RESTRUCTURING, INTEGRATION AND SEPARATION COSTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Cost-rationalization and integration initiatives
Restructuring, integration and separation costs	$ 12	$ 4
Selling, general and administrative	606	633
Restructuring and Integration Costs
Cost-rationalization and integration initiatives
Liabilities associated with restructuring, integration and separation costs	18
Costs incurred	3	4
Facility closure costs	2	3
Severance costs	1
Restructuring payments	5	4
Other severance costs		1
Separation Costs
Cost-rationalization and integration initiatives
Restructuring, integration and separation costs	9	0
Selling, general and administrative	$ 20	$ 0

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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