Quarterly report pursuant to Section 13 or 15(d)

Exercise Price for Options Outstanding and Options Exercisable (Detail)

v2.4.0.8
Exercise Price for Options Outstanding and Options Exercisable (Detail) (USD $)
 6 Months Ended
Sep. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Options Outstanding, Number of Shares 3,388,753
Options Exercisable, Number of Shares 489,448
$2.50 - 2.75
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Range of Exercise Price, lower limit $ 2.50
Range of Exercise Price, upper limit $ 2.75
Options Outstanding, Number of Shares 911,000
Options Exercisable, Number of Shares 110,167
Options Outstanding, Weighted Average Exercise Price $ 2.61
Options Exercisable, Weighted Average Exercise Price $ 2.65
Options Outstanding, Weighted Average Remaining Life (Years) 9 years 26 days
Options Exercisable,Weighted Average Remaining Life (Years) 9 years 29 days
$2.76 - 2.85
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Range of Exercise Price, lower limit $ 2.76
Range of Exercise Price, upper limit $ 2.85
Options Outstanding, Number of Shares 372,836
Options Exercisable, Number of Shares 33,180
Options Outstanding, Weighted Average Exercise Price $ 2.83
Options Exercisable, Weighted Average Exercise Price $ 2.83
Options Outstanding, Weighted Average Remaining Life (Years) 9 years 4 days
Options Exercisable,Weighted Average Remaining Life (Years) 9 years 4 days
$3.85
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Exercise Price $ 3.85
Options Outstanding, Number of Shares 112,302
Options Exercisable, Number of Shares 44,146
Options Outstanding, Weighted Average Exercise Price $ 3.85
Options Exercisable, Weighted Average Exercise Price $ 3.85
Options Outstanding, Weighted Average Remaining Life (Years) 8 years 10 months 2 days
Options Exercisable,Weighted Average Remaining Life (Years) 8 years 10 months 2 days
$4.00
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Exercise Price $ 4.00
Options Outstanding, Number of Shares 714,554
Options Exercisable, Number of Shares 85,173
Options Outstanding, Weighted Average Exercise Price $ 4.00
Options Exercisable, Weighted Average Exercise Price $ 4.00
Options Outstanding, Weighted Average Remaining Life (Years) 9 years 6 months 7 days
Options Exercisable,Weighted Average Remaining Life (Years) 8 years 9 months
$4.05 - 4.11
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Range of Exercise Price, lower limit $ 4.05
Range of Exercise Price, upper limit $ 4.11
Options Outstanding, Number of Shares 589,061
Options Exercisable, Number of Shares 34,449
Options Outstanding, Weighted Average Exercise Price $ 4.10
Options Exercisable, Weighted Average Exercise Price $ 4.06
Options Outstanding, Weighted Average Remaining Life (Years) 9 years 7 months 21 days
Options Exercisable,Weighted Average Remaining Life (Years) 8 years 9 months
$4.23 - 4.5
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Range of Exercise Price, lower limit $ 4.23
Range of Exercise Price, upper limit $ 4.5
Options Outstanding, Number of Shares 579,000
Options Exercisable, Number of Shares 152,333
Options Outstanding, Weighted Average Exercise Price $ 4.43
Options Exercisable, Weighted Average Exercise Price $ 4.48
Options Outstanding, Weighted Average Remaining Life (Years) 8 years 10 months 17 days
Options Exercisable,Weighted Average Remaining Life (Years) 8 years 9 months
$4.65 - $5.89
  
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Range of Exercise Price, lower limit $ 4.65
Range of Exercise Price, upper limit $ 5.89
Options Outstanding, Number of Shares 110,000
Options Exercisable, Number of Shares 30,000
Options Outstanding, Weighted Average Exercise Price $ 5.21
Options Exercisable, Weighted Average Exercise Price $ 4.65
Options Outstanding, Weighted Average Remaining Life (Years) 9 years 1 month 28 days
Options Exercisable,Weighted Average Remaining Life (Years) 8 years 5 months 27 days