Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Sep. 30, 2025 |
|---|---|---|
| Debt Instrument [Line Items] | ||
| Total | $ 1,250.0 | $ 1,390.0 |
| Unamortized debt issuance costs | 5.6 | 6.7 |
| Long-term debt | 1,244.4 | 1,383.3 |
| Revolving credit facility | ||
| Debt Instrument [Line Items] | ||
| Total | 0.0 | 140.0 |
| Senior Notes, Due 2028 | Senior notes | ||
| Debt Instrument [Line Items] | ||
| Total | 750.0 | 750.0 |
| Unamortized debt issuance costs | 3.2 | 3.9 |
| Senior Notes, Due 2029 | Senior notes | ||
| Debt Instrument [Line Items] | ||
| Total | 500.0 | 500.0 |
| Unamortized debt issuance costs | $ 2.4 | $ 2.8 |
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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 Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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