Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Sep. 30, 2019
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total gross intangible asset subject to amortization	$ 3,405	$ 3,347
Accumulated amortization	(1,693)	(1,624)
Total net intangible assets subject to amortization	1,712	1,723
Intangible assets not subject to amortization	152	151
Total net intangible assets	1,864	1,874
Trademarks and tradenames
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization	$ 152	151
Recorded music catalog
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Weighted-Average Useful Life	10 years
Total gross intangible asset subject to amortization	$ 873	855
Music publishing copyrights
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Weighted-Average Useful Life	26 years
Total gross intangible asset subject to amortization	$ 1,563	1,539
Artist and songwriter contracts
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Weighted-Average Useful Life	13 years
Total gross intangible asset subject to amortization	$ 854	841
Trademarks
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Weighted-Average Useful Life	18 years
Total gross intangible asset subject to amortization	$ 54	53
Other intangible assets
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Weighted-Average Useful Life	7 years
Total gross intangible asset subject to amortization	$ 61	$ 59