Additional Financial Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2024 USD ($) $ / shares	Mar. 31, 2023 USD ($)	Mar. 31, 2024 USD ($) $ / shares	Mar. 31, 2023 USD ($)	Feb. 12, 2024 $ / shares
Dividends Payable [Line Items]
Interest payments	$ 57	$ 50	$ 90	$ 75
Income and withholding taxes paid	33	72	72	117
Noncash acquisition activities			18
Net loss (gain) on divestitures	$ 14	$ 0	$ 31	41
Debt instrument, covenant, total indebtedness to EBITDA ratio	3.50		3.50
Dividends paid	$ 89		$ 178	$ 167
Dividends paid (in dollars per share) \| $ / shares	$ 0.17		$ 0.34
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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