Pension and Other Postretirement Benefit Plans - Net Periodic Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		75 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	$ 3	$ 2	$ 5	$ 4	$ (103)
Operating profit | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	2	2	4	4
Interest and sundry (income) expense | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	1	0	1	0
United States Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	2	1	4	3
United States Pension Benefits | Operating profit
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	0	0	1	1
United States Pension Benefits | Interest and sundry (income) expense
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	2	1	3	2
Foreign Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	2	1	3	3
Foreign Pension Benefits | Operating profit
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	2	2	3	3
Foreign Pension Benefits | Interest and sundry (income) expense
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost	$ 0	$ (1)	$ 0	$ 0