Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Revenue:
Product	$ 46,005	$ 43,016	$ 113,616	$ 114,289
Service	37,292	33,320	105,601	98,271
Total revenue	83,297	76,336	219,217	212,560
Cost of revenue:
Product	10,731	10,343	27,439	28,002
Service	6,508	5,749	19,273	16,972
Total cost of revenue	17,239	16,092	46,712	44,974
Gross profit	66,058	60,244	172,505	167,586
Operating expenses:
Research and development	13,593	10,145	36,073	29,734
Sales and marketing	27,518	27,022	81,144	77,832
General and administrative	6,564	6,356	20,135	17,478
Amortization of acquired intangible assets	565	476	1,541	1,430
Restructuring charges	372	0	372	0
Total operating expenses	48,612	43,999	139,265	126,474
Income from operations	17,446	16,245	33,240	41,112
Interest and other expense, net:
Interest income	104	210	304	587
Interest expense	(472)	(599)	(1,449)	(1,879)
Other expense, net	(150)	(3)	(607)	(2)
Loss on extinguishment of debt	(690)	0	(690)	0
Total interest and other expense, net	(1,208)	(392)	(2,442)	(1,294)
Income before income tax expense	16,238	15,853	30,798	39,818
Income tax expense	6,207	4,752	11,317	13,324
Net income	$ 10,031	$ 11,101	$ 19,481	$ 26,494
Basic net income per share	$ 0.24	$ 0.26	$ 0.46	$ 0.63
Diluted net income per share	$ 0.24	$ 0.26	$ 0.46	$ 0.62
Weighted average common shares outstanding used in computing:
Net income per share-basic	41,523	42,105	42,126	41,946
Net income per share-diluted	42,303	43,173	42,815	42,836