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RESTRUCTURING AND ASSET RELATED CHARGES - NET (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Sep. 30, 2019	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				$ 79	$ 3	$ 74
2017 Restructuring [Member] \| Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				4	3	10
Payments for Restructuring				(16)	(9)
Restructuring Reserve				1	$ 4
2017 Restructuring [Member] \| Impairment of Long-Lived Assets and Other Assets [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges		$ 62
2Q16 Restructuring [Member] \| Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve		$ 0				$ 0
Severance Costs			$ 2
Fair Value, Nonrecurring [Member] \| Manufacturing Assets [Member]
Restructuring Cost and Reserve [Line Items]
Asset Impairment Charges	$ 75			$ 75