REVENUE - Schedule of Disaggregated Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenues	$ 25,472	$ 34,565	$ 77,686	$ 76,099
Total product sales, net
Disaggregation of Revenue [Line Items]
Total revenues	25,997	33,664	77,271	61,974
INDOCIN products
Disaggregation of Revenue [Line Items]
Total revenues	14,541	13,773	42,214	19,207
CAMBIA
Disaggregation of Revenue [Line Items]
Total revenues	5,038	7,449	17,628	21,503
Zipsor
Disaggregation of Revenue [Line Items]
Total revenues	1,999	3,395	6,802	9,261
SPRIX
Disaggregation of Revenue [Line Items]
Total revenues	2,272	5,642	6,911	7,244
Other products
Disaggregation of Revenue [Line Items]
Total revenues	2,147	3,405	3,716	4,759
Commercialization agreement revenue, net
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	11,258
Royalties and milestones
Disaggregation of Revenue [Line Items]
Total revenues	416	299	1,391	1,158
Other revenue
Disaggregation of Revenue [Line Items]
Total revenues	$ (941)	$ 602	$ (976)	$ 1,709