Loans - Summary of Bank's Loans by Risk Ratings (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
2025	$ 21,811	$ 12,774
2024	12,224	20,614
2023	19,912	34,347
2022	32,671	20,622
2021	19,326	20,089
Prior	71,601	62,341
Revolving Loans Amortized Cost	1,578	1,591
Total Amortized Cost	179,123	172,378
Loans And Leases Receivables Gross Carrying Amount	179,123	172,378
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	21,752	12,682
2024	12,134	20,510
2023	19,830	34,305
2022	32,644	20,564
2021	19,287	19,711
Prior	70,184	61,238
Revolving Loans Amortized Cost	1,578	1,591
Total Amortized Cost	177,409	170,601
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	0	0
2024	0	0
2023	0	0
2022	0	0
2021	0	355
Prior	1,352	1,035
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	1,352	1,390
Deferred Fees [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	59	92
2024	90	104
2023	82	42
2022	27	58
2021	39	23
Prior	65	68
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	362	387
1-4 family [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	18,256	10,045
2024	6,820	10,709
2023	10,515	28,969
2022	27,606	16,833
2021	15,776	17,888
Prior	63,300	53,188
Revolving Loans Amortized Cost	0	383
Total Amortized Cost	142,273	138,015
1-4 family [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	18,256	10,045
2024	6,820	10,709
2023	10,515	28,969
2022	27,606	16,833
2021	15,776	17,533
Prior	61,948	52,153
Revolving Loans Amortized Cost	0	383
Total Amortized Cost	140,921	136,625
1-4 family [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	0	0
2024	0	0
2023	0	0
2022	0	0
2021	0	355
Prior	1,352	1,035
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	1,352	1,390
Multi Family Residential Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	2,474	699
2024	688	0
2023	376	3,799
2022	4,075	2,259
2021	2,915	1,123
Prior	5,287	3,840
Revolving Loans Amortized Cost	547	346
Total Amortized Cost	16,362	12,066
Multi Family Residential Portfolio Segment [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	2,474	699
2024	688	0
2023	376	3,799
2022	4,075	2,259
2021	2,915	1,123
Prior	5,287	3,840
Revolving Loans Amortized Cost	547	346
Total Amortized Cost	16,362	12,066
Second Mortgages And Home Equity Lines Of Credit Residential Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	604	1,085
2024	1,487	765
2023	539	126
2022	51	212
2021	197	57
Prior	286	336
Revolving Loans Amortized Cost	1,031	791
Total Amortized Cost	4,195	3,372
Second Mortgages And Home Equity Lines Of Credit Residential Portfolio Segment [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	604	1,085
2024	1,487	765
2023	539	126
2022	51	212
2021	197	57
Prior	286	336
Revolving Loans Amortized Cost	1,031	791
Total Amortized Cost	4,195	3,372
Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	0	498
2024	2,859	8,654
2023	8,095	1,059
2022	647	910
2021	155	836
Prior	2,537	4,805
Revolving Loans Amortized Cost	0	71
Total Amortized Cost	14,293	16,833
Commercial Real Estate [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	0	498
2024	2,859	8,654
2023	8,095	1,059
2022	647	910
2021	155	836
Prior	2,537	4,805
Revolving Loans Amortized Cost	0	71
Total Amortized Cost	14,293	16,833
Consumer Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	32	32
2024	22	0
2023	0	0
2022	0	0
2021	0	13
Prior	27	20
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	81	65
Consumer Portfolio Segment [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	32	32
2024	22	0
2023	0	0
2022	0	0
2021	0	13
Prior	27	20
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	81	65
Home Improvement Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	386	323
2024	258	382
2023	305	352
2022	265	350
2021	244	149
Prior	99	84
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	1,557	1,640
Home Improvement Portfolio Segment [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2025	386	323
2024	258	382
2023	305	352
2022	265	350
2021	244	149
Prior	99	84
Revolving Loans Amortized Cost	0	0
Total Amortized Cost	$ 1,557	$ 1,640

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