STOCK-BASED COMPENSATION - Cost (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 534	$ 544	$ 468
Income tax benefits	(131)	(179)	(156)
Net stock-based compensation cost	403	364	312
Stock-based compensation cost, unrecognized, related to non-vested awards	$ 851	934
Stock-based compensation cost, unrecognized, related to non-vested awards, weighted average period of recognition	2 years 7 months 6 days
Accounting Standards Update 2016-09, Stock Compensation
Stock-based compensation cost, allocation of recognized costs
Income tax benefits
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	91	88	100
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	384	401	322
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 59	$ 55	51
Other (income) and expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost			$ (6)

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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