DIVESTITURES (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 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	$ 141	$ 170	$ 336	$ 341
Divestiture losses/(gains)	9	8	(7)	8
Royalty Income, Nonoperating	(130)	(162)	(288)	(328)
Anagni [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Tangible Asset Impairment Charges		109
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	127	164	280	328
Divestiture losses/(gains)	0	0	0	0
Royalty Income, Nonoperating	(129)	(161)	(256)	(326)
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	7	8
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	10	1	10	3
Divestiture losses/(gains)	0	0	(1)	0
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	1	2	32	2
Divestiture losses/(gains)	9	8	6	8
Royalty Income, Nonoperating	$ (1)	$ (1)	$ (32)	$ (2)

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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