Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Net sales	$ 46,713	$ 37,175	$ 91,475	$ 73,360
Cost of products sold and services delivered	15,990	13,961	30,884	27,938
Gross margin	30,723	23,214	60,591	45,422
Operating expenses:
Sales, general and administrative	15,443	13,547	30,008	27,293
Research and development	5,906	3,455	10,464	7,061
Total operating expenses	21,349	17,002	40,472	34,354
Income from operations	9,374	6,212	20,119	11,068
Interest and other income, net	99	42	34	72
Income before provision for income taxes	9,473	6,254	20,153	11,140
Provision for income taxes	3,370	2,370	6,845	3,865
Net income	$ 6,103	$ 3,884	$ 13,308	$ 7,275
Net income per common and common equivalent shares:
Basic (in dollars per share)	$ 0.11	$ 0.07	$ 0.25	$ 0.14
Diluted (in dollars per share)	$ 0.11	$ 0.07	$ 0.24	$ 0.13
Weighted average number of common and common equivalent shares outstanding:
Basic (in shares)	53,644	53,383	53,407	53,287
Diluted (in shares)	54,800	54,755	54,662	54,928
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 6,103	$ 3,884	$ 13,308	$ 7,275
Foreign currency translation adjustments	8	5	97	15
Comprehensive income	$ 6,111	$ 3,889	$ 13,405	$ 7,290