Loans and Allowance for Credit Losses - Credit Risk Profile of Association's Loan Portfolio Based on Risk Rating Category and Year of Origination (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Jun. 30, 2023
Financing Receivable, Recorded Investment [Line Items]
2024	$ 16,637	$ 56,417
2023	154,396	212,517
2022	187,994	99,138
2021	86,694	86,618
2020	81,420	29,700
Prior Years	123,540	109,934
Total loans	650,681	594,324
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	16,637	53,624
2023	154,249	212,452
2022	187,957	98,869
2021	86,272	84,506
2020	79,102	29,096
Prior Years	122,823	109,593
Total loans	647,040	588,140
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
2022	0
2021	77
Prior Years		335
Total loans	77	335
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	0	2,793
2023	147	65
2022	37	269
2021	345	2,112
2020	2,318	604
Prior Years	717	6
Total loans	3,564	5,849
One- to four-family [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	7,525	22,046
2023	40,994	56,060
2022	52,994	27,937
2021	25,162	18,529
2020	15,651	6,218
Prior Years	33,791	33,064
Total loans	176,117	163,854
One- to four-family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	7,525	22,032
2023	40,980	56,054
2022	52,989	27,843
2021	25,080	18,468
2020	15,651	5,996
Prior Years	33,618	32,729
Total loans	175,843	163,122
One- to four-family [Member] \| Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	77
Prior Years		335
Total loans	77	335
One- to four-family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024		14
2023	14	6
2022	5	94
2021	5	61
2020		222
Prior Years	173
Total loans	197	397
Multi-family [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	320	674
2023	10,385	37,826
2022	51,405	10,647
2021	20,350	14,399
2020	22,898	8,831
Prior Years	22,399	17,272
Total loans	127,757	89,649
Multi-family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	320	674
2023	10,385	37,826
2022	51,405	10,647
2021	20,350	14,399
2020	22,898	8,587
Prior Years	22,163	17,272
Total loans	127,521	89,405
Multi-family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2020		244
Prior Years	236
Total loans	236	244
Home equity lines of credit [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	334	982
2023	3,393	2,554
2022	1,936	1,301
2021	1,533	1,035
2020	895	789
Prior Years	1,511	1,405
Total loans	9,602	8,066
Home equity lines of credit [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	334	982
2023	3,393	2,554
2022	1,936	1,301
2021	1,533	1,035
2020	895	789
Prior Years	1,511	1,405
Total loans	9,602	8,066
Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	2,294	2,882
2023	35,753	29,188
2022	3,069	10,432
2021		8,471
Prior Years	226
Total loans	41,342	50,973
Construction [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	2,294	2,882
2023	35,753	29,188
2022	3,069	10,432
2021		8,471
Prior Years	226
Total loans	41,342	50,973
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	1,926	12,214
2023	24,432	63,645
2022	61,466	29,320
2021	28,048	33,364
2020	31,902	5,925
Prior Years	51,049	49,239
Total loans	198,823	193,707
Commercial [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	1,926	12,214
2023	24,432	63,645
2022	61,466	29,320
2021	27,898	32,502
2020	31,072	5,844
Prior Years	50,797	49,239
Total loans	197,591	192,764
Commercial [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	150	862
2020	830	81
Prior Years	252
Total loans	1,232	943
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	3,496	15,228
2023	36,240	20,063
2022	14,995	17,847
2021	10,631	9,986
2020	9,591	7,726
Prior Years	14,430	8,843
Total loans	89,383	79,693
Commercial [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	3,496	12,449
2023	36,107	20,004
2022	14,963	17,673
2021	10,441	8,797
2020	8,103	7,669
Prior Years	14,374	8,841
Total loans	87,484	75,433
Commercial [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024		2,779
2023	133	59
2022	32	174
2021	190	1,189
2020	1,488	57
Prior Years	56	2
Total loans	1,899	4,260
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	742	2,391
2023	3,199	3,181
2022	2,129	1,654
2021	970	834
2020	483	211
Prior Years	134	111
Total loans	7,657	8,382
Consumer [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	742	2,391
2023	3,199	3,181
2022	2,129	1,653
2021	970	834
2020	483	211
Prior Years	134	107
Total loans	$ 7,657	8,377
Consumer [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2022		1
Prior Years		4
Total loans		$ 5

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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