Goodwill and Intangible Assets - Changes in Goodwill for Each Reportable Segment (Detail) $ in Millions	6 Months Ended
	Mar. 31, 2019 USD ($)
Goodwill [Line Items]
Beginning balance	$ 1,692
Acquisitions	109	[1]
Divestitures	(1)
Other adjustments	(13)	[2]
Ending balance	1,787
Recorded Music
Goodwill [Line Items]
Beginning balance	1,228
Acquisitions	109	[1]
Divestitures	(1)
Other adjustments	(13)	[2]
Ending balance	1,323
Music Publishing
Goodwill [Line Items]
Beginning balance	464
Ending balance	$ 464

[1] Relates to the acquisition of EMP during the six months ended March 31, 2019.

[2] Other adjustments during the six months ended March 31, 2019 represent foreign currency movements.