Goodwill and Intangible Assets - Changes in Goodwill for Each Reportable Segment (Detail) $ in Millions	6 Months Ended
	Mar. 31, 2017 USD ($)
Goodwill [Line Items]
Beginning balance	$ 1,627
Acquisitions	2
Divestitures	(2)
Other adjustments	(13)	[1]
Ending balance	1,614
Recorded Music
Goodwill [Line Items]
Beginning balance	1,163
Acquisitions	2
Divestitures	(2)
Other adjustments	(13)	[1]
Ending balance	1,150
Music Publishing
Goodwill [Line Items]
Beginning balance	464
Ending balance	$ 464

[1] Other adjustments during the six months ended March 31, 2017 primarily include foreign currency movements.