Pension and Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Credit) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Pension Plan [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 11	$ 13
Expected return on plan assets	(18)	(21)
Service cost
Amortization of net actuarial loss	7	6
Net periodic benefit cost (credit)	0	(2)
Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	1	2
Expected return on plan assets	(1)	(1)
Service cost	2	1
Amortization of net actuarial loss	2	2
Net periodic benefit cost (credit)	4	4
Other Postretirement Benefits Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	1	1
Expected return on plan assets
Service cost
Amortization of net actuarial loss
Net periodic benefit cost (credit)	$ 1	$ 1