Loans and Allowance for Credit Losses - Categories of Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024	Jun. 30, 2024
Real estate loans
Total loans	$ 625,438	$ 639,886	$ 654,189
Unearned fees and discounts, net	(335)	(344)
Allowance for credit losses	6,491	6,627	7,472	$ 7,499
Loans, net	619,282	633,603
One- to four-family [Member]
Real estate loans
Total loans	181,617	178,979	176,334
Allowance for credit losses	1,552	1,475	1,628	1,774
Multi-family [Member]
Real estate loans
Total loans	118,318	126,127	125,906
Allowance for credit losses	1,360	1,513	1,762	1,764
Home equity lines of credit [Member]
Real estate loans
Total loans	10,359	10,487	9,927
Allowance for credit losses	136	144	147	148
Construction [Member]
Real estate loans
Total loans	20,015	22,927	30,839
Allowance for credit losses	180	206	278	337
Commercial Business [Member]
Real estate loans
Total loans	196,022	201,550	205,103
Allowance for credit losses	2,117	2,252	2,362	2,358
Commercial [Member]
Real estate loans
Total loans	93,243	93,961	98,894
Allowance for credit losses	1,091	985	1,236	1,053
Consumer [Member]
Real estate loans
Total loans	5,864	5,855	7,186
Allowance for credit losses	$ 55	$ 52	$ 59	$ 65

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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