Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Plans (Restricted Stock Awards Activity) (Details)

v3.20.2
Stock-Based Compensation Plans (Restricted Stock Awards Activity) (Details) - $ / shares
shares in Millions
12 Months Ended
May 31, 2020
May 31, 2019
May 31, 2018
Time-Based Restricted Stock Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Nonvested, Beginning balance 0.1    
Granted 0.1    
Vested (0.1)    
Forfeited    
Nonvested, Ending balance 0.1 0.1  
Nonvested, Beginning balance, Weighted-average grant-date fair value per share $ 64.32    
Granted, Weighted-average grant-date fair value per share 84.46 $ 69.80 $ 57.50
Vested, Weighted-average grant-date fair value per share 63.63    
Forfeited, Weighted-average grant-date fair value per share 73.82    
Nonvested, Ending balance, Weighted-average grant-date fair value per share $ 73.20 $ 64.32  
Performance-Based Restricted Stock Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Nonvested, Beginning balance 0.4    
Granted [1]    
Vested (0.1)    
Forfeited    
Nonvested, Ending balance 0.3 0.4  
Nonvested, Beginning balance, Weighted-average grant-date fair value per share $ 58.09    
Granted, Weighted-average grant-date fair value per share 80.59 [1] $ 65.17 $ 53.08
Vested, Weighted-average grant-date fair value per share 56.97    
Forfeited, Weighted-average grant-date fair value per share 63.07    
Nonvested, Ending balance, Weighted-average grant-date fair value per share $ 61.97 $ 58.09  
[1] For performance-based shares, granted number assumes achievement of performance goals at target. Actual number of shares to be earned may differ from this amount.