ACQUISITIONS AND OTHER ARRANGEMENTS - Summary of Fair Value of Assets Acquired and Liabilities Assumed for Claris Injectables Limited (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jul. 27, 2017
Acquisitions And Collaborations [Line Items]
Goodwill	$ 3,030	$ 2,937	$ 2,929	$ 3,002	$ 2,978	$ 2,981	$ 3,103	$ 3,102
Claris Injectables Limited [Member]
Acquisitions And Collaborations [Line Items]
Cash									$ 11
Accounts receivable, net									16
Inventories									30
Prepaid expenses and other current assets									16
Property, plant and equipment									130
Goodwill									296
Other intangible assets									280
Other non-current assets									20
Accounts payable and accrued liabilities									23
Other non-current liabilities									136
Total assets acquired and liabilities assumed									$ 640