Pension, Other Postretirement Benefits and Savings Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plans, contribution expenses		$ 111	$ 111	$ 122
Minimum
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to funded non-U.S. pension plans in next year		25
Maximum
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to funded non-U.S. pension plans in next year		50
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement		0	0
Service cost		3	4	3
Increase (decrease) for plan amendment		(14)	3
Settlement charge		0	0	2
Benefits (credit) cost		11	(7)	(23)
Estimated net actuarial loss that will be amortized from AOCL into benefits cost in the next year		4
Estimated prior service credit that will be amortized from AOCL into benefits cost in the next year		9
Prescription drug subsidy		1
Postretirement benefits funded status		231	282
Pension benefit obligation		234	286	294
AOCL adjustment		(7)	20
United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Settlement charge		13
Settlement		103
Service cost		13
United Kingdom | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement charge	$ 14
Settlement of benefit obligation	$ 41
United States
Defined Benefit Plan Disclosure [Line Items]
Settlement charge		8	32
Accumulated benefit obligation		$ 4,725	5,320
United States | Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation		94.00%
United States | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation		6.00%
United States | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement		$ 22	55
Service cost		4	4	5
Increase (decrease) for plan amendment		0	0
Settlement charge		8	29	0
Benefits (credit) cost		62	63	$ 23
Estimated net actuarial loss that will be amortized from AOCL into benefits cost in the next year		114
Estimated prior service credit that will be amortized from AOCL into benefits cost in the next year		0
Postretirement benefits funded status		$ 289	$ 353
Weighted average discount rate		3.09%	3.18%	3.23%
Assumed weighted average long term rate of return		4.58%	5.08%	5.33%
Pension benefit obligation		$ 4,734	$ 5,331	$ 5,285
AOCL adjustment		2,490	2,599
United States | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefits (credit) cost		4	(17)	$ (31)
Postretirement benefits funded status		$ 112	$ 132
Weighted average discount rate		2.99%	3.02%	2.98%
United States | Other (Income) Expense
Defined Benefit Plan Disclosure [Line Items]
Settlement charge			$ 19
United States | Rationalization Charges
Defined Benefit Plan Disclosure [Line Items]
Settlement charge			13
BRAZIL | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) for plan amendment		$ 16
BRAZIL | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) for plan amendment		(14)
Non-U.S.
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 2,688	3,017
Non-U.S. | Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation		95.00%
Non-U.S. | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation		5.00%
Non-U.S. | Unfunded Plan
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 218	227
Pension benefit obligation		244	251
AOCL adjustment		59	59
Non-U.S. | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement		112	11
Service cost		28	31	$ 29
Increase (decrease) for plan amendment		29	3
Settlement charge		13	3	16
Benefits (credit) cost		69	57	$ 64
Estimated net actuarial loss that will be amortized from AOCL into benefits cost in the next year		29
Estimated prior service credit that will be amortized from AOCL into benefits cost in the next year		2
Postretirement benefits funded status		$ 310	$ 303
Weighted average discount rate		2.56%	2.70%	3.37%
Assumed weighted average long term rate of return		3.02%	3.12%	3.81%
Pension benefit obligation		$ 2,774	$ 3,109	$ 2,863
AOCL adjustment		642	673
Non-U.S. | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefits (credit) cost		7	10	$ 8
Postretirement benefits funded status		$ 119	$ 150
Weighted average discount rate		6.13%	5.98%	6.31%