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Additional Financial Information - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Aug. 05, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Dividends Payable [Line Items]
Interest payments		$ 36	$ 43	$ 128	$ 114
Income and withholding taxes paid		53	50	179	151
Noncash investing activities related to acquisition of music publishing rights and music catalogs				87	32
Net loss on divestitures		$ 0	$ 0	$ 5	0
Pre-tax realized net gain on sale of an investment					$ 29
Dividends (in dollars per share)		$ 0.19	$ 0.18	$ 0.57	$ 0.54
Dividends paid		$ 100		$ 300	$ 283
Class A Common Stock
Dividends Payable [Line Items]
Dividends (in dollars per share)		$ 0.19
Dividends paid (in dollars per share)		0.19		$ 0.57
Class A Common Stock \| Subsequent Event
Dividends Payable [Line Items]
Dividends (in dollars per share)	$ 0.20
Class B Common Stock
Dividends Payable [Line Items]
Dividends (in dollars per share)		0.19
Dividends paid (in dollars per share)		$ 0.19		$ 0.57
Class B Common Stock \| Subsequent Event
Dividends Payable [Line Items]
Dividends (in dollars per share)	$ 0.20
Recorded Music
Dividends Payable [Line Items]
Impairment expense		$ 3	$ 70	$ 14	$ 70