Comprehensive Income (Loss) - Schedule of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions		12 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance		$ 239	$ 390	$ 743
Ending balance		210	239	390
Foreign Currency Translation Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance		(157)	(98)	(57)
Other comprehensive loss	[1]	(44)	(59)	(41)
Ending balance		(201)	(157)	(98)
Minimum Pension Liability Adjustment
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance		(10)	(10)	(4)
Other comprehensive loss	[1]	(6)		(6)
Amounts reclassified from accumulated other comprehensive income		(1)
Ending balance		(17)	(10)	(10)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance		(167)	(108)	(61)
Other comprehensive loss	[1]	(50)	(59)	(47)
Amounts reclassified from accumulated other comprehensive income		(1)
Ending balance		$ (218)	$ (167)	$ (108)

[1] Foreign currency translation adjustments include intra-entity foreign currency transactions that are of a long-term investment nature of $(108) million, $(63) million and $(13) million during the fiscal year ended September 30, 2016, 2015 and 2014, respectively.