Loans Receivable and Allowance for Credit Losses - Recorded investment in loans by credit quality indicator (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Credit quality indicator by year of origination
Total	$ 394,327	$ 377,366
Real Estate Loans
Credit quality indicator by year of origination
Total	370,524	358,950
Real Estate Loans \| One-to-Four Family Mortgages
Credit quality indicator by year of origination
Year 1	3,873	4,364
Year 2	7,431	19,886
Year 3	19,583	22,644
Year 4	21,888	38,690
Year 5	37,090	52,647
Prior	231,462	187,543
Total	321,327	325,774
Real Estate Loans \| One-to-Four Family Mortgages \| Pass
Credit quality indicator by year of origination
Year 1	3,873	4,364
Year 2	7,431	19,886
Year 3	19,583	22,644
Year 4	21,888	38,297
Year 5	36,701	51,438
Prior	228,979	185,963
Total	318,455	322,592
Real Estate Loans \| One-to-Four Family Mortgages \| Special Mention
Credit quality indicator by year of origination
Year 4		393
Year 5	389	467
Prior	1,465	1,071
Total	1,854	1,931
Real Estate Loans \| One-to-Four Family Mortgages \| Substandard
Credit quality indicator by year of origination
Year 5		742
Prior	1,018	509
Total	1,018	1,251
Real Estate Loans \| Home Equity Lines of Credit
Credit quality indicator by year of origination
Year 1		437
Year 2	78	603
Year 3	603	65
Year 4		11
Year 5	9
Prior	378	494
Revolving	9,426	8,481
Total	10,494	10,091
Real Estate Loans \| Home Equity Lines of Credit \| Pass
Credit quality indicator by year of origination
Year 1		437
Year 2	78	603
Year 3	603	65
Year 4		11
Year 5	9
Prior	378	494
Revolving	9,340	8,406
Total	10,408	10,016
Real Estate Loans \| Home Equity Lines of Credit \| Special Mention
Credit quality indicator by year of origination
Revolving	56	75
Total	56	75
Real Estate Loans \| Home Equity Lines of Credit \| Substandard
Credit quality indicator by year of origination
Revolving	30
Total	30
Real Estate Loans \| Construction and Land
Credit quality indicator by year of origination
Year 1	6,558	11,372
Year 2	15,374	412
Year 3	9	131
Year 4	128	56
Year 5	35	357
Prior	520	210
Total	22,624	12,538
Real Estate Loans \| Construction and Land \| Pass
Credit quality indicator by year of origination
Year 1	6,558	11,372
Year 2	15,374	412
Year 3	9	131
Year 4	128	56
Year 5	35	357
Prior	520	210
Total	22,624	12,538
Real Estate Loans \| Commercial Real Estate
Credit quality indicator by year of origination
Year 1	6,251	8,110
Year 2	7,341	1,884
Year 3	1,954
Year 4		467
Year 5	453
Prior	80	86
Total	16,079	10,547
Real Estate Loans \| Commercial Real Estate \| Pass
Credit quality indicator by year of origination
Year 1	6,251	8,110
Year 2	7,341	1,884
Year 3	1,954
Year 4		467
Year 5	453
Prior	80	86
Total	16,079	10,547
Other Loans \| Commercial and Industrial
Credit quality indicator by year of origination
Year 1	4,116	4,025
Year 2	3,950	4,370
Year 3	3,765	3,615
Year 4	3,264	2,217
Year 5	1,836
Total	16,931	14,227
Other Loans \| Commercial and Industrial \| Pass
Credit quality indicator by year of origination
Year 1	4,116	4,025
Year 2	3,950	4,370
Year 3	3,765	3,615
Year 4	3,264	2,217
Year 5	1,836
Total	16,931	14,227
Other Loans \| Consumer
Credit quality indicator by year of origination
Year 1	3,168	1,330
Year 2	1,212	2,388
Year 3	2,006	166
Year 4	218	25
Year 5	22	31
Prior	246	249
Total	6,872	4,189
Other Loans \| Consumer \| Pass
Credit quality indicator by year of origination
Year 1	3,168	1,330
Year 2	1,212	2,388
Year 3	2,006	166
Year 4	218	25
Year 5	22	31
Prior	246	249
Total	$ 6,872	$ 4,189

Amortized cost excluding accrued interest, before allowance for credit loss, of 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

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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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
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

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