Postemployment benefit plans (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
Non-U.S. pensions
Defined Benefit Plan Disclosure
Curtailments, settlements and termination benefits	$ 20

This cost (income) is included in other income/expense and includes the following: (1) curtailments that significantly reduce the expected years of future service of present employees or eliminate for a significant number of employees the accrual of defined benefits for some or all of their future services, (2) settlements that irrevocably relieve the employer (or the plan) of primary responsibility for a benefit obligation and eliminate significant risks related to the obligation and the assets used to effect the settlement and (3) termination benefits that are offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. A situation involving termination benefits may also involve a curtailment.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration