Fair Value Measurements - Fair Value of Debt (Details) - USD ($) $ in Millions |
Jun. 30, 2025 |
Sep. 30, 2024 |
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| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Unamortized discounts and issuance costs | $ (6.9) | $ (5.6) |
| Level 2 | Fair value | Senior Notes | 2031 Notes | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, fair value | 485.2 | 478.5 |
| Level 2 | Carrying Value | Senior Notes | 2031 Notes | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, fair value | 530.9 | 530.4 |
| Unamortized discounts and issuance costs | $ (4.1) | $ (4.6) |
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- Definition Amount of unamortized debt discount (premium) and debt issuance costs. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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 The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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