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	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Recorded Investment [Line Items]
2025	$ 45,850	$ 43,030
2024	90,613	142,910
2023	119,598	177,235
2022	141,490	85,294
2021	76,629	79,971
Prior Years	165,706	117,949
Total loans	639,886	646,389
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	45,850	43,030
2024	90,613	142,763
2023	116,226	177,183
2022	141,484	84,877
2021	75,395	78,062
Prior Years	162,820	117,237
Total loans	632,388	643,152
Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		72
2021	186
Prior Years	40
Total loans	226	72
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024		147
2023	3,372	52
2022	6	345
2021	1,048	1,909
Prior Years	2,846	712
Total loans	7,272	3,165
One- to four-family [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	16,760	14,790
2024	23,826	39,216
2023	32,946	51,267
2022	45,176	24,439
2021	19,935	15,455
Prior Years	40,336	32,096
Total loans	178,979	177,263
Current period charge-offs Prior Years	(79)
Current period charge-offs Total	(79)
Current period recoveries Prior Years	2	3
Current period recoveries Total	2	3
One- to four-family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	16,760	14,790
2024	23,826	39,202
2023	32,946	51,262
2022	45,173	24,362
2021	19,879	15,455
Prior Years	40,102	31,926
Total loans	178,686	176,997
One- to four-family [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		72
2021	51
Prior Years	40
Total loans	91	72
One- to four-family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024		14
2023		5
2022	3	5
2021	5
Prior Years	194	170
Total loans	202	194
Multi-family [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	4,517	573
2024	15,648	9,004
2023	10,379	51,279
2022	39,148	20,346
2021	19,827	22,728
Prior Years	36,608	22,101
Total loans	126,127	126,031
Current period charge-offs 2024	(350)
Current period charge-offs Total	(350)
Current period recoveries 2024	220
Current period recoveries Total	220
Multi-family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	4,517	573
2024	15,648	9,004
2023	10,379	51,279
2022	39,148	20,346
2021	19,827	22,728
Prior Years	36,383	21,867
Total loans	125,902	125,797
Multi-family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Prior Years	225	234
Total loans	225	234
Home equity lines of credit [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	1,004	1,629
2024	2,884	2,361
2023	1,851	1,874
2022	1,616	1,806
2021	1,230	795
Prior Years	1,902	1,394
Total loans	10,487	9,859
Home equity lines of credit [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	1,004	1,629
2024	2,884	2,361
2023	1,851	1,874
2022	1,616	1,806
2021	1,230	795
Prior Years	1,902	1,394
Total loans	10,487	9,859
Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	2,165	9,123
2024	8,574	21,043
2023	12,062	3,250
2022	123
Prior Years	3	292
Total loans	22,927	33,708
Construction [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	2,165	9,123
2024	8,574	21,043
2023	12,062	3,250
2022	123
Prior Years	3	292
Total loans	22,927	33,708
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	9,649	4,602
2024	14,724	29,665
2023	26,490	57,530
2022	50,471	27,772
2021	29,927	31,310
Prior Years	70,289	49,138
Total loans	201,550	200,017
Commercial [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	9,649	4,602
2024	14,724	29,665
2023	26,490	57,530
2022	50,471	27,622
2021	28,946	30,489
Prior Years	69,788	48,886
Total loans	200,068	198,794
Commercial [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	135
Total loans	135
Commercial [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		150
2021	846	821
Prior Years	501	252
Total loans	1,347	1,223
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	10,266	10,357
2024	23,374	38,986
2023	34,423	10,205
2022	4,073	10,088
2021	5,406	9,289
Prior Years	16,419	12,859
Total loans	93,961	91,784
Current period charge-offs 2024	(50)
Current period charge-offs Total	(50)
Current period recoveries 2024	50
Current period recoveries 2021		242
Current period recoveries Prior Years	63
Current period recoveries Total	113	242
Commercial [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	10,266	10,357
2024	23,374	38,853
2023	31,068	10,158
2022	4,070	9,898
2021	5,209	8,201
Prior Years	14,493	12,803
Total loans	88,480	90,270
Commercial [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024		133
2023	3,355	47
2022	3	190
2021	197	1,088
Prior Years	1,926	56
Total loans	5,481	1,514
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	1,489	1,956
2024	1,583	2,635
2023	1,447	1,830
2022	883	843
2021	304	394
Prior Years	149	69
Total loans	5,855	7,727
Current period charge-offs 2025	(28)	(48)
Current period charge-offs 2024	(41)
Current period charge-offs 2022	(1)	(1)
Current period charge-offs Total	(70)	(49)
Current period recoveries 2025	7
Current period recoveries 2024	13
Current period recoveries Total	20	14
Consumer [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2025	1,489	1,956
2024	1,583	2,635
2023	1,430	1,830
2022	883	843
2021	304	394
Prior Years	149	69
Total loans	5,838	7,727
Consumer [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2023	17	$ 0
Total loans	$ 17

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