Non-pension Post-retirement Benefits (Assumptions Used) (Details) - Other Post-retirement Benefits Plan	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate used to determine accumulated postretirement benefit obligation	3.60%	4.05%	4.56%
Discount rate used to determine net postretirement benefit cost	4.05%	4.56%	4.10%
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate used to determine accumulated postretirement benefit obligation	3.26%	3.48%	3.69%
Discount rate used to determine net postretirement benefit cost	3.48%	3.69%	3.61%