Intangible Assets - Components of Intangible Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 30, 2016
Finite And Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 7,811	$ 7,648
Accumulated Amortization	1,986	1,435
Unamortized intangible assets	69	68
Acquired in-process research and development
Finite And Indefinite Lived Intangible Assets [Line Items]
Unamortized intangible assets	67	66
Trademarks
Finite And Indefinite Lived Intangible Assets [Line Items]
Unamortized intangible assets	2	2
Customer relationships
Finite And Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,393	3,360
Accumulated Amortization	564	339
Developed technology
Finite And Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,508	3,409
Accumulated Amortization	1,029	754
Product rights
Finite And Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	131	125
Accumulated Amortization	54	43
Trademarks
Finite And Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	408	405
Accumulated Amortization	65	45
Patents and other
Finite And Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	370	349
Accumulated Amortization	$ 274	$ 254