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Fair Value Measurements - Fair Value Measured on Nonrecurring Basis (Details) - Nonrecurring - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | $ 596 | $ 781
Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 596 | 781
Real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Changes measurement |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total gains (losses) | (271) | (158)
Changes measurement | Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total gains (losses) | (271) | (158)
Changes measurement | Real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total gains (losses) | 0 | 0
Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Level 1 | Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Level 1 | Real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Level 2 | Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Level 2 | Real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 0 | 0
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 596 | 781
Level 3 | Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | 596 | 781
Level 3 | Real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value disclosure | $ 0 | $ 0

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- Definition Fair value adjustments to collateral dependent loans and real estate held for sale are recorded to reflect write-downs of principal balances based on the current appraised or estimated value of the collateral. + References No definition available. + Details
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