CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues:
Product revenues	$ 85,244	$ 75,581	$ 167,824	$ 144,817
Services and other revenues	19,808	18,105	38,992	35,979
Total revenues	105,052	93,686	206,816	180,796
Cost of revenues:
Cost of product revenues	41,003	36,286	79,903	69,833
Cost of services and other revenues	8,009	8,032	16,378	16,228
Total cost of revenues	49,012	44,318	96,281	86,061
Gross profit	56,040	49,368	110,535	94,735
Operating expenses:
Research and development	6,471	7,150	12,592	15,104
Selling, general and administrative	37,011	32,859	75,431	66,104
Total operating expenses	43,482	40,009	88,023	81,208
Income from operations	12,558	9,359	22,512	13,527
Interest and other income (expense), net	(40)	63	(296)	(159)
Income before provision for income taxes	12,518	9,422	22,216	13,368
Provision for income taxes	4,729	3,406	8,233	3,967
Net income	$ 7,789	$ 6,016	$ 13,983	$ 9,401
Net income per share:
Net income per share-basic (in dollars per share)	$ 0.22	$ 0.17	$ 0.39	$ 0.28
Net income per share - diluted (in dollars per share)	$ 0.21	$ 0.17	$ 0.38	$ 0.27
Weighted average shares outstanding:
Basic (in shares)	35,661	34,450	35,451	34,177
Diluted (in shares)	36,618	35,374	36,478	35,099