Computation of Basic and Diluted Net Income (Loss) Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Basic Net Income (Loss) Per Share
Net income (loss)	$ 3,839	$ 1,059	$ 2,130	$ (664)
Weighted average shares used in computing basic net income (loss) per share	40,448	39,260	40,256	38,971
Net income (loss) per share - basic	$ 0.09	$ 0.03	$ 0.05	$ (0.02)
Diluted Net Income (Loss) Per Share
Net income (loss)	$ 3,839	$ 1,059	$ 2,130	$ (664)
Weighted average shares used in computing basic net income (loss) per share	40,448	39,260	40,256	38,971
Effect of dilutive securities	1,791	2,077	1,813
Weighted average shares used in computing diluted net income (loss) per share	42,239	41,337	42,069	38,971
Net income (loss) per share - diluted	$ 0.09	$ 0.03	$ 0.05	$ (0.02)