Annual report pursuant to Section 13 and 15(d)

Basic and Diluted Earnings Per Share (Narrative) (Details)

v3.19.2
Basic and Diluted Earnings Per Share (Narrative) (Details) - USD ($)
shares in Millions, $ in Millions
 12 Months Ended
May 31, 2019
May 31, 2018
May 31, 2017
Equity, Class of Treasury Stock [Line Items]      
Common stock repurchased and retired, values $ 56.9 $ 143.1 $ 166.2
Authorized in July 2016 [Member]      
Equity, Class of Treasury Stock [Line Items]      
Expiration date May 31, 2019    
Common stock repurchased and retired, shares 0.7 2.5  
Common stock repurchased and retired, values $ 56.9 $ 143.1  
Authorized In May 2019 [Member]      
Equity, Class of Treasury Stock [Line Items]      
Expiration date May 31, 2022    
Maximum [Member] | Authorized in July 2016 [Member]      
Equity, Class of Treasury Stock [Line Items]      
Approved repurchase amount $ 350.0    
Maximum [Member] | Authorized In May 2019 [Member]      
Equity, Class of Treasury Stock [Line Items]      
Approved repurchase amount $ 400.0