Additional Financial Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2024 USD ($) $ / shares	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) $ / shares	Jun. 30, 2023 USD ($)	May 13, 2024 $ / shares
Dividends Payable [Line Items]
Interest payments	$ 35	$ 29	$ 125	$ 104
Income and withholding taxes paid	33	49	105	166
Noncash acquisition activities			18
Net loss (gain) on divestitures	$ 1	$ 0	$ 32	41
Debt instrument, covenant, total indebtedness to EBITDA ratio	3.50		3.50
Dividends paid	$ 89		$ 267	$ 251
Dividends paid (in dollars per share) \| $ / shares	$ 0.17		$ 0.51
Common Stock
Dividends Payable [Line Items]
Cash dividends declared (in dollars per share) \| $ / shares					$ 0.17

Aggregate dividends paid during the period for each share of common stock outstanding.

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