Loans Receivable and Allowance for Credit Losses - Recorded investment in loans by credit quality indicator (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Recorded investment in loans by credit quality indicator
Total	$ 367,305	$ 367,050
One-to-Four Family Mortgages
Recorded investment in loans by credit quality indicator
Year 1	1,004	12,000
Year 2	13,272	43,298
Year 3	44,806	61,336
Year 4	60,800	50,786
Year 5	50,300	28,836
Prior	166,224	140,800
Total	336,406	337,056
One-to-Four Family Mortgages \| Pass
Recorded investment in loans by credit quality indicator
Year 1	1,004	12,000
Year 2	13,272	42,225
Year 3	43,857	60,557
Year 4	60,026	50,786
Year 5	50,300	28,836
Prior	165,465	140,000
Total	333,924	334,404
One-to-Four Family Mortgages \| Special Mention
Recorded investment in loans by credit quality indicator
Year 2		1,073
Year 3	949	779
Year 4	774
Prior	547	647
Total	2,270	2,499
One-to-Four Family Mortgages \| Substandard
Recorded investment in loans by credit quality indicator
Prior	212	153
Total	212	153
Home Equity Loans / Lines of Credit
Recorded investment in loans by credit quality indicator
Year 1		20
Year 2	67	226
Year 3	177
Year 5		174
Prior	581	369
Revolving	7,179	7,761
Total	8,004	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		20
Year 2	67	226
Year 3	177
Year 5		174
Prior	581	369
Revolving	7,080	7,570
Total	7,905	8,359
Home Equity Loans / Lines of Credit \| Special Mention
Recorded investment in loans by credit quality indicator
Revolving	99	191
Total	99	191
Construction Loans
Recorded investment in loans by credit quality indicator
Year 1	642	4,987
Year 2	7,154	2,189
Year 3	185	414
Year 4	411	366
Year 5	288
Prior	167	172
Total	8,847	8,128
Construction Loans \| Pass
Recorded investment in loans by credit quality indicator
Year 1	642	4,987
Year 2	7,154	2,189
Year 3	66	414
Year 4	411	366
Year 5	288
Prior	167	172
Total	8,728	8,128
Construction Loans \| Special Mention
Recorded investment in loans by credit quality indicator
Year 3	119
Total	119
Consumer Loans
Recorded investment in loans by credit quality indicator
Year 1	150	386
Year 2	319	74
Year 3	68	39
Year 4	36	52
Year 5	47	36
Prior	350	326
Total	970	913
Consumer Loans \| Pass
Recorded investment in loans by credit quality indicator
Year 1	150	386
Year 2	319	74
Year 3	68	39
Year 4	36	52
Year 5	47	36
Prior	350	326
Total	970	913
Commercial loans
Recorded investment in loans by credit quality indicator
Year 1	1,319	7,568
Year 2	7,215	4,724
Year 3	4,436
Year 4	108
Prior		111
Total	13,078	12,403
Commercial loans \| Pass
Recorded investment in loans by credit quality indicator
Year 1	1,319	7,568
Year 2	7,215	4,724
Year 3	4,436
Year 4	108
Prior		111
Total	$ 13,078	$ 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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