Loans Receivable and Allowance for Credit Losses - Recorded investment in loans by credit quality indicator (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2024	Dec. 31, 2023
Recorded investment in loans by credit quality indicator
Total	$ 368,813	$ 367,050
One-to-Four Family Mortgages
Recorded investment in loans by credit quality indicator
Year 1	4,997	12,000
Year 2	15,350	43,298
Year 3	42,886	61,336
Year 4	58,983	50,786
Year 5	48,898	28,836
Prior	163,130	140,800
Total	334,244	337,056
One-to-Four Family Mortgages \| Pass
Recorded investment in loans by credit quality indicator
Year 1	4,997	12,000
Year 2	15,350	42,225
Year 3	42,188	60,557
Year 4	58,209	50,786
Year 5	48,898	28,836
Prior	162,748	140,000
Total	332,390	334,404
One-to-Four Family Mortgages \| Special Mention
Recorded investment in loans by credit quality indicator
Year 2		1,073
Year 3	580	779
Year 4	774
Prior	382	647
Total	1,736	2,499
One-to-Four Family Mortgages \| Substandard
Recorded investment in loans by credit quality indicator
Year 3	118
Prior		153
Total	118	153
Home Equity Loans / Lines of Credit
Recorded investment in loans by credit quality indicator
Year 1	38	20
Year 2	66	226
Year 3	95
Year 5		174
Prior	490	369
Revolving	7,514	7,761
Total	8,203	8,550
Current period gross revolving write-offs	3
Current Period Gross Write-Offs	3
Home Equity Loans / Lines of Credit \| Pass
Recorded investment in loans by credit quality indicator
Year 1	38	20
Year 2	66	226
Year 3	95
Year 5		174
Prior	490	369
Revolving	7,514	7,570
Total	8,203	8,359
Home Equity Loans / Lines of Credit \| Special Mention
Recorded investment in loans by credit quality indicator
Revolving		191
Total		191
Construction Loans
Recorded investment in loans by credit quality indicator
Year 1	2,150	4,987
Year 2	7,081	2,189
Year 3	184	414
Year 4	408	366
Year 5	284
Prior	161	172
Total	10,268	8,128
Construction Loans \| Pass
Recorded investment in loans by credit quality indicator
Year 1	2,150	4,987
Year 2	7,081	2,189
Year 3	184	414
Year 4	408	366
Year 5	284
Prior	161	172
Total	10,268	8,128
Consumer Loans
Recorded investment in loans by credit quality indicator
Year 1	262	386
Year 2	305	74
Year 3	63	39
Year 4	36	52
Year 5	42	36
Prior	345	326
Total	1,053	913
Consumer Loans \| Pass
Recorded investment in loans by credit quality indicator
Year 1	262	386
Year 2	305	74
Year 3	63	39
Year 4	36	52
Year 5	42	36
Prior	345	326
Total	1,053	913
Commercial loans
Recorded investment in loans by credit quality indicator
Year 1	4,253	7,568
Year 2	6,656	4,724
Year 3	4,031
Prior		111
Revolving	105
Total	15,045	12,403
Commercial loans \| Pass
Recorded investment in loans by credit quality indicator
Year 1	4,253	7,568
Year 2	6,656	4,724
Year 3	4,031
Prior		111
Revolving	105
Total	$ 15,045	$ 12,403

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

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