Oct 23                           
            2015                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $222,450               
              $74.15 p/Share               
          
        
            
        
          
              3,000 
              Reduced 21.2% 
          
   
         
        
          
            11,149  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 11                           
            2015                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $58,840               
              $87.56 p/Share               
          
        
            
        
          
              672 
              Reduced 4.53% 
          
   
         
        
          
            14,149  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 10                           
            2015                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $62,154               
              $87.05 p/Share               
          
        
            
        
          
              714 
              Reduced 4.6% 
          
   
         
        
          
            14,821  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 10                           
            2015                           
          
        
          
            
              BUY 
            
            
                Grant, award, or other acquisition 
            
                            
         
        
          
              $300,671               
              $87.05 p/Share               
          
        
            
        
          
              3,454 
              Added 18.19% 
          
   
         
        
          
            15,535  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 09                           
            2015                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $42,554               
              $90.54 p/Share               
          
        
            
        
          
              470 
              Reduced 3.74% 
          
   
         
        
          
            12,081  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 07                           
            2015                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $45,340               
              $90.5 p/Share               
          
        
            
        
          
              501 
              Reduced 3.84% 
          
   
         
        
          
            12,551  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 05                           
            2015                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $24,631               
              $92.25 p/Share               
          
        
            
        
          
              267 
              Reduced 2.0% 
          
   
         
        
          
            13,052  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 04                           
            2015                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $26,409               
              $92.34 p/Share               
          
        
            
        
          
              286 
              Reduced 2.1% 
          
   
         
        
          
            13,319  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Feb 17                           
            2015                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $43,139               
              $93.78 p/Share               
          
        
            
        
          
              460 
              Reduced 3.27% 
          
   
         
        
          
            13,605  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Feb 16                           
            2015                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $43,980               
              $92.98 p/Share               
          
        
            
        
          
              473 
              Reduced 3.25% 
          
   
         
        
          
            14,065  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Jan 23                           
            2015                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $671,905               
              $88.56 p/Share               
          
        
            
        
          
              7,587 
              Reduced 34.29% 
          
   
         
        
          
            14,538  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Jan 21                           
            2015                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $416,523               
              $87.56 p/Share               
          
        
            
        
          
              4,757 
              Reduced 17.7% 
          
   
         
        
          
            22,125  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Jan 21                           
            2015                           
          
        
          
            
              BUY 
            
            
                Grant, award, or other acquisition 
            
                            
         
        
          
              $1,080,841               
              $87.56 p/Share               
          
        
            
        
          
              12,344 
              Added 31.47% 
          
   
         
        
          
            26,882  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Oct 17                           
            2014                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $201,521               
              $103.61 p/Share               
          
        
            
        
          
              1,945 
              Reduced 11.8% 
          
   
         
        
          
            14,538  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Jul 18                           
            2014                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $214,942               
              $110.51 p/Share               
          
        
            
        
          
              1,945 
              Reduced 10.55% 
          
   
         
        
          
            16,483  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Apr 21                           
            2014                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $565,469               
              $93.02 p/Share               
          
        
            
        
          
              6,079 
              Reduced 24.81% 
          
   
         
        
          
            18,428  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 08                           
            2014                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $32,741               
              $88.49 p/Share               
          
        
            
        
          
              370 
              Reduced 1.49% 
          
   
         
        
          
            24,507  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 07                           
            2014                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $31,856               
              $88.49 p/Share               
          
        
            
        
          
              360 
              Reduced 1.43% 
          
   
         
        
          
            24,877  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 04                           
            2014                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $28,966               
              $90.52 p/Share               
          
        
            
        
          
              320 
              Reduced 1.25% 
          
   
         
        
          
            25,237  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Mar 04                           
            2014                           
          
        
          
            
              BUY 
            
            
                Grant, award, or other acquisition 
            
                            
         
        
          
              $228,201               
              $90.52 p/Share               
          
        
            
        
          
              2,521 
              Added 8.98% 
          
   
         
        
          
            25,556  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Feb 16                           
            2014                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $28,742               
              $83.31 p/Share               
          
        
            
        
          
              345 
              Reduced 1.48% 
          
   
         
        
          
            23,035  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Jan 22                           
            2014                           
          
        
          
            
              SELL 
            
            
                Payment of exercise price or tax liability 
            
                            
         
        
          
              $200,303               
              $81.59 p/Share               
          
        
            
        
          
              2,455 
              Reduced 9.5% 
          
   
         
        
          
            23,380  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Jan 22                           
            2014                           
          
        
          
            
              BUY 
            
            
                Grant, award, or other acquisition 
            
                            
         
        
          
              $528,458               
              $81.59 p/Share               
          
        
            
        
          
              6,477 
              Added 20.05% 
          
   
         
        
          
            25,835  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Nov 18                           
            2013                           
          
        
          
            
              SELL 
            
            
                Open market or private sale 
            
                            
         
        
          
              $154,912               
              $68.85 p/Share               
          
        
            
        
          
              2,250 
              Reduced 10.41% 
          
   
         
        
          
            19,358  
            Common Stock 
          
          
        
          
             
           
                
        
      
      
        
            Nov 15                           
            2013                           
          
        
          
            
              BUY 
            
            
                Grant, award, or other acquisition 
            
                            
         
        
          
              $181,558               
              $68.59 p/Share               
          
        
            
        
          
              2,647 
              Added 10.91% 
          
   
         
        
          
            21,608  
            Common Stock