Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Plans (Details 6)

v2.4.0.6
Stock-Based Compensation Plans (Details 6) (Restricted Stock Unit [Member], USD $)
In Millions, unless otherwise specified
12 Months Ended
May 31, 2012
May 31, 2011
May 31, 2010
Restricted Stock Unit [Member]
     
Nonvested/unearned shares, other information      
Total intrinsic value of RSUs vested $ 11.0 $ 7.7 $ 4.8
Total grant-date fair value of RSUs vested $ 9.5 $ 8.5 $ 6.6