Pension, Savings and Other Postretirement Benefit Plans - Defined Benefit Pension Cost (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
U.S.
Defined Benefit Plan, Net Periodic Benefit Cost
Service cost — benefits earned during the period	$ 1	$ 1	$ 2	$ 2
Interest cost on projected benefit obligation	40	60	82	121
Expected return on plan assets	(63)	(75)	(127)	(150)
Amortization of net losses	27	26	54	54
Net periodic pension cost	5	12	11	27
Non-U.S.
Defined Benefit Plan, Net Periodic Benefit Cost
Service cost — benefits earned during the period	8	13	15	22
Interest cost on projected benefit obligation	21	28	41	57
Expected return on plan assets	(24)	(27)	(46)	(53)
Amortization of net losses	7	10	14	19
Net periodic pension cost	12	24	24	45
Net curtailments/settlements/termination benefits	13	1	13	1
Total defined benefit pension cost	$ 25	$ 25	$ 37	$ 46