Condensed Consolidated Statements of Operations (Unaudited) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Revenue	$ 65,347,000		$ 56,508,000		$ 174,531,000		$ 165,599,000
Cost of revenue (1)	30,053,000	[1]	26,495,000	[1]	80,924,000	[1]	78,004,000	[1]
Gross profit	35,294,000		30,013,000		93,607,000		87,595,000
Operating expenses:
Research and development (1)	12,643,000	[1]	11,967,000	[1]	37,246,000	[1]	35,553,000	[1]
Selling, general and administrative (1)	13,891,000	[1]	11,955,000	[1]	40,941,000	[1]	36,088,000	[1]
Litigation expense (benefit)	104,000		(229,000)		(455,000)		(345,000)
Total operating expenses	26,638,000		23,693,000		77,732,000		71,296,000
Income from operations	8,656,000		6,320,000		15,875,000		16,299,000
Interest and other income (expense), net	(59,000)		156,000		149,000		621,000
Income before income taxes	8,597,000		6,476,000		16,024,000		16,920,000
Income tax provision	1,187,000		555,000		625,000		1,412,000
Net income	7,410,000		5,921,000		15,399,000		15,508,000
Basic net income per share (in Dollars per share)	$ 0.20		$ 0.17		$ 0.42		$ 0.45
Diluted net income per share (in Dollars per share)	$ 0.19		$ 0.16		$ 0.40		$ 0.43
Weighted average common shares outstanding:
Basic (in Shares)	37,910		35,145		37,079		34,677
Diluted (in Shares)	39,009		36,438		38,419		36,008
(1) Includes stock-based compensation expense as follows:
Stock-based compensation	5,231,000		4,182,000		15,081,000		11,326,000
Cost Of Revenue [Member]
(1) Includes stock-based compensation expense as follows:
Stock-based compensation	163,000		112,000		465,000		325,000
Research and Development [Member]
(1) Includes stock-based compensation expense as follows:
Stock-based compensation	1,491,000		1,465,000		4,557,000		4,255,000
Selling, General And Administrative [Member]
(1) Includes stock-based compensation expense as follows:
Stock-based compensation	$ 3,577,000		$ 2,605,000		$ 10,059,000		$ 6,746,000

[1] (1) Includes stock-based compensation expense