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Loans and Allowance for Credit Losses - Performance of Loans Modified (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
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30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | $ 0 | $ 0
30-59 Days Past Due | Real Estate Loan |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
30-59 Days Past Due | Consumer Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 1,228 | 96
60-89 Days Past Due | Real Estate Loan |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 505 | 0
60-89 Days Past Due | Consumer Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 96
90 Days or More Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 116
90 Days or More Past Due | Real Estate Loan |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
90 Days or More Past Due | Consumer Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 116
Total Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 1,228 | 212
Total Past Due | Real Estate Loan |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 505 | 0
Total Past Due | Consumer Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 212
Commercial Real Estate | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
Commercial Real Estate | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 505 | 0
Commercial Real Estate | 90 Days or More Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
Commercial Real Estate | Total Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 505 | 0
Commercial and Industrial Loans | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
Commercial and Industrial Loans | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 723 | 0
Commercial and Industrial Loans | 90 Days or More Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | 0 | 0
Commercial and Industrial Loans | Total Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing Receivable Modifications Performance Recorded Investment | $ 723 | $ 0

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