Postretirement Benefit Plans (Components of Pension Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other changes in plan assets and benefit obligations recognized in other comprehensive income
Net loss	$ (20)	$ 23	$ (110)
Prior service cost	1	1	17
Settlement	0	0	(1)
Total recognized in comprehensive income	8	6	(2)
Domestic defined benefit pension plans
Net periodic benefit cost:
Service cost	3	3	2
Interest cost	4	4	3
Expected return on plan assets	(5)	(5)	(4)
Amortization of net actuarial loss	2	2	2
Net periodic benefit cost	4	4	3
Other changes in plan assets and benefit obligations recognized in other comprehensive income
Net loss	1	(2)	(14)
Prior service cost	0	0	(1)
Amortization of net actuarial loss	(2)	(2)	(2)
Change recognized in other comprehensive income	(3)	0	13
International defined benefit pension plans
Net periodic benefit cost:
Service cost	10	12	12
Interest cost	21	22	27
Expected return on plan assets	(30)	(32)	(32)
Amortization of net actuarial loss	8	13	7
Settlement	0	0	1
Net periodic benefit cost	9	15	15
Other changes in plan assets and benefit obligations recognized in other comprehensive income
Net loss	(18)	29	(84)
Prior service cost	1	0	0
Amortization of net actuarial loss	(8)	(13)	(7)
Settlement	0	0	(1)
Foreign Exchange	(20)	(21)	(20)
Change recognized in other comprehensive income	(11)	(63)	56
Defined benefit pension plans
Net periodic benefit cost:
Net periodic benefit cost	13	19	18
Other changes in plan assets and benefit obligations recognized in other comprehensive income
Change recognized in other comprehensive income	(14)	(63)	69
Total recognized in comprehensive income	$ (1)	$ (44)	$ 87