RESTRUCTURING SCHEDULE OF RESTRUCTURING RESERVE (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Jan. 01, 2021	Jan. 01, 2020
Restructuring Liability	$ 126	$ 141	$ 148	$ 100
Change in estimates	(1)	(4)
Restructuring Charges Exclude Accelerated Stock-Based Compensation	39	142
Provision for restructuring	45	160
Foreign currency translation and other	(2)	6
Payments	(59)	(107)
Celgene Integration [Member] \| Accelerated Stock Based Compensation [Member]
Provision for restructuring	$ 6	$ 18

Restructuring Charges Excluding Accelerated Stock-based Compensation

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments 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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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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