CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Net sales	$ 248,234,000	$ 299,255,000	$ 359,111,000
Cost of sales	39,330,000	43,081,000	36,386,000
Gross profit	208,904,000	256,174,000	322,725,000
Operating expenses:
Selling, general and administrative	181,022,000	198,205,000	258,528,000
Investigation, restatement and related	59,465,000	66,504,000	51,322,000
Research and development	11,715,000	11,140,000	15,765,000
Amortization of intangible assets	1,073,000	1,039,000	1,034,000
Impairment of intangible assets	1,027,000	446,000	0
Operating loss	(45,398,000)	(21,160,000)	(3,924,000)
Other (expense) income
Loss on extinguishment of debt	(8,201,000)	0	0
Interest (expense) income, net	(7,941,000)	(4,708,000)	527,000
Other (expense) income, net	(3,000)	283,000	0
Loss before income tax provision	(61,543,000)	(25,585,000)	(3,397,000)
Income tax provision benefit (expense)	12,259,000	5,000	(26,582,000)
Net loss	(49,284,000)	(25,580,000)	(29,979,000)
Net loss available to common stockholders (Note 9)	$ (83,328,000)	$ (25,580,000)	$ (29,979,000)
Net (loss) income per common share - basic (in dollars per share)	$ (0.77)	$ (0.24)	$ (0.28)
Net (loss) income per common share - diluted (in dollars per share)	$ (0.77)	$ (0.24)	$ (0.28)
Weighted average shares outstanding - basic (in shares)	108,257,112	106,946,384	105,596,256
Weighted average shares outstanding - diluted (in shares)	108,257,112	106,946,384	105,596,256