Net Loss Per Share - Computation of Net Loss Per Share Attributable to Common Stockholders, Basic and Diluted (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Numerator:
Net loss	$ (50,149)	$ (40,225)	$ (22,541)
Denominator:
Weighted average shares used to compute net loss per share attributable to common stockholder, basic and diluted	25,290	15,596	15,096
Net loss per share-basic and diluted	$ (1.98)	$ (2.58)	$ (1.49)