Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Plans (Details 2)

v2.4.0.6
Stock-Based Compensation Plans (Details 2) (Employee Stock Option [Member], USD $)
In Millions, except Per Share data, unless otherwise specified
 12 Months Ended
May 31, 2012
Y
May 31, 2011
May 31, 2010
Employee Stock Option [Member]
      
Stock option activity      
Options outstanding, Beginning Balance, Shares 12.5 14.2 14.0
Options outstanding, Beginning balance, Weighted-average exercise price per share $ 34.14 $ 34.31 $ 34.84
Options Granted 0.8 0.5 1.4
Options granted, Weighted-average exercise price per share $ 30.88 $ 26.83 $ 26.34
Options exercised (0.2) (0.4) (0.4)
Options exercised, Weighted-average exercise price per share $ 27.85 $ 28.58 $ 23.12
Options forfeited (0.3) (0.8) (0.4)
Options forfeited, Weighted-average exercise price per share $ 29.45 $ 29.68 $ 33.35
Options expired (2.8) (1.0) (0.4)
Options expired, Weighted-average exercise price per share $ 35.19 $ 39.41 $ 36.18
Options outstanding, Ending balance, Shares 10.0 12.5 14.2
Options outstanding, Ending balance, Weighted-average exercise price per share $ 33.88 $ 34.14 $ 34.31
Options outstanding, Ending balance, Weighted-average remaining contractual term 4.3    
Options outstanding, Ending balance, Aggregate intrinsic value $ 4.8    
Options exercisable, Ending balance, Shares 8.4    
Options exercisable, Ending balance, Weighted-average exercise price per share $ 34.71    
Options exercisable, Ending balance, Weighted-average remaining contractual term 3.6    
Options exercisable, Ending balance, Aggregate intrinsic value $ 2.1