Pension and Other Retiree Benefits (Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension | U.S.
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.80%	4.60%	4.20%
Expected long-term rate of return	7.80%	7.80%	8.00%
Pension | International
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.30%	3.70%	3.40%
Expected long-term rate of return	5.50%	6.00%	6.50%
Rate of compensation increase	3.10%	3.00%	3.00%
Post-retirement
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.40%	3.90%	3.70%