Loans and Allowance for Credit Losses - Credit Risk Profile of Association's Loan Portfolio Based on Risk Rating Category and Calendar Year of Origination (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Mar. 31, 2025	Jun. 30, 2024
Financing Receivable, Recorded Investment [Line Items]
2025	$ 23,326	$ 43,030
2024	94,107	142,910
2023	124,495	177,235
2022	144,853	85,294
2021	79,114	79,971
Prior Years	179,049	117,949
Total loans	644,944	646,389
Current period charge-offs 2023	(350)
Current period charge-offs Total	(350)
Current period recoveries 2023	220
Current period recoveries Total	220
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	23,305	43,030
2024	94,107	142,763
2023	121,041	177,183
2022	144,813	84,877
2021	77,873	78,062
Prior Years	173,700	117,237
Total loans	634,839	643,152
Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		72
2021	193
Total loans	193	72
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	21
2024		147
2023	3,454	52
2022	40	345
2021	1,048	1,909
Prior Years	5,349	712
Total loans	9,912	3,165
One- to Four-Family [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	5,275	14,790
2024	23,570	39,216
2023	36,665	51,267
2022	46,876	24,439
2021	21,249	15,455
Prior Years	42,508	32,096
Total loans	176,143	177,263
Current period recoveries Prior Years	1	3
Current period recoveries Total	1	3
One- to Four-Family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	5,275	14,790
2024	23,570	39,202
2023	36,665	51,262
2022	46,872	24,362
2021	21,188	15,455
Prior Years	42,107	31,926
Total loans	175,677	176,997
One- to Four-Family [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		72
2021	56
Total loans	56	72
One- to Four-Family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024		14
2023		5
2022	4	5
2021	5
Prior Years	401	170
Total loans	410	194
Multi-Family [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	534	573
2024	15,729	9,004
2023	10,517	51,279
2022	39,750	20,346
2021	19,968	22,728
Prior Years	37,504	22,101
Total loans	124,002	126,031
Multi-Family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	534	573
2024	15,729	9,004
2023	10,517	51,279
2022	39,750	20,346
2021	19,968	22,728
Prior Years	37,277	21,867
Total loans	123,775	125,797
Multi-Family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Prior Years	227	234
Total loans	227	234
Home Equity Line of Credit [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	367	1,629
2024	2,503	2,361
2023	2,042	1,874
2022	1,583	1,806
2021	1,449	795
Prior Years	2,070	1,394
Total loans	10,014	9,859
Home Equity Line of Credit [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	367	1,629
2024	2,503	2,361
2023	2,042	1,874
2022	1,583	1,806
2021	1,449	795
Prior Years	2,070	1,394
Total loans	10,014	9,859
Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	1,110	9,123
2024	13,899	21,043
2023	12,058	3,250
2022	123
Prior Years	23	292
Total loans	27,213	33,708
Construction [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	1,110	9,123
2024	13,899	21,043
2023	12,058	3,250
2022	123
Prior Years	23	292
Total loans	27,213	33,708
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	8,977	4,602
2024	14,799	29,665
2023	26,189	57,530
2022	51,061	27,772
2021	30,468	31,310
Prior Years	76,162	49,138
Total loans	207,656	200,017
Commercial Real Estate [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	8,977	4,602
2024	14,799	29,665
2023	26,189	57,530
2022	51,061	27,622
2021	29,485	30,489
Prior Years	74,865	48,886
Total loans	205,376	198,794
Commercial Real Estate [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	137
Total loans	137
Commercial Real Estate [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		150
2021	846	821
Prior Years	1,297	252
Total loans	2,143	1,223
Commercial Business [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	6,094	10,357
2024	21,693	38,986
2023	35,357	10,205
2022	4,431	10,088
2021	5,586	9,289
Prior Years	20,563	12,859
Total loans	93,724	91,784
Current period charge-offs 2023	(50)
Current period charge-offs Total	(50)
Current period recoveries 2023	50
Current period recoveries 2021		242
Current period recoveries Prior Years	61
Current period recoveries Total	111	242
Commercial Business [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	6,073	10,357
2024	21,693	38,853
2023	31,921	10,158
2022	4,395	9,898
2021	5,389	8,201
Prior Years	17,139	12,803
Total loans	86,610	90,270
Commercial Business [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	21
2024		133
2023	3,436	47
2022	36	190
2021	197	1,088
Prior Years	3,424	56
Total loans	7,114	1,514
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	969	1,956
2024	1,914	2,635
2023	1,667	1,830
2022	1,029	843
2021	394	394
Prior Years	219	69
Total loans	6,192	7,727
Current period charge-offs 2025	(21)	(48)
Current period charge-offs 2024	(41)
Current period charge-offs 2022	(1)	(1)
Current period charge-offs Total	(63)	(49)
Current period recoveries 2025	2	14
Current period recoveries 2024	13
Current period recoveries Total	15	14
Consumer [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	969	1,956
2024	1,914	2,635
2023	1,649	1,830
2022	1,029	843
2021	394	394
Prior Years	219	69
Total loans	6,174	$ 7,727
Consumer [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2023	18
Total loans	$ 18

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