Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Basic Net Income Per Share
Net income	$ 7,735	$ 3,839	$ 16,594	$ 2,130
Weighted average shares used in computing basic net income per share	42,228	40,448	41,963	40,256
Net income per share - basic	$ 0.18	$ 0.09	$ 0.40	$ 0.05
Diluted Net Income Per Share
Net income	$ 7,735	$ 3,839	$ 16,594	$ 2,130
Weighted average shares used in computing basic net income per share	42,228	40,448	41,963	40,256
Effect of dilutive securities	2,694	1,791	2,815	1,813
Weighted average shares used in computing diluted net income per share	44,922	42,239	44,778	42,069
Net income per share - diluted	$ 0.17	$ 0.09	$ 0.37	$ 0.05