Post-effective amendment to a registration statement that is not immediately effective upon filing

Equity Awards and Warrants - Stock options (Details)

v3.23.3
Equity Awards and Warrants - Stock options (Details) - Stock Options - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
12 Months Ended
May 31, 2023
May 31, 2022
May 31, 2021
Number of shares      
Outstanding, beginning of period 17,457 17,839  
Granted 12,417 11,985  
Exercised   (510)  
Forfeited, expired, and cancelled (10,051) (11,857)  
Outstanding, end of period 19,823 17,457 17,839
Options exercisable (in shares) 11,932    
Weighted average exercise price      
Outstanding at the beginning of the year (in dollars per share) $ 1.53 $ 1.58  
Granted 0.41 1.38  
Exercised   0.79  
Forfeited, expired, and cancelled 1.16 1.51  
Outstanding at the end of the year (in dollars per share) 0.99 $ 1.53 $ 1.58
Options outstanding and exercisable $ 1.21    
Additional Information      
Weighted average remaining contractual life in years 7 years 10 months 13 days 7 years 9 months 14 days 7 years 11 months 4 days
Weighted average remaining contractual life in years exercisable 7 years 7 days    
Aggregate intrinsic value   $ 301 $ 15,390