RESTRUCTURING CHARGES - Schedule of Restructuring Activities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Equity compensation costs	$ 1,511	$ 3,004	$ 7,038	$ 8,340
Total restructuring costs	268	$ 0	6,787	$ 0
Zyla Life Sciences
Restructuring Cost and Reserve [Line Items]
Employee compensation costs	260		5,695
Equity compensation costs	0		999
Other exit costs	8		93
Total restructuring costs	$ 268		$ 6,787

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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