v3.26.1
Equity - Stock based compensation and stock options (Details)
12 Months Ended
May 31, 2026
item
$ / shares
shares
May 31, 2025
$ / shares
shares
May 31, 2024
$ / shares
shares
2013 Stock Plan      
Stock-Based Compensation      
Total number of shares granted since inception 7,182,579    
Shares available for future grant 1,102,614    
Employee Stock Option      
Stock-Based Compensation      
Expiration term 10 years    
Number of equal annual increments in which stock options are exercisable | item 3    
Commencement period after the date of grant for annual increments of stock options becoming exercisable 1 year    
Granted (in shares) 160,085 157,310 141,545
Weighted average fair value of stock options granted (in dollars per share) | $ / shares $ 28.99 $ 25.51 $ 25.31
Restricted stock | Minimum      
Stock-Based Compensation      
Vesting period 1 year    
Restricted stock | Maximum      
Stock-Based Compensation      
Vesting period 3 years    
Performance Shares      
Stock-Based Compensation      
Vesting period 3 years