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Loans Receivable and Allowance for Loan Losses: Significant Concentrations of Credit Risk (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024
Receivables [Abstract] |  |
Loans secured by real estate | $ 1,446,469 |
Undisbursed portion of construction loans in process (see Note 4) | $ 88,289 | $ 69,878
Loans secured by real estate, percentage of total portfolio (as a percent) | 91.81% |
Concentration of credit risk, real estate loans by industry, benchmark percentage (as a percent) | 20.00% |
Ratio of loans to appraisal or purchase price (as a percent) | 85.00% |

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- Definition Concentration of Credit Risk, Real Estate Loans by Industry, Benchmark Percentage + References No definition available. + Details
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- Definition Loans Receivable, Ratio of Loans to Appraisal or Purchase Price + References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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