RESTRUCTURING ACTIVITIES (Pre-Tax Restructuring charges) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$ (3)	$ 49
Invigorate Program
Restructuring Cost and Reserve [Line Items]
Employee separation costs	(3)	45	$ 29
Facility-related costs	1	4	1
Asset impairment charges	0	2	3
Total restructuring charges	$ (2)	$ 51	$ 33

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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