EMPLOYEE STOCK BENEFIT PLANS Share-based Payment Arrangement, Cost by Plan (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement, Expense	$ 210	$ 53
Share-based Payment Arrangement, Expense, Tax Benefit	46	10
Proceeds and Excess Tax Benefit from Share-based Compensation	23	2
Cost of Sales [Member]
Share-based Payment Arrangement, Expense	10	4
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense	88	30
Research and Development Expense [Member]
Share-based Payment Arrangement, Expense	94	19
Other Income [Member]
Share-based Payment Arrangement, Expense	18	$ 0
Celgene [Member]
Share-based Payment Arrangement, Expense	123
Share-based Payment Arrangement, Accelerated Cost	18
Contingent Value Rights [Member] \| Share-based Payment Arrangement, Option [Member] \| Celgene [Member]
Share-based Payment Arrangement, Expense	$ 9

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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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