Long-Term Debt (Details) - USD ($) $ in Millions |
6 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Sep. 30, 2024 |
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| Debt Instrument | |||
| Long-term and short-term debt, combined amount | $ 960.0 | $ 840.0 | |
| Unamortized Debt Issuance Expense | (6.3) | (6.9) | |
| Long-term debt | 953.7 | 833.1 | |
| 7.00% Senior Notes Maturing in March 2030 | |||
| Debt Instrument | |||
| Long-Term Debt, Gross | 840.0 | 840.0 | |
| Revolving Credit Facility | |||
| Debt Instrument | |||
| Maximum borrowing capacity on line of credit | 250.0 | ||
| Repayments of lines of credit | 110.0 | $ 25.0 | |
| Long-Term Debt, Gross | 120.0 | 0.0 | |
| Letters of credit outstanding, amount | 0.0 | 0.0 | |
| Proceeds from borrowing under line of credit | 230.0 | 0.0 | |
| Line of Credit Facility [Line Items] | |||
| Remaining borrowing capacity on line of credit | 130.0 | 250.0 | |
| Letters of credit outstanding, amount | 0.0 | $ 0.0 | |
| Proceeds from borrowing under line of credit | 230.0 | $ 0.0 | |
| Letter of Credit | |||
| Debt Instrument | |||
| Maximum borrowing capacity on line of credit | $ 20.0 | ||
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Represents the aggregate of total long-term debt, including current maturities and short-term debt. No definition available.
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. No definition available.
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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/disclosureRef
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. No definition available.
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