Goodwill and Intangible Assets - Schedule of Changes in Goodwill for Each Reportable Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Goodwill [Roll Forward]
Beginning balance	$ 1,993	$ 1,920
Acquisitions	5	51
Other adjustments	23	22
Ending balance	2,021	1,993
Recorded Music
Goodwill [Roll Forward]
Beginning balance	1,529	1,456
Acquisitions	5	51
Other adjustments	23	22
Ending balance	1,557	1,529
Music Publishing
Goodwill [Roll Forward]
Beginning balance	464	464
Acquisitions	0	0
Other adjustments	0	0
Ending balance	$ 464	$ 464