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Loans and Allowance for Credit Losses - Association's Loan Portfolio Aging Analysis (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Jun. 30, 2025 | Sep. 30, 2024
--- | --- | --- | ---
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | $ 3,332 | $ 3,154 |
Current | 622,106 | 636,732 |
Total loans | 625,438 | 639,886 | $ 654,189
Total Loans > 90 Days & Accruing |  | 29 |
Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 1,624 | 1,298 |
Current | 194,398 | 200,252 |
Total loans | 196,022 | 201,550 | 205,103
Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 142 | 556 |
Current | 93,101 | 93,405 |
Total loans | 93,243 | 93,961 | 98,894
Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 70 | 73 |
Current | 5,794 | 5,782 |
Total loans | 5,864 | 5,855 | 7,186
One- to four-family [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 1,369 | 1,202 |
Current | 180,248 | 177,777 |
Total loans | 181,617 | 178,979 | 176,334
Total Loans > 90 Days & Accruing |  | 29 |
Multi-family [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 113 | 25 |
Current | 118,205 | 126,102 |
Total loans | 118,318 | 126,127 | 125,906
Home equity lines of credit [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 14 |  |
Current | 10,345 | 10,487 |
Total loans | 10,359 | 10,487 | 9,927
Construction [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Current | 20,015 | 22,927 |
Total loans | 20,015 | 22,927 | $ 30,839
Financing Receivables, 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 1,374 | 2,252 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 583 | 1,049 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 20 | 256 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 8 | 56 |
Financing Receivables, 30 to 59 Days Past Due [Member] | One- to four-family [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 636 | 866 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Multi-family [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 113 | 25 |
Financing Receivables, 30 to 59 Days Past Due [Member] | Home equity lines of credit [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 14 |  |
Financing Receivables, 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 956 | 856 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 415 | 249 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due |  | 300 |
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 62 |  |
Financing Receivables, 60 to 89 Days Past Due [Member] | One- to four-family [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 479 | 307 |
Financing Receivables, Greater Than 90 Days [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 1,002 | 46 |
Financing Receivables, Greater Than 90 Days [Member] | Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 626 |  |
Financing Receivables, Greater Than 90 Days [Member] | Commercial [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 122 |  |
Financing Receivables, Greater Than 90 Days [Member] | Consumer [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | 0 | 17 |
Financing Receivables, Greater Than 90 Days [Member] | One- to four-family [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Total Past Due | $ 254 | $ 29 |

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