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RESTRUCTURING, GOODWILL IMPAIRMENT AND ASSET RELATED CHARGES - NET (2016 Restructuring Charges) (Details) $ in Millions	3 Months Ended									6 Months Ended	12 Months Ended
	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2016 USD ($) employees	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net	$ 249	$ 108	$ 98	$ 165	$ 2,974	$ 139	$ (12)	$ (1)			$ 620	$ 3,100	$ 595
2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									$ 449	$ 449
Charges against the reserve										(153)
Cash payments										(68)	(41)	(153)
Restructuring Reserve	33				68					228	33	68	228
Adjustments to the reserve											6	(7)
Severance and Related Benefit Costs \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Number of Positions Eliminated \| employees									2,500
Restructuring, goodwill impairment and asset related charges - net									$ 268	268
Charges against the reserve										0
Cash payments										(67)	(37)	(150)
Restructuring Reserve	6				51					201	6	51	201
Adjustments to the reserve											(8)	0
Asset Write-downs and Write-offs \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									153	153
Charges against the reserve										(153)
Cash payments										0	0	0
Restructuring Reserve	0				0					0	0	0	0
Adjustments to the reserve											0	0
Costs Associated with Exit and Disposal Activities \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									28	28
Charges against the reserve										0
Cash payments										(1)	(4)	(3)
Restructuring Reserve	$ 27				$ 17					$ 27	27	17	$ 27
Adjustments to the reserve											$ 14	$ (7)
Asset Related Charges and Other, Facility Closing, Write-down of Assets and Write-off of Capital Projects Including In-process Research and Development \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									70
Asset Related Charges and Other, Facility Closing \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									25
Asset Related Charges and Other, Closure and Consolidation of Certain Corporate Facilities and Data Centers \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									25
Asset Related Charges and Other, Facility Closing and Write-down of Non-manufacturing Assets \| 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring, goodwill impairment and asset related charges - net									$ 33