DIVESTITURES (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses, Net of Cash Divested	$ 195	$ 171
Disposal Group, Not Discontinued Operation, (Gain) Loss on Disposal	(16)	0
Royalty Income, Nonoperating	(158)	(166)
Diabetes business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses, Net of Cash Divested	153	164
Disposal Group, Not Discontinued Operation, (Gain) Loss on Disposal	0	0
Royalty Income, Nonoperating	(127)	(165)
Erbitux [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses, Net of Cash Divested	4	5
Disposal Group, Not Discontinued Operation, (Gain) Loss on Disposal	0	0
Royalty Income, Nonoperating	0	0
Manufacturing Facility [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses, Net of Cash Divested	0	2
Disposal Group, Not Discontinued Operation, (Gain) Loss on Disposal	(1)	0
Royalty Income, Nonoperating	0	0
Avapro, Avalide, and Plavix [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses, Net of Cash Divested	7	0
Disposal Group, Not Discontinued Operation, (Gain) Loss on Disposal	(12)	0
Royalty Income, Nonoperating	0	0
Other divestitures [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Businesses, Net of Cash Divested	31	0
Disposal Group, Not Discontinued Operation, (Gain) Loss on Disposal	(3)	0
Royalty Income, Nonoperating	$ (31)	$ (1)

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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+ References

No definition available.

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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- Definition

Ancillary revenue earned during the period from the consideration paid to the entity for the use of its rights and property by another party. Examples include licensing the use of copyrighted materials and leasing the extraction of natural resources.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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