Goodwill and intangible assets (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization charges associated with finite-lived intangible assets	$ 1,300	$ 1,500	$ 1,400
Total estimated amortization of finite- lived intangible assets for 2018	1,200
Total estimated amortization of finite- lived intangible assets for 2019	1,100
Total estimated amortization of finite- lived intangible assets for 2020	1,100
Total estimated amortization of finite-lived intangible assets for 2021	900
Total estimated amortization of finite-lived intangible assets for 2022	900
Other operating income (expense) [Member] | IPR&D [Member] | AMG 899 [Member]
Finite-Lived Intangible Assets [Line Items]
IPR&D impairment charge	$ 400