Additional Financial Information - Narrative (Detail) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2023 USD ($) $ / shares	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares	Jun. 30, 2022 USD ($)	May 10, 2023 $ / shares
Dividends Payable [Line Items]
Interest payments	$ 29	$ 21	$ 104	$ 78
Income and withholding taxes paid	49	38	166	104
Net gain on divestiture	$ 0	$ 0	$ 41	0
Debt instrument, covenant, total indebtedness to EBITDA ratio	3.50		3.50
Dividends paid	$ 84		$ 251	235
Dividends paid (in dollars per share) \| $ / shares	$ 0.16		$ 0.48
Noncash investing activities related to acquisition of music publishing rights and music catalogs				$ 125
Common Stock
Dividends Payable [Line Items]
Cash dividends declared (in dollars per share) \| $ / shares					$ 0.16

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

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