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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, 2024 | Sep. 30, 2023 | Jun. 30, 2024
Allowance for loan losses: |  |  |
Balance, beginning of period | $ 7,499 | $ 7,139 | $ 7,139
Provision (credit) charged to expense | 377 | 310 | 150
Losses charged off | (409) | (7) | (49)
Recoveries | 5 | 8 | 259
Balance, end of period | 7,472 | 7,450 | 7,499
Loans: |  |  |
Ending balance | 654,189 | 621,771 | 646,389
One- to Four-Family [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 1,774 | 1,898 | 1,898
Provision (credit) charged to expense | (147) | 8 | (127)
Losses charged off | 0 | 0 | 0
Recoveries | 1 | 0 | 3
Balance, end of period | 1,628 | 1,906 | 1,774
Loans: |  |  |
Ending balance | 176,334 | 170,154 | 177,263
Multi-Family [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 1,764 | 1,121 | 1,121
Provision (credit) charged to expense | 348 | (6) | 643
Losses charged off | (350) | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 1,762 | 1,115 | 1,764
Loans: |  |  |
Ending balance | 125,906 | 89,177 | 126,031
Home Equity Lines of Credit [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 148 | 121 | 121
Provision (credit) charged to expense | (1) | 13 | 27
Losses charged off | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 147 | 134 | 148
Loans: |  |  |
Ending balance | 9,927 | 8,511 | 9,859
Construction [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 337 | 765 | 765
Provision (credit) charged to expense | (59) | 400 | (428)
Losses charged off | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 278 | 1,165 | 337
Loans: |  |  |
Ending balance | 30,839 | 72,810 | 33,708
Commercial [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 2,358 | 2,369 | 2,369
Provision (credit) charged to expense | 4 | (104) | (11)
Losses charged off | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Balance, end of period | 2,362 | 2,265 | 2,358
Loans: |  |  |
Ending balance | 205,103 | 193,582 | 200,017
Commercial [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 1,053 | 794 | 794
Provision (credit) charged to expense | 231 | (12) | 17
Losses charged off | (50) | 0 | 0
Recoveries | 2 | 6 | 242
Balance, end of period | 1,236 | 788 | 1,053
Loans: |  |  |
Ending balance | 98,894 | 79,194 | 91,784
Consumer [Member] |  |  |
Allowance for loan losses: |  |  |
Balance, beginning of period | 65 | 71 | 71
Provision (credit) charged to expense | 1 | 11 | 29
Losses charged off | (9) | (7) | (49)
Recoveries | 2 | 2 | 14
Balance, end of period | 59 | 77 | 65
Loans: |  |  |
Ending balance | $ 7,186 | $ 8,343 | $ 7,727

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