Pension and Postretirement Expense Level 4 (Details) - Components of Net Pension and Non-pension postretirement Expense - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
UNITED STATES
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	$ 0
Foreign Plan [Member]
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0
Other Postretirement Benefits Plan [Member] | UNITED STATES
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Service cost	0	$ 0
Interest cost	0	0	$ 0
Amortization of prior service cost (benefit)	0	(1)	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0
Unrealized actuarial (gain) loss	(1)	0	0
Net expense (benefit)	(1)	(1)	0
Other Postretirement Benefits Plan [Member] | Foreign Plan [Member]
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Service cost	0	0
Interest cost	1	1	1
Amortization of prior service cost (benefit)	0	0	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(1)
Unrealized actuarial (gain) loss	1	(1)	(1)
Net expense (benefit)	2	0	0
Pension Plan [Member] | UNITED STATES
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Service cost	3	3	3
Interest cost	7	8	10
Expected return on assets	(13)	(14)	(15)
Amortization of prior service cost (benefit)	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0	1	0
Unrealized actuarial (gain) loss	(6)	1	0
Net expense (benefit)	(9)	(1)	(2)
Pension Plan [Member] | Foreign Plan [Member]
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Service cost	16	14	16
Interest cost	9	10	12
Expected return on assets	(11)	(10)	(13)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(1)	(1)	0
Unrealized actuarial (gain) loss	1	35	(16)
Net expense (benefit)	$ 14	$ 48	$ (1)