Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Basic Net Income Per Share
Net income	$ 12,910	$ 8,859
Weighted average shares used in computing basic net income per share	42,811	41,696
Net income per share - basic	$ 0.30	$ 0.21
Diluted Net Income Per Share
Net income	$ 12,910	$ 8,859
Weighted average shares used in computing basic net income per share	42,811	41,696
Effect of dilutive securities	2,367	2,714
Weighted average shares used in computing diluted net income per share	45,178	44,410
Net income per share - diluted	$ 0.29	$ 0.20