Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Total revenue	$ 40,003	$ 34,306	$ 105,466	$ 86,025
Cost of revenue:
Total cost of revenue	16,517	13,062	44,041	36,449
Gross profit	23,486	21,244	61,425	49,576
Operating expenses:
Research and development	2,405	2,863	7,803	7,744
Selling, general and administrative	15,231	16,385	46,101	46,407
Total operating expenses	17,636	19,248	53,904	54,151
Operating income (loss)	5,850	1,996	7,521	(4,575)
Interest expense	(782)	(1,097)	(2,810)	(2,470)
Other income (expense)	(72)	144	104	323
Net income (loss)	$ 4,996	$ 1,043	$ 4,815	$ (6,722)
Net income (loss) per common share, basic and diluted	$ 0.03	$ 0.01	$ 0.03	$ (0.04)
Weighted average common shares outstanding:
Basic	166,375	163,119	165,838	162,109
Diluted	169,655	168,503	169,759	162,109
Product sales [Member]
Revenue:
Total revenue	$ 28,947	$ 24,687	$ 80,709	$ 63,607
Cost of revenue:
Total cost of revenue	13,615	12,510	38,556	33,791
Licensing and Development Revenue [Member]
Revenue:
Total revenue	4,321	1,211	8,763	4,365
Royalties [Member]
Revenue:
Total revenue	6,735	8,408	15,994	18,053
Cost of development revenue [Member]
Cost of revenue:
Total cost of revenue	$ 2,902	$ 552	$ 5,485	$ 2,658