Computation of Basic and Diluted Net Income Loss Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Basic Net (Loss) Income Per Share
Net (loss) income	$ (1,723)	$ 3,119
Weighted average shares used in computing basic net (loss) income per share	38,678	39,144
Net (loss) income per share - basic	$ (0.04)	$ 0.08
Diluted Net (Loss) Income Per Share
Net (loss) income	$ (1,723)	$ 3,119
Weighted average shares used in computing basic net (loss) income per share	38,678	39,144
Effect of dilutive securities		2,405
Weighted average shares used in computing diluted net (loss) income per share	38,678	41,549
Net (loss) income per share - diluted	$ (0.04)	$ 0.08