Current report of foreign issuer pursuant to Rules 13a-16 and 15d-16 Amendments

Stock-Based Compensation Plan (Schedule of Stock Option Activity) (Details)

v2.4.0.8
Stock-Based Compensation Plan (Schedule of Stock Option Activity) (Details) (USD $)
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Number of Options Outstanding    
Shares under option at January 1, 2014 2,007,433  
Granted 4,633  
Exercised (116,609) (292,808)
Forfeited (11,690)  
Shares under option at March 31, 2014 1,883,767  
Shares exercisable under option at March 31, 2014 959,555  
Weighted Average Exercise Price    
Shares under option at January 1, 2014 $ 29.66  
Granted $ 115.12  
Exercised $ 8.61  
Forfeited $ 42.17  
Shares under option at March 31, 2014 $ 31.10  
Shares exercisable under option at March 31, 2014 $ 11.83