v3.5.0.2
Equity (Stock Option Activity) (Details) - $ / shares
9 Months Ended
Sep. 30, 2016
Dec. 31, 2015
Equity [Abstract]    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value $ 225.54 $ 199.44
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 614,479  
Number of Stock Options [Roll Forward]    
Outstanding, Number of options, Beginning balance 774,551  
Granted, Number of options 150,323  
Exercised, Number of options (135,048)  
Outstanding, Number of options, Ending balance 789,826  
Weighted Average Exercise Price Per Option [Abstract]    
Outstanding, Weighted average exercise price per share, Beginning Balance $ 159.66  
Granted, Weighted average exercise price per share 250.07  
Exercised, Weighted average exercise price per share 146.26  
Outstanding, Weighted average exercise price per share, Ending Balance $ 179.16