Pension Plans, Postretirement and Other Employee Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
U.S. | Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost — benefits earned during the period	$ 1	$ 0
Interest cost	13	3
Expected return on plan assets	(17)	(4)
Net amortization:
Actuarial loss	1	1
Prior service cost (credit)	0	0
Net pension and postretirement costs (credits)	(2)	0
U.S. | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost — benefits earned during the period	0	0
Interest cost	3	2
Expected return on plan assets	0	0
Net amortization:
Actuarial loss	1	1
Prior service cost (credit)	(2)	0
Net pension and postretirement costs (credits)	2	3
Non-U.S. | Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost — benefits earned during the period	6	3
Interest cost	7	3
Expected return on plan assets	(5)	(5)
Net amortization:
Actuarial loss	1	2
Prior service cost (credit)	0	0
Net pension and postretirement costs (credits)	$ 9	$ 3