v2.4.0.6

Summary of Changes of Non-Vested Options (Detail) (USD $) | 12 Months Ended
--- | ---
Mar. 31, 2013
Number of options |
Nonvested, Number of Options, Beginning Balance | 110,037
Number of Options, Vested | (110,037)
Weighted average grant-date fair value |
Weighted Average Grant-Date Fair Value, Nonvested, Beginning Balance | $ 7.87
Weighted Average Grant-Date Fair Value, Vested | $ 7.87

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