Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Condensed Consolidated Statements of Income
Revenues	$ 156,194	$ 158,144	$ 484,755	$ 458,753
Cost of revenues	62,759	62,033	197,523	176,874
Gross margin	93,435	96,111	287,232	281,879
Operating expenses:
Research and development	46,483	42,517	140,805	126,846
Selling, general and administrative	35,729	43,990	118,989	114,618
Operating expenses	82,212	86,507	259,794	241,464
Operating income	11,223	9,604	27,438	40,415
Other income (expense):
Interest income	186	231	544	733
Interest expense	(687)	(768)	(2,160)	(2,346)
Other income (expense), net	(280)	42	218	103
Income before income taxes	10,442	9,109	26,040	38,905
Provision for income taxes	467	3,501	2,112	10,908
Net income	$ 9,975	$ 5,608	$ 23,928	$ 27,997
Earnings per share:
Basic (in dollars per share)	$ 0.24	$ 0.13	$ 0.56	$ 0.65
Diluted (in dollars per share)	$ 0.23	$ 0.13	$ 0.55	$ 0.64
Weighted-average common shares outstanding:
Basic (in shares)	42,331	43,112	42,522	43,218
Diluted (in shares)	42,795	43,815	43,135	44,030