Financial Instruments and Fair Value Measurements - Fair Values of Financial Instruments (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Dec. 31, 2015	Sep. 30, 2015
Assets
Institutional money market investments	$ 392	$ 147
Interest rate swaps	13	19
Forward exchange contracts	7	13
Total Assets	411	179
Liabilities
Forward exchange contracts	4	21
Commodity forward contracts	7	10
Contingent consideration liabilities	78	77
Total Liabilities	89	108
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Institutional money market investments	392	147
Interest rate swaps	0	0
Forward exchange contracts	0	0
Total Assets	392	147
Liabilities
Forward exchange contracts	0	0
Commodity forward contracts	0	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	13	19
Forward exchange contracts	7	13
Total Assets	20	32
Liabilities
Forward exchange contracts	4	21
Commodity forward contracts	7	10
Contingent consideration liabilities	0	0
Total Liabilities	11	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
Contingent consideration liabilities	78	77
Total Liabilities	$ 78	$ 77