Stock-Based Compensation - Schedule of Weighted Average Assumptions used in Black-Scholes Valuation Model for Stock Options Granted (Detail)	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Expected volatility		75.40%	85.50%	75.10%
Risk-free interest rate		1.70%	1.90%	1.70%
Expected life (years)		5 years 9 months 18 days	5 years 9 months 18 days	5 years 10 months 24 days
Dividend yield	0.00%	0.00%	0.00%	0.00%