RESTRUCTURING CHARGES - Schedule of Restructuring Activities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Equity compensation costs	$ 3,593	$ 2,634	$ 5,527	$ 5,336
Total restructuring costs	6,519	$ 0	6,519	$ 0
Zyla Life Sciences
Restructuring Cost and Reserve [Line Items]
Employee compensation costs	5,435		5,435
Equity compensation costs	999		999
Other exit costs	85		85
Total restructuring costs	$ 6,519		$ 6,519

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

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