v2.4.0.6
Stock Options (Details) (USD $)
6 Months Ended
Jun. 30, 2013
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Option, outstanding number 69,480 82,272
Option exercisable, contractual term 8 years 4 months 24 days  
Option, exercisable number 48,015  
Options Exercise Price 54.00 [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options, exercise price $ 54.00  
Option, outstanding number 167  
Option exercisable, contractual term 0 years  
Option, exercisable number 0  
Options Exercise Price 60.00 [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options, exercise price $ 60.00  
Option, outstanding number 167  
Option exercisable, contractual term 0 years  
Option, exercisable number 0  
Options Exercise Price 66.00 [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options, exercise price $ 66.00  
Option, outstanding number 250  
Option exercisable, contractual term 0 years  
Option, exercisable number 0  
Options Exercise Price 103.50 [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options, exercise price $ 103.50  
Option, outstanding number 57,513  
Option exercisable, contractual term 8 years 6 months  
Option, exercisable number 41,785  
Options Exercise Price 104.40 [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options, exercise price $ 104.40  
Option, outstanding number 11,383  
Option exercisable, contractual term 7 years 4 months 24 days  
Option, exercisable number 6,230