Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted in period		212,000
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted in period	1,000,000	831,000
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures	$ 1.8
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)	3 years
Stock Options | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period, in years	3 years
Stock Options | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period, in years	5 years
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock granted	3,192,502
Vesting period, in years	3 years
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures	$ 4.6
Weighted-average period over which unrecognized compensation expense is expected to be recognized (years)	1 year 7 months 6 days
Time-Based Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock granted		400,000
Performance-Based Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock granted		362,000