Quarterly report pursuant to Section 13 or 15(d)

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

v3.5.0.2
Basic and Diluted Earnings Per Share (Narrative) (Details)
shares in Millions, $ in Millions
3 Months Ended
Aug. 31, 2016
USD ($)
item
shares
Aug. 31, 2015
USD ($)
shares
Number of stock repurchase programs | item 2  
Authorized in May 2014 [Member]    
Approved repurchase amount $ 350.0  
Authorized in July 2016 [Member]    
Approved repurchase amount $ 350.0  
Common Stock [Member]    
Common stock issued in connection with exercise or vesting of stock-based awards | shares 1.3 0.7
Common Stock [Member] | Authorized in May 2014 [Member]    
Common shares repurchased and retired | shares   1.3
Common stock repurchased and retired   $ 62.9