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SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions		12 Months Ended
SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions	Jan. 21, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Total consideration		$ 63	$ 440	$ 587
Goodwill		$ 6,619	$ 6,563	$ 6,335
Customer Relationships
Subsequent Event [Line Items]
Finite-lived intangible asset, useful life		18 years
Subsequent Event \| Blueprint Genetics Oy
Subsequent Event [Line Items]
Total consideration	$ 110
Finite-lived intangibles	40
Goodwill	$ 70