Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Income Statement [Abstract]
Revenue	$ 68,205	$ 59,938
Cost of revenue	19,908	17,599
Gross profit	48,297	42,339
Operating expenses:
Research and development	10,268	9,471
Sales and marketing	30,802	25,718
General and administrative	9,894	7,415
Acquisition costs and other related charges		149
Total operating expenses	50,964	42,753
Loss from operations	(2,667)	(414)
Interest and other income (expense), net	(29)	71
Loss before income taxes	(2,696)	(343)
Income tax benefit	2,182	561
Net income (loss)	$ (514)	$ 218
Net income (loss) per share:
Basic	$ (0.02)	$ 0.01
Diluted	$ (0.02)	$ 0.01
Weighted average shares outstanding used in computing per share amounts:
Basic	30,630	30,171
Diluted	30,630	31,118