Postretirement Benefit Plans - Benefit Obligations and Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Funded status (FVPA – BO) at end of year	$ (48)	$ (133)
U.S. defined benefit plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year:	1,033	1,076
Service cost	22	22	$ 21
Interest cost	42	43	45
Participant contributions	0	0
Benefits paid	(9)	(8)
Medicare subsidy	0	0
Actuarial loss (gain)	27	(6)
Settlements	(85)	(94)
Plan amendments	0	0
Effects of exchange rate changes	0	0
Benefit obligation at end of year (BO)	1,030	1,033	1,076
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year:	1,019	1,082
Actual return on plan assets	79	(24)
Employer contributions (funding of qualified plans)	15	52
Employer contributions (payments for non-qualified plans)	15	11
Participant contributions	0	0
Benefits paid	(9)	(8)
Settlements	(85)	(94)
Effects of exchange rate changes	0	0
Other	0	0
Fair value of plan assets at end of year (FVPA)	1,034	1,019	1,082
Funded status (FVPA – BO) at end of year	4	(14)
U.S. retiree health care plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year:	463	513
Service cost	5	5	4
Interest cost	20	20	22
Participant contributions	10	19
Benefits paid	(38)	(46)
Medicare subsidy	1	3
Actuarial loss (gain)	(27)	(21)
Settlements	0	0
Plan amendments	0	(30)
Effects of exchange rate changes	0	0
Benefit obligation at end of year (BO)	434	463	513
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year:	441	497
Actual return on plan assets	20	0
Employer contributions (funding of qualified plans)	1	1
Employer contributions (payments for non-qualified plans)	0	0
Participant contributions	10	19
Benefits paid	(38)	(46)
Settlements	0	0
Effects of exchange rate changes	0	0
Other	0	(30)
Fair value of plan assets at end of year (FVPA)	434	441	497
Funded status (FVPA – BO) at end of year	0	(22)
Non-U.S. defined benefit plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year:	2,231	2,316
Service cost	34	35	39
Interest cost	52	53	68
Participant contributions	6	6
Benefits paid	(77)	(73)
Medicare subsidy	0	0
Actuarial loss (gain)	259	14
Settlements	(8)	(18)
Plan amendments	0	0
Effects of exchange rate changes	(136)	(102)
Benefit obligation at end of year (BO)	2,361	2,231	2,316
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year:	2,134	2,213
Actual return on plan assets	227	25
Employer contributions (funding of qualified plans)	160	72
Employer contributions (payments for non-qualified plans)	0	0
Participant contributions	6	6
Benefits paid	(77)	(73)
Settlements	(8)	(18)
Effects of exchange rate changes	(133)	(91)
Other	0	0
Fair value of plan assets at end of year (FVPA)	2,309	2,134	$ 2,213
Funded status (FVPA – BO) at end of year	$ (52)	$ (97)