Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Revenue:
Product	$ 44,010	$ 44,662
Service	25,557	22,549
Total revenue	69,567	67,211
Cost of revenue:
Product	10,604	10,707
Service	2,706	2,082
Total cost of revenue	13,310	12,789
Gross profit	56,257	54,422
Operating expenses:
Research and development	20,149	15,358
Sales and marketing	33,441	27,657
General and administrative	9,055	7,995
Total operating expenses	62,645	51,010
Income (loss) from operations	(6,388)	3,412
Interest income	356	207
Other expense, net	(117)	(69)
Income (loss) before income tax provision	(6,149)	3,550
Income tax benefit (provision)	3,912	(579)
Deferred Tax Assets, Net of Valuation Allowance	6,600
Net income (loss)	$ (2,237)	$ 2,971
Net income (loss) per share:
Basic (in dollars per share)	$ (0.06)	$ 0.09
Diluted (in dollars per share)	$ (0.06)	$ 0.08
Weighted average shares used in computing net income (loss) per share:
Basic (in shares)	36,563	34,633
Diluted (in shares)	36,563	36,546
Deferred Tax Assets, Valuation Allowance	$ 500