Goodwill and Intangible Assets - Changes in Goodwill for Each Reportable Segment (Detail) $ in Millions	3 Months Ended
	Dec. 31, 2017 USD ($)
Goodwill [Line Items]
Beginning balance	$ 1,685
Other adjustments	3	[1]
Ending balance	1,688
Recorded Music
Goodwill [Line Items]
Beginning balance	1,221
Other adjustments	3	[1]
Ending balance	1,224
Music Publishing
Goodwill [Line Items]
Beginning balance	464
Ending balance	$ 464

[1] Other adjustments during the three months ended December 31, 2017 represent foreign currency movements.