Disaggregated Revenues - Summary of Revenues (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	$ 148,464	$ 155,135	$ 420,725	$ 376,840
Net product sales
Disaggregation of Revenue [Line Items]
Total revenues	145,532	152,133	412,541	368,607
Trokendi XR
Disaggregation of Revenue [Line Items]
Total revenues	80,935	82,906	231,531	241,131
Oxtellar XR
Disaggregation of Revenue [Line Items]
Total revenues	29,728	28,364	82,120	75,983
APOKYN
Disaggregation of Revenue [Line Items]
Total revenues	24,627	34,482	73,338	43,082
MYOBLOC
Disaggregation of Revenue [Line Items]
Total revenues	4,596	4,050	13,477	5,279
XADAGO
Disaggregation of Revenue [Line Items]
Total revenues	3,276	2,331	9,390	3,132
Qelbree
Disaggregation of Revenue [Line Items]
Total revenues	2,370	0	2,685	0
Royalty revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 2,932	$ 3,002	$ 8,184	$ 8,233