Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014
Condensed Consolidated Statements of Income
Revenues	$ 164,856	$ 154,918	$ 328,561	$ 300,609
Cost of revenues	67,428	56,255	134,764	114,841
Gross margin	97,428	98,663	193,797	185,768
Operating expenses:
Research and development	47,465	41,844	94,322	84,329
Selling, general and administrative	40,960	36,017	83,260	70,628
Operating expenses	88,425	77,861	177,582	154,957
Operating income	9,003	20,802	16,215	30,811
Other income (expense):
Interest income	166	200	358	502
Interest expense	(728)	(780)	(1,473)	(1,578)
Other income (expense), net	90	(6)	498	61
Income before income taxes	8,531	20,216	15,598	29,796
Provision for income taxes	956	5,937	1,645	7,407
Net income	$ 7,575	$ 14,279	$ 13,953	$ 22,389
Earnings per share:
Basic (in dollars per share)	$ 0.18	$ 0.33	$ 0.33	$ 0.52
Diluted (in dollars per share)	$ 0.17	$ 0.32	$ 0.32	$ 0.51
Weighted-average common shares outstanding:
Basic (in shares)	42,823	43,462	42,617	43,271
Diluted (in shares)	43,461	44,218	43,305	44,137