Pension and Postretirement Expense Level 4 (Details) - Non-U.S. Pension Plan Investments Measured at Fair Value - Foreign Plan [Member] - Pension Plan [Member] - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pooled Insurance Products with Fixed Income Guarantee	$ 11	$ 9
Pension Benefits Fair Value of Plan Assets of Underfunded Plans	391	9
Fair value of plan assets at end of year subtotal	11	9
Other international equity funds	90	82
Other fixed income securities	311	258
Defined Benefit Plan, Fair Value of Plan Assets	412	349	$ 316
Fair Value, Inputs, Level 1 [Member]
Pooled Insurance Products with Fixed Income Guarantee	0	0
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member]
Pooled Insurance Products with Fixed Income Guarantee	11	9
Defined Benefit Plan, Fair Value of Plan Assets	11	9
Fair Value, Inputs, Level 3 [Member]
Pooled Insurance Products with Fixed Income Guarantee	0	0
Defined Benefit Plan, Fair Value of Plan Assets	$ 0	$ 0