Fair Value Measurements - Summary of Gains (Losses) on Foreign Currency Derivatives (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member] | ||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||
| Foreign currency derivative (losses) gains | $ (1) | $ 20 | $ (3) | $ 17 |
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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 Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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