Quarterly report pursuant to Section 13 or 15(d)

Stock Options and Warrants - Activity (Detail)

v3.21.1
Stock Options and Warrants - Activity (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 9 Months Ended 12 Months Ended
Feb. 28, 2021
May 31, 2020
Stock option and warrant activity    
Options and warrants outstanding, Number of Shares 131,361,000  
Granted, Number of Shares 5,836,000  
Exercised, Number of Shares (73,358,000)  
Forfeited/expired/cancelled, Number of Shares (648,000)  
Options and warrants outstanding, Number of Shares 63,191,000 131,361,000
Outstanding exercisable, Number of Shares 57,042,000  
Options and warrants outstanding, Weighted Average Exercise Price $ 0.65  
Granted, Weighted Average Exercise Price 3.72  
Exercised, Weighted Average Exercise Price 0.58  
Forfeited/expired/cancelled, Weighted Average Exercise Price 1.10  
Options and warrants outstanding, Weighted Average Exercise Price 0.92 $ 0.65
Outstanding exercisable, Weighted Average Exercise Price $ 0.75  
Options and warrants outstanding, Weighted Average Remaining Contractual Life in Years 4 years 5 months 26 days 5 years 9 months 14 days
Outstanding exercisable, Weighted Average Remaining Contractual Life in Years 4 years 1 month 6 days  
Options and warrants outstanding, Aggregate Intrinsic Value $ 227,079 $ 302,961
Outstanding exercisable, Aggregate Intrinsic Value $ 216,042