Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Revenue	$ 6,426	$ 6,037	$ 5,919
Adjusted OIBDA	1,432	1,235	1,149
Total assets	9,155	8,545
Capital expenditures	116	127	135
Operating Segments | Recorded Music
Segment Reporting Information [Line Items]
Revenue	5,223	4,955	4,966
Adjusted OIBDA	1,282	1,093	1,046
Total assets	4,945	4,677
Capital expenditures	28	39	52
Operating Segments | Music Publishing
Segment Reporting Information [Line Items]
Revenue	1,210	1,088	958
Adjusted OIBDA	330	296	233
Total assets	3,017	2,781
Capital expenditures	1	1	1
Corporate expenses and eliminations
Segment Reporting Information [Line Items]
Revenue	(7)	(6)	(5)
Adjusted OIBDA	(180)	(154)	(130)
Total assets	1,193	1,087
Capital expenditures	$ 87	$ 87	$ 82