Pension and Other Postretirement Benefit Plans - Net Periodic Costs Recognized in Operating Profit and Interest and Sundry (Income) Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ (10)	$ (2)	$ (20)	$ 1
Operating profit (loss) | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	0	1	0	3
Interest and sundry (income) expense | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	(10)	(3)	(20)	(2)
United States Pension Benefits | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	0	(1)	(2)	(1)
United States Pension Benefits | Operating profit (loss) | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	0	0	1	1
United States Pension Benefits | Interest and sundry (income) expense | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	0	(1)	(3)	(2)
Foreign Pension Benefits | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	2	2	3	3
Foreign Pension Benefits | Operating profit (loss) | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	2	1	3	3
Foreign Pension Benefits | Interest and sundry (income) expense | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ 0	$ 1	$ 0	$ 0