Pension and Postretirement Expense Level 4 (Details) - Estimated Future Plan Benefit Payments - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 23
Pension Plan [Member]
Defined Contribution Plan, Cost	16	$ 14	$ 20
UNITED STATES | Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	19
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	18
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	18
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	17
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	16
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	75
UNITED STATES | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	1
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	1
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	1
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	1
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	1
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	2
Foreign Plan [Member] | Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	12
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	13
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	12
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	14
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	15
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	97
Foreign Plan [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	1
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	0
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	0
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	0
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	0
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 2