CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Revenue, net	$ 88,879	$ 70,137	$ 302,474	$ 175,813
Cost of goods sold	49,507	46,976	168,348	121,097
Gross profit	39,372	23,161	134,126	54,716
Operating expenses
Research and development	9,190	8,362	24,695	24,572
Sales and marketing	2,551	1,594	6,612	4,884
General and administrative	9,580	6,445	26,188	18,084
Total operating expenses	21,321	16,401	57,495	47,540
Income from operations	18,051	6,760	76,631	7,176
Other income (expense)
Interest income	61	40	166	206
Interest expense	(248)	(462)	(792)	(1,313)
Other income (expense), net	(354)	66	(898)	(532)
Total other income (expense)	(541)	(356)	(1,524)	(1,639)
Income(loss) before income taxes	17,510	6,404	75,107	5,537
Income tax (expense) benefit	1,865	11,332	(6,872)	11,472
Net income (loss)	$ 19,375	$ 17,736	$ 68,235	$ 17,009
Net income (loss) per share basic	$ 1.00	$ 1.03	$ 3.59	$ 1.00
Net income (loss) per share diluted	$ 0.95	$ 0.97	$ 3.39	$ 0.95
Weighted average shares used to compute net income (loss) per share: basic	19,294,022	17,151,031	18,993,068	17,057,687
Weighted average shares used to compute net income (loss)per share: Diluted	20,422,609	18,360,531	20,133,644	17,954,229