Derivative Financial Instruments - Summary of Amounts Recorded in Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Derivatives, Fair Value [Line Items]
Foreign exchange derivative contracts in asset	$ 5
Foreign exchange derivative contracts in liability	3
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Foreign exchange derivative contracts in liability	13	$ 22
Other current assets
Derivatives, Fair Value [Line Items]
Other assets	2	0
Other current liabilities
Derivatives, Fair Value [Line Items]
Other liabilities	0	0
Other noncurrent assets
Derivatives, Fair Value [Line Items]
Other assets	0	0
Other noncurrent liabilities
Derivatives, Fair Value [Line Items]
Other liabilities	$ (13)	$ (22)

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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