Pension and Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Credit) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
United States Pension Plan of US Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 13	$ 17	$ 26	$ 34
Expected return on plan assets	(23)	(28)	(46)	(55)
Service cost
Amortization of net actuarial loss	5	5	10	10
Net periodic benefit cost (credit)	(5)	(6)	(10)	(11)
Foreign Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	2	2	4	4
Expected return on plan assets			(1)	(1)
Service cost	1	1	2	3
Other	1		1
Amortization of net actuarial loss	1	2	3	3
Net periodic benefit cost (credit)	5	5	9	9
Foreign Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	1	1	2	2
Expected return on plan assets
Service cost
Amortization of net actuarial loss
Net periodic benefit cost (credit)	$ 1	$ 1	$ 2	$ 2