Pension and Postretirement Expense Level 4 (Details) - Weighted Average Rates used to Determine Net Periodic Pension Expense - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components	$ 2
Foreign Plan [Member] | Pension Plan [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	1.90%	2.30%	2.20%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	2.40%	2.40%	3.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	2.90%	3.10%	3.80%
Foreign Plan [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	6.00%	5.50%	6.10%
UNITED STATES | Pension Plan [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	3.90%	4.10%	3.70%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	0.00%	0.00%	0.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	6.70%	6.70%	7.00%
UNITED STATES | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	3.50%	3.40%	3.40%