Derivatives and Hedging Activities - Interest Rate Contracts (Details) - Interest Rate Swaps - Cash flow hedges - Designated as Hedging Instrument - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
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Jun. 30, 2026 |
Sep. 30, 2025 |
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| Derivative Instruments and Hedging Activities Disclosures [Line Items] | ||
| Notional amount | $ 300,000 | $ 225,000 |
| Weighted-average maturity period (years) | 1 year 7 months 6 days | 2 years 8 months 12 days |
| Weighted-average received rate | 3.66% | 4.13% |
| Weighted-average pay rate | 3.76% | 3.80% |
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- Definition Average fixed interest rate related to the group of interest rate derivatives. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Average period remaining until maturity of derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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/2003/role/exampleRef
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Variable interest rate in effect as of the balance sheet date related to the interest rate derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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