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Loans and Allowance for Credit Losses - Allowance for Credit Losses (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Jun. 30, 2025
Allowance for loan losses: |  |  |
Balance, beginning of period | $ 6,627 | $ 7,499 | $ 7,499
Provision (credit) charged to expense | (65) | 377 | (678)
Losses charged off | (79) | (409) | (549)
Recoveries | 8 | 5 | 355
Balance, end of period | 6,491 | 7,472 | 6,627
Loans: |  |  |
Ending balance | 625,438 | 654,189 | 639,886
One- to Four-Family [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 1,475 | 1,774 | 1,774
Provision (credit) charged to expense | 75 | (147) | (222)
Losses charged off | 0 | 0 | (79)
Recoveries | 2 | 1 | 2
Balance, end of period | 1,552 | 1,628 | 1,475
Loans: |  |  |
Ending balance | 181,617 | 176,334 | 178,979
Multi-Family [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 1,513 | 1,764 | 1,764
Provision (credit) charged to expense | (153) | 348 | (121)
Losses charged off | 0 | (350) | (350)
Recoveries | 0 | 0 | 220
Balance, end of period | 1,360 | 1,762 | 1,513
Loans: |  |  |
Ending balance | 118,318 | 125,906 | 126,127
Home Equity Line of Credit [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 144 | 148 | 148
Provision (credit) charged to expense | (8) | (1) | (4)
Losses charged off | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 136 | 147 | 144
Loans: |  |  |
Ending balance | 10,359 | 9,927 | 10,487
Construction [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 206 | 337 | 337
Provision (credit) charged to expense | (26) | (59) | (131)
Losses charged off | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 180 | 278 | 206
Loans: |  |  |
Ending balance | 20,015 | 30,839 | 22,927
Commercial [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 2,252 | 2,358 | 2,358
Provision (credit) charged to expense | (135) | 4 | (106)
Losses charged off | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 2,117 | 2,362 | 2,252
Loans: |  |  |
Ending balance | 196,022 | 205,103 | 201,550
Commercial [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 985 | 1,053 | 1,053
Provision (credit) charged to expense | 174 | 231 | (131)
Losses charged off | (70) | (50) | (50)
Recoveries | 2 | 2 | 113
Balance, end of period | 1,091 | 1,236 | 985
Loans: |  |  |
Ending balance | 93,243 | 98,894 | 93,961
Consumer [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 52 | 65 | 65
Provision (credit) charged to expense | 8 | 1 | 37
Losses charged off | (9) | (9) | (70)
Recoveries | 4 | 2 | 20
Balance, end of period | 55 | 59 | 52
Loans: |  |  |
Ending balance | $ 5,864 | $ 7,186 | $ 5,855

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