Pension plans 3 (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
U.S. Pension Plans [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Weighted-average discount rate	5.00%	4.00%
Rate of increase in future compensation levels	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Weighted-average discount rate	4.13%	4.25%	5.25%
Expected return on plan assets	8.00%	8.00%	8.25%
Rate of increase in future compensation levels	3.75%	4.25%	4.25%
Non-U.S. Pension Plans [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Weighted-average discount rate	4.25%	3.89%
Rate of increase in future compensation levels	3.91%	3.79%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Weighted-average discount rate	3.89%	4.68%	5.28%
Expected return on plan assets	6.01%	6.32%	6.34%
Rate of increase in future compensation levels	3.79%	3.81%	3.93%