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Additional Financial Information - Additional Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended
	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($)	Feb. 08, 2022 $ / shares	Nov. 09, 2021 $ / shares
Dividends Payable [Line Items]
Interest payments	$ 13	$ 27
Income and withholding taxes paid	29	17
Dividends paid	$ 78	$ 62
Dividends paid (in dollars per share) \| $ / shares	$ 0.15
Noncash investing activities related to acquisition of music publishing rights and music catalogs	$ 125
Revolving Credit Facility \| Line of Credit
Dividends Payable [Line Items]
Debt instrument, covenant, total indebtedness to EBITDA ratio	3.50
Common Stock
Dividends Payable [Line Items]
Cash dividends declared (in dollars per share) \| $ / shares				$ 0.15
Common Stock \| Subsequent Event
Dividends Payable [Line Items]
Cash dividends declared (in dollars per share) \| $ / shares			$ 0.15