Derivative Financial Instruments - Schedule of Derivative Instruments at Gross Value (Details) - USD ($) $ in Millions |
Sep. 30, 2021 |
Sep. 30, 2020 |
|---|---|---|
| Foreign exchange contracts | Designated as Hedging Instrument | Prepaid expenses and other current assets and other assets | ||
| Derivative [Line Items] | ||
| Assets | $ 270 | $ 257 |
| Foreign exchange contracts | Designated as Hedging Instrument | Accrued liabilities | ||
| Derivative [Line Items] | ||
| Liabilities | 13 | 39 |
| Foreign exchange contracts | Not Designated as Hedging Instrument | Prepaid expenses and other current assets | ||
| Derivative [Line Items] | ||
| Assets | 2 | 7 |
| Foreign exchange contracts | Not Designated as Hedging Instrument | Accrued liabilities | ||
| Derivative [Line Items] | ||
| Liabilities | 6 | 5 |
| Interest rate swap | Designated as Hedging Instrument | Other assets | ||
| Derivative [Line Items] | ||
| Assets | 138 | 248 |
| Cross-currency swap | Designated as Hedging Instrument | Other liabilities | ||
| Derivative [Line Items] | ||
| Liabilities | $ 90 | $ 137 |