DIVESTITURES (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 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	$ 173	$ 1,683	$ 509	$ 2,024
Divestiture losses/(gains)	1	(1,179)	(6)	(1,171)
Royalty Income, Nonoperating	(192)	(177)	(480)	(505)
Anagni [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tangible Asset Impairment Charges			113
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	129	163	409	491
Divestiture losses/(gains)	0	0	0	0
Royalty Income, Nonoperating	(148)	(171)	(404)	(497)
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	3	3	10	11
Divestiture losses/(gains)	0	0	0	0
Royalty Income, Nonoperating	0	0	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	0	10	3
Divestiture losses/(gains)	0	1	(1)	1
Royalty Income, Nonoperating	0	0	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
Divestiture losses/(gains)			(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	41	7	73	9
Divestiture losses/(gains)	1	(4)	7	(12)
Royalty Income, Nonoperating	(44)	(6)	(76)	(8)
UPSA
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	1,510	0	1,510
Divestiture losses/(gains)	0	(1,176)	0	(1,160)
Royalty Income, Nonoperating	$ 0	$ 0	$ 0	$ 0

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
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