Investments - Summary of Investments (Details) - USD ($) $ in Millions |
Mar. 31, 2025 |
Sep. 30, 2024 |
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| Investments, Debt and Equity Securities [Abstract] | ||
| Fixed income securities | $ 6.0 | $ 0.0 |
| Equity securities (other) | 100.0 | 106.0 |
| Other | 71.0 | 63.0 |
| Total investments | 177.0 | 169.0 |
| Less: Short-term Investments | (6.0) | 0.0 |
| Long-term investments | $ 171.0 | $ 169.0 |
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investments classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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