CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Net sales	$ 245,015	$ 187,296	$ 118,223
Cost of sales	32,407	20,202	12,665
Gross margin	212,608	167,094	105,558
Operating expenses:
Research and development expenses	12,038	8,413	7,050
Selling, general and administrative expenses	179,997	133,384	90,480
Amortization of intangible assets	2,127	933	928
Operating income	18,446	24,364	7,100
Other expense, net
Interest expense, net	(339)	(86)	(48)
Income before income tax provision	18,107	24,278	7,052
Income tax provision (expense) benefit	(6,133)	5,168	(832)
Net income	$ 11,974	$ 29,446	$ 6,220
Net income per common share - basic (in dollars per share)	$ 0.11	$ 0.28	$ 0.06
Net income per common share - diluted (in dollars per share)	$ 0.11	$ 0.26	$ 0.05
Weighted average shares outstanding - basic (in shares)	105,928,348	105,929,205	105,793,008
Weighted average shares outstanding - diluted (in shares)	112,441,709	113,628,482	113,295,504