EMPLOYEE STOCK BENEFIT PLANS Share-based Payment Arrangement, Cost by Plan (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement, Expense	$ 185	$ 56	$ 608	$ 157
Share-based Payment Arrangement, Expense, Tax Benefit	38	10	124	29
Proceeds and Excess Tax Benefit from Share-based Compensation	1		29
Cost of products sold [Member]
Share-based Payment Arrangement, Expense	9	4	28	11
Marketing, selling and administrative [Member]
Share-based Payment Arrangement, Expense	81	32	255	90
Research and development [Member]
Share-based Payment Arrangement, Expense	78	20	261	56
Other (Income)/expense, net [Member]
Share-based Payment Arrangement, Expense	17	$ 0	64	$ 0
Celgene [Member]
Share-based Payment Arrangement, Expense	85		306
Share-based Payment Arrangement, Accelerated Cost	$ 17		64
Celgene [Member] \| Celgene Contingent Value Rights [Member]
Share-based Payment Arrangement, Expense			$ 5

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section S99
-Paragraph 1
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

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