Revenue Recognition - Summary of Disaggregation of Revenue (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Total Revenues	$ 1,256	$ 1,203
Intersegment eliminations
Disaggregation of Revenue [Line Items]
Total Revenues	(1)	(3)
Operating Segments | U.S.
Disaggregation of Revenue [Line Items]
Total Revenues	534	504
Operating Segments | International
Disaggregation of Revenue [Line Items]
Total Revenues	723	702
Recorded Music
Disaggregation of Revenue [Line Items]
Total Revenues	1,084	1,041
Recorded Music | Operating Segments | U.S.
Disaggregation of Revenue [Line Items]
Total Revenues	453	431
Recorded Music | Operating Segments | International
Disaggregation of Revenue [Line Items]
Total Revenues	631	610
Recorded Music | Digital
Disaggregation of Revenue [Line Items]
Total Revenues	633	563
Recorded Music | Physical
Disaggregation of Revenue [Line Items]
Total Revenues	184	231
Recorded Music | Total Digital and Physical
Disaggregation of Revenue [Line Items]
Total Revenues	817	794
Recorded Music | Artist services and expanded-rights
Disaggregation of Revenue [Line Items]
Total Revenues	188	166
Recorded Music | Licensing
Disaggregation of Revenue [Line Items]
Total Revenues	79	81
Music Publishing
Disaggregation of Revenue [Line Items]
Total Revenues	173	165
Music Publishing | Operating Segments | U.S.
Disaggregation of Revenue [Line Items]
Total Revenues	81	73
Music Publishing | Operating Segments | International
Disaggregation of Revenue [Line Items]
Total Revenues	92	92
Music Publishing | Digital
Disaggregation of Revenue [Line Items]
Total Revenues	73	65
Music Publishing | Performance
Disaggregation of Revenue [Line Items]
Total Revenues	46	53
Music Publishing | Mechanical
Disaggregation of Revenue [Line Items]
Total Revenues	15	15
Music Publishing | Synchronization
Disaggregation of Revenue [Line Items]
Total Revenues	36	29
Music Publishing | Other
Disaggregation of Revenue [Line Items]
Total Revenues	$ 3	$ 3