Fair Value Measurements - Narrative (Details)	Mar. 31, 2022 CNY (¥) instrument	Mar. 31, 2022 USD ($) instrument	Sep. 30, 2021 USD ($)
Interest rate cap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of instruments held	2	2
Notional amount of derivative asset | $		$ 200,000,000
Foreign currency exchange derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional amount of derivative asset	¥ 150,000,000	$ 23,000,000
Net Investment Hedging | Cross-currency interest rate swaps | Japan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of instruments held	0	0
Net Investment Hedging | Cross-currency interest rate swaps | China
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of instruments held	1	1
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of long-term debt | $		$ 2,900,000,000	$ 3,800,000,000