Income Taxes - Schedule of Reconciliation of Unrecognized Tax Benefits Including Interest and Penalties (Details) - USD ($) $ in Millions |
12 Months Ended | ||
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Sep. 30, 2024 |
Sep. 30, 2023 |
Sep. 30, 2022 |
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| Unrecognized Tax Benefits [Roll Forward] | |||
| Beginning Balance | $ 13 | $ 8 | $ 12 |
| Additions for current year tax positions | 2 | 3 | 0 |
| Additions for prior year tax positions | 0 | 9 | 1 |
| Subtractions for prior year tax positions | (3) | (7) | (5) |
| Settlements | (2) | 0 | 0 |
| Ending Balance | $ 10 | $ 13 | $ 8 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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