Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Plans (Details 2)

v2.4.0.8
Stock-Based Compensation Plans (Details 2) (Employee Stock Option [Member], USD $)
In Millions, unless otherwise specified
12 Months Ended
May 31, 2014
May 31, 2013
May 31, 2012
Employee Stock Option [Member]
     
Stock options, other information      
Total intrinsic value of stock options exercised $ 18.9 $ 7.8 $ 0.8
Total grant-date fair value of stock options vested $ 3.0 $ 3.0 $ 10.4