Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Plans (Details 7)

v2.4.0.8
Stock-Based Compensation Plans (Details 7) (Restricted Stock Awards [Member], USD $)
In Millions, except Per Share data, unless otherwise specified
12 Months Ended
May 31, 2013
May 31, 2012
May 31, 2011
Restricted Stock Awards [Member]
     
Non-vested/unearned shares activity      
Nonvested/unearned shares outstanding, Beginning balance 0.2    
Nonvested/unearned shares, Beginning balance, Weighted-average grant-date fair value per share $ 29.35    
Granted 0.1    
Granted, Weighted-average grant-date fair value per share $ 31.76 $ 30.69 $ 26.40
Vested (0.1)    
Vested, Weighted-average grant-date fair value per share $ 31.06    
Forfeited 0    
Forfeited, Weighted-average grant-date fair value per share $ 29.19    
Nonvested/unearned shares, Ending Balance 0.2 0.2  
Nonvested/unearned shares, Ending balance, Weighted-average grant-date fair value per share $ 29.83 $ 29.35