Quarterly report pursuant to Section 13 or 15(d)

Description of Stock Plans - Summary of Exercise Price (Details)

v3.19.3
Description of Stock Plans - Summary of Exercise Price (Details)
 6 Months Ended
Sep. 30, 2019
$ / shares
shares
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Options Outstanding, Number of Shares (in shares) | shares 8,724,808
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 2.24
Options Outstanding, Weighted Average Remaining Life 7 years 3 months 10 days
Options Exercisable, Number of Shares (in shares) | shares 4,879,562
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 2.15
$0.00 - 0.50  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 0
Range of exercise price, upper limit (in dollars per share) $ 0.50
Options Outstanding, Number of Shares (in shares) | shares 6,204
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 0.24
Options Outstanding, Weighted Average Remaining Life 5 months 22 days
Options Exercisable, Number of Shares (in shares) | shares 6,204
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 0.24
$0.51 - 1.00  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 0.51
Range of exercise price, upper limit (in dollars per share) $ 1.00
Options Outstanding, Number of Shares (in shares) | shares 1,722,307
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 0.73
Options Outstanding, Weighted Average Remaining Life 7 years 1 month 3 days
Options Exercisable, Number of Shares (in shares) | shares 856,800
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 0.72
$1.01 - 1.50  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 1.01
Range of exercise price, upper limit (in dollars per share) $ 1.5
Options Outstanding, Number of Shares (in shares) | shares 2,108,209
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 1.28
Options Outstanding, Weighted Average Remaining Life 6 years 8 months 20 days
Options Exercisable, Number of Shares (in shares) | shares 1,532,564
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 1.26
$1.51 - 2.00  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 1.51
Range of exercise price, upper limit (in dollars per share) $ 2
Options Outstanding, Number of Shares (in shares) | shares 1,074,723
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 1.66
Options Outstanding, Weighted Average Remaining Life 8 years 5 months 22 days
Options Exercisable, Number of Shares (in shares) | shares 446,746
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 1.65
$2.01 - 2.50  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 2.01
Range of exercise price, upper limit (in dollars per share) $ 2.50
Options Outstanding, Number of Shares (in shares) | shares 568,851
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 2.22
Options Outstanding, Weighted Average Remaining Life 8 years 6 months 8 days
Options Exercisable, Number of Shares (in shares) | shares 211,287
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 2.21
$2.51 - 3.00  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 2.51
Range of exercise price, upper limit (in dollars per share) $ 3.00
Options Outstanding, Number of Shares (in shares) | shares 540,000
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 2.59
Options Outstanding, Weighted Average Remaining Life 4 years 7 months 7 days
Options Exercisable, Number of Shares (in shares) | shares 540,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 2.59
$3.51 - 4.00  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 3.51
Range of exercise price, upper limit (in dollars per share) $ 4.00
Options Outstanding, Number of Shares (in shares) | shares 1,897,514
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 3.89
Options Outstanding, Weighted Average Remaining Life 8 years 3 months 22 days
Options Exercisable, Number of Shares (in shares) | shares 665,627
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 3.94
$4.01 - 4.50  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 4.01
Range of exercise price, upper limit (in dollars per share) $ 4.50
Options Outstanding, Number of Shares (in shares) | shares 505,000
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 4.14
Options Outstanding, Weighted Average Remaining Life 5 years 22 days
Options Exercisable, Number of Shares (in shares) | shares 505,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 4.14
$4.51 - 5.00  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Range of exercise price, lower limit (in dollars per share) 4.51
Range of exercise price, upper limit (in dollars per share) $ 5.00
Options Outstanding, Number of Shares (in shares) | shares 60,000
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 4.65
Options Outstanding, Weighted Average Remaining Life 3 years 5 months 25 days
Options Exercisable, Number of Shares (in shares) | shares 60,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 4.65
$5.01 and over  
Employee Stock Ownership Plan E S O P Disclosures [Line Items]  
Exercise price (in dollars per share) $ 5.01
Options Outstanding, Number of Shares (in shares) | shares 242,000
Options Outstanding, Weighted Average Exercise Price (in dollars per share) $ 5.64
Options Outstanding, Weighted Average Remaining Life 8 years 10 months
Options Exercisable, Number of Shares (in shares) | shares 55,334
Options Exercisable, Weighted Average Exercise Price (in dollars per share) $ 5.86