Supplemental Equity and Comprehensive Income Information - Reclass AOCI (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net of tax	$ (52)	$ (55)	$ (137)	$ (190)
Gains (losses) associated with defined benefit pension and postretirement plans amortization
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Transition asset			1	1
Prior service benefit	22	19	69	54
Net actuarial loss	(125)	(153)	(377)	(471)
Curtailments/Settlements				17
Total before tax	(103)	(134)	(307)	(399)
Tax effect	36	44	104	135
Net of tax	(67)	(90)	(203)	(264)
Cash flow hedging instruments gains (losses)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Total before tax	24	55	104	116
Tax effect	(9)	(20)	(38)	(42)
Net of tax	15	35	66	74
Cash flow hedging instruments gains (losses) | Foreign currency forward/option contracts
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Cost of sales	$ 24	$ 55	105	120
Cash flow hedging instruments gains (losses) | Commodity price swap contracts
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Cost of sales				(2)
Cash flow hedging instruments gains (losses) | Interest rate swap contracts
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense			$ (1)	$ (2)