Fair value measurement (Details Textual) - USD ($)		12 Months Ended
	Oct. 14, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Oct. 31, 2015
Fair Value Measurement (Textual) [Abstract]
Length of time hedged in foreign currency contracts		3 years
Payment of contingent consideration obligation		$ 0	$ 253,000,000	$ 92,000,000
Aggregate fair value of long-term debt, including current portion		36,500,000,000	33,100,000,000
Carrying value of long-term debt, including current portion		34,596,000,000	31,429,000,000
Dezima [Member]
Fair Value Measurement (Textual) [Abstract]
Maximum additional consideration due contingent on certain milestones	$ 1,250,000,000.00				$ 1,250,000,000.00
Estimated fair values of contingent consideration obligations	$ 110,000,000
Biovex [Member]
Fair Value Measurement (Textual) [Abstract]
Payment of contingent consideration obligation			$ 125,000,000
Additional contingent consideration upon achievement of milestones		$ 325,000,000
Other government-related and corporate debt securities [Member]
Fair Value Measurement (Textual) [Abstract]
Investment maturity period		5 years