Postretirement benefits Schedule of assumptions used to determine benefit obligation (Details)	Dec. 31, 2020	Dec. 31, 2019
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Benefit Obligation, Discount Rate	1.36%	2.70%
Non - U.S. | Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Benefit Obligation, Discount Rate	1.80%	2.39%
Benefit Obligation, Rate of Compensation Increase	3.24%	3.26%
UNITED STATES | Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Benefit Obligation, Discount Rate	2.32%	3.20%
Interest crediting rate	4.10%	4.10%