Financial Instruments and Fair Value Measurements - Fair Values of Financial Instruments (Detail) - Recurring Fair Value Measurements - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Assets
Institutional money market investments	$ 224	$ 147
Interest rate swaps	23	19
Forward exchange contracts	3	13
Total Assets	249	179
Liabilities
Forward exchange contracts	13	21
Commodity forward contracts	0	10
Interest rate swaps	18
Contingent consideration liabilities	54	77
Total Liabilities	86	108
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Institutional money market investments	224	147
Interest rate swaps	0	0
Forward exchange contracts	0	0
Total Assets	224	147
Liabilities
Forward exchange contracts	0	0
Commodity forward contracts	0	0
Interest rate swaps	0
Contingent consideration liabilities	0	0
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2)
Assets
Institutional money market investments	0	0
Interest rate swaps	23	19
Forward exchange contracts	3	13
Total Assets	25	32
Liabilities
Forward exchange contracts	13	21
Commodity forward contracts	0	10
Interest rate swaps	18
Contingent consideration liabilities	0	0
Total Liabilities	31	30
Significant Unobservable Inputs (Level 3)
Assets
Institutional money market investments	0	0
Interest rate swaps	0	0
Forward exchange contracts	0	0
Total Assets	0	0
Liabilities
Forward exchange contracts	0	0
Commodity forward contracts	0	0
Interest rate swaps	0
Contingent consideration liabilities	54	77
Total Liabilities	$ 54	$ 77