Income Tax - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Net discrete tax (benefits) expense related to tax settlements	$ (37)	$ 2
Uncertain tax positions from expirations of statute of limitations	$ 1	$ 1
Earliest Tax Year [Member] | United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2018
Latest Tax Year [Member] | United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2020
State Tax Authorities [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2005
State Tax Authorities [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2020
Non-U.S. Jurisdictions [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2005
Non-U.S. Jurisdictions [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2020