Quarterly report pursuant to Section 13 or 15(d)

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

v3.20.1
Basic and Diluted Earnings Per Share (Narrative) (Details) - USD ($)
shares in Millions, $ in Millions
 1 Months Ended 3 Months Ended 9 Months Ended
May 31, 2019
Feb. 29, 2020
Feb. 28, 2019
Feb. 29, 2020
Feb. 28, 2019
Equity, Class of Treasury Stock [Line Items]          
Common stock repurchased and retired, values       $ 171.9 $ 32.8
Authorized in July 2016 [Member]          
Equity, Class of Treasury Stock [Line Items]          
Common stock repurchased and retired, shares     0.0   0.5
Common stock repurchased and retired, values         $ 32.8
Authorized In May 2019 [Member]          
Equity, Class of Treasury Stock [Line Items]          
Expiration date May 31, 2022        
Common stock repurchased and retired, shares   0.0   2.0  
Common stock repurchased and retired, values       $ 171.9  
Maximum [Member] | Authorized In May 2019 [Member]          
Equity, Class of Treasury Stock [Line Items]          
Approved repurchase amount $ 400.0        
Common Stock [Member]          
Equity, Class of Treasury Stock [Line Items]          
Common stock issued in connection with exercise or vesting of stock-based awards   0.3 0.3 1.4 0.9
Common stock repurchased and retired, shares       2.0 0.5