Investments - Schedule of Investments (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Sep. 30, 2025 |
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| Investments, Debt and Equity Securities [Abstract] | ||
| Equity securities (other) | $ 108 | $ 105 |
| Other | 82 | 77 |
| Long-term investments | $ 190 | $ 182 |
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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 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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