Shareholders' Equity (Tables)
12 Months Ended
Jan. 31, 2012
Shareholders' Equity [Abstract]  
Company's Common Share Repurchase And Issuance Activity
     Shares     Weighted-
average
price per
share
 

Treasury stock balance at January 31, 2010

     7,776,419      $ 35.90   

Shares of common stock repurchased under share repurchase programs

     5,084,770        39.33   

Shares of treasury stock reissued

     (343,651 )   
  

 

 

   

Treasury stock balance at January 31, 2011

     12,517,538        37.28   

Shares of common stock repurchased under share repurchase programs

     6,736,436        46.74   

Shares of treasury stock reissued

     (1,087,213 )   
  

 

 

   

Treasury stock balance at January 31, 2012

     18,166,761        40.71