Derivatives and Other Financial Instruments - Schedule of Carrying Values and Fair Values of Other Financial Instruments (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Carrying Value [Member]
Derivative [Line Items]
Cash and cash equivalents	$ 1,863	$ 1,919
Restricted cash	1,337	37
Noncurrent receivables	19	17
Available-for-sale securities	83	193
Short-term borrowings	32	38
Commercial paper	0	0
Long-term debt due within one year	773	21
Contingent payment related to an acquisition	133	130
Long-term debt, less amount due within one year	9,501	8,993
Fair Value [Member]
Derivative [Line Items]
Cash and cash equivalents	1,863	1,919
Restricted cash	1,337	37
Noncurrent receivables	19	17
Available-for-sale securities	83	193
Short-term borrowings	32	38
Commercial paper	0	0
Long-term debt due within one year	783	21
Contingent payment related to an acquisition	133	130
Long-term debt, less amount due within one year	$ 10,195	$ 8,922