Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Net revenues:
Products	$ 71,019	$ 48,175
Service	11,294	11,139
Total net revenues	82,313	59,314
Costs of net revenues:
Cost of products	28,593	25,478
Cost of service	6,154	5,337
Amortization of intangible assets	35	52
Total costs of net revenues	34,782	30,867
Gross profit	47,531	28,447
Operating expenses:
Research and development	10,202	8,694
Selling	9,024	7,938
General and administrative	7,741	6,307
Total operating expenses	26,967	22,939
Income from operations	20,564	5,508
Other income (expense):
Interest income	3	1
Interest expense	(96)	(40)
Other income (expense), net	352	(3)
Total other income (expense), net	259	(42)
Income before income taxes	20,823	5,466
Provision for income taxes	4,442	114
Net income	$ 16,381	$ 5,352
Net income per share:
Basic (in dollars per share)	$ 0.68	$ 0.21
Diluted (in dollars per share)	$ 0.67	$ 0.21
Weighted average shares used in per share calculation:
Basic (in shares)	24,063	25,133
Diluted (in shares)	24,483	25,833