 3,699	$ 4,189

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

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, before allowance for credit loss, of 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, of financing receivable that can be withdrawn, repaid, and redrawn.

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Amount, excluding accrued interest, of writeoff of financing receivable that can be withdrawn, repaid, and redrawn.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

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