Fair Value Measurements - Schedule of the Fair Value Hierarchy for Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$ 12	$ 9
Total liabilities	16	28
Other current assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	11	8
Other noncurrent assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	1
Other noncurrent assets | Interest rate cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset		1
Other current liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	13	24
Other current liabilities | Cross-currency interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability		0
Other noncurrent liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	3	4
Quoted Prices in Active Markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Total liabilities	0	0
Quoted Prices in Active Markets (Level 1) | Other current assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0	0
Quoted Prices in Active Markets (Level 1) | Other noncurrent assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0
Quoted Prices in Active Markets (Level 1) | Other noncurrent assets | Interest rate cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset		0
Quoted Prices in Active Markets (Level 1) | Other current liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	0	0
Quoted Prices in Active Markets (Level 1) | Other current liabilities | Cross-currency interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability		0
Quoted Prices in Active Markets (Level 1) | Other noncurrent liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	12	9
Total liabilities	16	28
Significant Other Observable Inputs (Level 2) | Other current assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	11	8
Significant Other Observable Inputs (Level 2) | Other noncurrent assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	1
Significant Other Observable Inputs (Level 2) | Other noncurrent assets | Interest rate cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset		1
Significant Other Observable Inputs (Level 2) | Other current liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	13	24
Significant Other Observable Inputs (Level 2) | Other current liabilities | Cross-currency interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability		0
Significant Other Observable Inputs (Level 2) | Other noncurrent liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	3	4
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Total liabilities	0	0
Significant Unobservable Inputs (Level 3) | Other current assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0	0
Significant Unobservable Inputs (Level 3) | Other noncurrent assets | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0
Significant Unobservable Inputs (Level 3) | Other noncurrent assets | Interest rate cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset		0
Significant Unobservable Inputs (Level 3) | Other current liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	0	0
Significant Unobservable Inputs (Level 3) | Other current liabilities | Cross-currency interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability		0
Significant Unobservable Inputs (Level 3) | Other noncurrent liabilities | Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liability	$ 0	$ 0