Supplemental Equity and Comprehensive Income Information - Reclass AOCI (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Amount Reclassified from Accumulated Other Comprehensive Income
Net of tax	$ (135)	$ (75)	$ (277)	$ (146)
Gains (losses) associated with defined benefit pension and postretirement plans amortization
Amount Reclassified from Accumulated Other Comprehensive Income
Prior service benefit	19	22	38	44
Net actuarial loss	(170)	(141)	(340)	(282)
Total before tax	(151)	(119)	(302)	(238)
Tax effect	37	41	72	77
Net of tax	(114)	(78)	(230)	(161)
Cash flow hedging instruments gains (losses)
Amount Reclassified from Accumulated Other Comprehensive Income
Total before tax	(28)	5	(62)	23
Tax effect	7	(2)	15	(8)
Net of tax	(21)	3	(47)	15
Cash flow hedging instruments gains (losses) \| Foreign currency forward/option contracts
Amount Reclassified from Accumulated Other Comprehensive Income
Cost of sales	(27)	$ 5	(61)	$ 23
Cash flow hedging instruments gains (losses) \| Interest rate swap contracts
Amount Reclassified from Accumulated Other Comprehensive Income
Cost of sales	$ (1)		$ (1)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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