Financial Instruments and Fair Value Measurements - Fair Values of Financial Instruments (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Mar. 31, 2016	Sep. 30, 2015
Assets
Institutional money market investments	$ 477	$ 147
Interest rate swaps	24	19
Forward exchange contracts	22	13
Total Assets	523	179
Liabilities
Forward exchange contracts	9	21
Commodity forward contracts	5	10
Interest rate swaps	3
Contingent consideration liabilities	57	77
Total Liabilities	73	108
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Institutional money market investments	477	147
Interest rate swaps	0	0
Forward exchange contracts	0	0
Total Assets	477	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	24	19
Forward exchange contracts	22	13
Total Assets	46	32
Liabilities
Forward exchange contracts	9	21
Commodity forward contracts	5	10
Interest rate swaps	3
Contingent consideration liabilities	0	0
Total Liabilities	16	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	57	77
Total Liabilities	$ 57	$ 77