Financial Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Four Quarter Rolling Average of Notional Amount of Foreign Exchange Contracts Hedging Foreign Currency Transactions	$ 18,000		$ 18,000		$ 15,600
Description of Net Investment Hedge Activity			we have issued approximately €2.95 billion of Euro-denominated debt, which qualifies as a net investment hedge against our investments in European businesses. As of September 30, 2016, the net investment hedge is deemed to be effective.
Derivatives designated as hedging instruments, Asset Derivatives	30		$ 30		4
Derivatives not designated as hedging instruments, Asset Derivatives	71		71		97
Derivatives designated as hedging instruments, Liability Derivatives	130		130		428
Derivatives not designated as hedging instruments, Liability Derivatives	51		51		$ 105
(Loss) gain recorded in Accumulated other comprehensive loss	(7)	$ (152)	188	$ (274)
Loss reclassified from Accumulated other comprehensive loss into Product Sales (effective portion)	32	64	139	164
Foreign Currency Cash Flow Hedge Loss to be Reclassified During Next 12 Months	53		$ 53
Maximum Length of Time, Foreign Currency Cash Flow Hedge			6 years 1 month 23 days
Gain recognized in Other income, net	$ 19	$ 35	$ 49	65
(Payments) receipts from settlements of derivative contracts			$ 29	$ (147)