Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 30, 2014	Mar. 31, 2013
Revenue
Product	$ 83,569	$ 74,672
Service	7,360	6,220
Total revenue	90,929	80,892
Cost of revenue
Product	17,286	16,464
Service	3,798	2,959
Total cost of revenue	21,084	19,423
Gross margin
Product	66,283	58,208
Service	3,562	3,261
Total gross margin	69,845	61,469
Research, development, and engineering expenses	12,502	11,321
Selling, general, and administrative expenses	34,900	32,167
Operating income	22,443	17,981
Foreign currency loss	(110)	63
Investment income	787	392
Other income (expense)	(273)	117
Income before income tax expense	22,847	18,553
Income tax expense	4,341	2,970
Net income	$ 18,506	$ 15,583
Earnings per weighted-average common and common-equivalent share:
Basic, in dollars per share	$ 0.21	$ 0.18	[1]
Diluted, in dollars per share	$ 0.21	$ 0.18	[1]
Weighted-average common and common-equivalent shares outstanding:
Basic, in shares	86,879	86,522	[1]
Diluted, in shares	89,259	88,260	[1]

[1] Prior period results have been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend which occurred in the third quarter of 2013.