Commitment and Contingencies (Details) - USD ($) $ in Thousands |
Mar. 31, 2026 |
Sep. 30, 2025 |
|---|---|---|
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Loans receivable, net | $ 19,966,983 | $ 20,088,618 |
| Reserve for unfunded commitments | 22,500 | |
| Investment, proportional amortization method, elected, amount | $ 149,253 | $ 157,249 |
| Investment, Proportional Amortization Method, Elected, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets |
| Investment program, proportional amortization method, elected, commitment | $ 63,128 | $ 73,123 |
| FHLB advances | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Loans receivable, net | 30,500 | 62,606 |
| Unfunded commitments | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Loans receivable, net | $ 3,066,873 | $ 2,841,596 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Indicates line item in statement of financial position that includes investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of commitment and contingent commitment, including amount of delayed equity contribution, for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, commitment and contingent commitment related to investment under tax credit program not meeting condition for accounting under proportional amortization method. Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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