Pension Plans, Postretirement and Other Employee Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
US | Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1	$ 2	$ 1
Interest cost	13	3	40	8
Expected return on plan assets	(17)	(4)	(51)	(11)
Net amortization:
Actuarial loss	1	1	3	3
Prior service cost (credit)	0	0	0	0
Net pension and postretirement costs (credits)	(2)	1	(6)	1
US | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	3	2	10	5
Expected return on plan assets	0	0	0	0
Net amortization:
Actuarial loss	1	2	3	6
Prior service cost (credit)	(2)	0	(6)	(1)
Net pension and postretirement costs (credits)	2	4	7	10
Non-U.S. | Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	3	18	8
Interest cost	6	3	18	9
Expected return on plan assets	(5)	(5)	(14)	(15)
Net amortization:
Actuarial loss	1	2	4	6
Prior service cost (credit)	1	0	1	0
Net pension and postretirement costs (credits)	$ 9	$ 3	$ 27	$ 8