Annual report pursuant to Section 13 and 15(d)

Stock Based Compensation - Options (Details)

v2.4.0.6
Stock Based Compensation - Options (Details) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock Options, Vesting Percentage, After Year One 50.00%      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]        
Options outstanding, beginning 89,106 145,950 314,250  
Stock Options, granted 0 0 0  
Options exercised (44,987) (51,081) (164,300)  
Stock Options, expired/forfeited (6,000) (5,763) (4,000)  
Options outstanding, ending 38,119 89,106 145,950  
Stock Options, exercisable 38,119 89,106 145,950  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]        
Weighted average exercise price, beginning $ 30.48 $ 27.69 $ 26.74 $ 25.39
Stock Options, granted, weighted average exercise price $ 0.00 $ 0.00 $ 0.00  
Stock Options, exercised, weighted average exercise price $ 25.61 $ 25.29 $ 24.11  
Stock Options, expired/forfeited, weighted average exercise price $ 25.61 $ 24.85 $ 28.23  
Weighted average exercise price, ending $ 30.48 $ 27.69 $ 26.74 $ 25.39
Stock Options, weighted average exercise price $ 30.48 $ 27.69 $ 26.74  
Aggregate intrinsic value of outstanding exercisable shares $ 0      
Aggregate intrinsic value of options exercised $ 100,000 $ 300,000 $ 1,000,000  
Options forfeited 0 0 3,350  
Stock Options [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock Options, Expiration in Years 10 years      
Employee Stock Option [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]        
Weighted average exercise price, beginning $ 30.48      
Weighted average exercise price, ending $ 30.48      
Exercise price, minimum $ 29.55      
Exercise price, maximum $ 33.09      
Weighted average remaining contractual term, options outstanding (years) 1 year 2 months 12 days