Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Sales:
Product	$ 90,295	$ 90,677	$ 85,136
Service	71,993	46,435	27,400
Net sales	162,288	137,112	112,536
Costs and expenses:
Costs of product sales	51,518	51,775	46,598
Costs of service sales	45,058	30,363	20,970
Research and development	12,987	12,147	11,548
Sales, marketing and support	28,792	24,069	23,473
General and administrative	17,764	12,188	10,555
Total costs and expenses	156,119	130,542	113,144
Income (loss) from operations	6,169	6,570	(608)
Interest income	657	510	297
Interest expense	637	323	223
Other income	494	86	910
Income before income tax expense (benefit)	6,683	6,843	376
Income tax expense (benefit)	2,150	3,263	(484)
Net income	$ 4,533	$ 3,580	$ 860
Per share information:
Net income per share, basic (in dollars per share)	$ 0.30	$ 0.24	$ 0.06
Net income per share, diluted (in dollars per share)	$ 0.30	$ 0.24	$ 0.06
Number of shares used in per share calculation:
Basic (in shares)	15,144	14,777	14,768
Diluted (in shares)	15,341	15,019	15,072