Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Revenue	$ 139,761	$ 112,198	[1]	$ 268,911	$ 212,560
Cost of revenue	62,197	50,773		119,852	96,293
Gross profit	77,564	61,425		149,059	116,267
Operating expenses:
Research and development	23,481	20,292		45,091	39,186
Selling, general and administrative	28,561	25,873		55,879	47,965
Litigation expense	640	290		1,171	576
Total operating expenses	52,682	46,455		102,141	87,727
Income from operations	24,882	14,970		46,918	28,540
Interest and other income, net	2,232	1,237		2,673	2,618
Income before income taxes	27,114	16,207		49,591	31,158
Income tax provision	2,908	1,193		3,529	1,668
Net income	$ 24,206	$ 15,014		$ 46,062	$ 29,490
Net income per share:
Basic (in dollars per share)	$ 0.57	$ 0.36		$ 1.09	$ 0.72
Diluted (in dollars per share)	$ 0.55	$ 0.35		$ 1.04	$ 0.68
Weighted-average shares outstanding:
Basic (in shares)	42,237	41,323		42,079	41,185
Diluted (in shares)	44,400	43,397		44,341	43,332
Cash dividends declared per common share (in dollars per share)	$ 0.30	$ 0.20		$ 0.60	$ 0.40

[1] 2017 amounts have not been adjusted under the modified retrospective method.