DISPOSITIONS - Sale of Gralise (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Jan. 10, 2020	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Co-promotion service income			$ (3,225)	$ 3,948
Gralise | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received, including base purchase price and inventory adjustment	$ 78,600
Consideration received, base purchase price	75,000
Consideration received, inventory adjustment upon disposal	$ 3,600
Consideration receivable as percentage of net sales after closing	75.00%
Threshold for consideration receivable on net sales after closing	$ 70,000
Gain (loss) on sale			(900)
Contingent consideration, payments received			$ 51,600
Gain (loss) on disposal		$ 126,600
Net sale after closing, contingent consideration	$ 51,600
Co-promotion service income		$ 1,300