Quarterly report pursuant to Section 13 or 15(d)

Equity Awards and Warrants - Expense and unrecognized (Details)

v3.21.4
Equity Awards and Warrants - Expense and unrecognized (Details) - USD ($)
$ / shares in Units, $ in Thousands, shares in Millions
3 Months Ended 6 Months Ended
Nov. 30, 2021
Nov. 30, 2020
Nov. 30, 2021
Nov. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Compensation expense     $ 4,657 $ 7,115
Equity instruments issued in legal settlement, shares     1.6  
Warrants for legal settlement, expiration period     7 years  
Warrants for legal settlement, exercise price     $ 0.40  
Stock Options And Warrants [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Compensation expense $ 2,100 $ 4,700 $ 3,400 $ 5,500