v2.4.0.6
Share-Based Payments (Share Options) (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2011
years
Dec. 31, 2010
Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]      
Balance at beginning of year (in shares) 93,964    
Granted (in shares) 0 0 0
Forfeited (in shares) (9,576)    
Expired (in shares) (7,350)    
Exercised (in shares) (12,126)    
Balance at end of year (in shares) 64,912 93,964  
Total Exercisable Shares 64,912    
Weighted Average Exercise Price at beginning of year $ 21.26    
Weighted Average Exercise Price, Granted $ 0.00    
Weighted Average Exercise Price, Forfeited $ 23.96    
Weighted Average Exercise Price, Expired $ 17.25    
Weighted Average Exercise Price, Exercised $ 13.50    
Weighted Average Exercise Price at end of year $ 22.76 $ 21.26  
Exercisable, Weighted Average Exercise Price $ 22.76    
Weighted Average Remaining Contractual Term 1.4    
Aggregate Intrinsic Value $ 52    
Exercisable, Weighted Average Remaining Contractual Term 1.4    
Exercisable, Aggregate Intrinsic Value 52    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value 65 154 123
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Number of Option Shares 64,912    
Weighted Average Remaining Contractual Life 1.4    
Weighted Average Exercise Price of Option Shares $ 22.76    
Number of Exercisable Option Shares 64,912    
Weighted Average Exercise Price of Exercisable Option Shares $ 22.76    
Stock-based compensation expense $ 1,635 $ 1,424 $ 1,038
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 9.26 To 12.34 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 9.26    
Range of Exercise Prices, Upper Limit $ 12.34    
Number of Option Shares 516    
Weighted Average Remaining Contractual Life 0.3    
Weighted Average Exercise Price of Option Shares $ 12.21    
Number of Exercisable Option Shares 516    
Weighted Average Exercise Price of Exercisable Option Shares $ 12.21    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 12.35 To 15.43 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 12.35    
Range of Exercise Prices, Upper Limit $ 15.43    
Number of Option Shares 6,395    
Weighted Average Remaining Contractual Life 1.8    
Weighted Average Exercise Price of Option Shares $ 14.04    
Number of Exercisable Option Shares 6,395    
Weighted Average Exercise Price of Exercisable Option Shares $ 14.04    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 15.44 To 18.51 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 15.44    
Range of Exercise Prices, Upper Limit $ 18.51    
Number of Option Shares 5,184    
Weighted Average Remaining Contractual Life 1.5    
Weighted Average Exercise Price of Option Shares $ 17.36    
Number of Exercisable Option Shares 5,184    
Weighted Average Exercise Price of Exercisable Option Shares $ 17.36    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 18.52 To 21.60 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 18.52    
Range of Exercise Prices, Upper Limit $ 21.60    
Number of Option Shares 7,266    
Weighted Average Remaining Contractual Life 2.3    
Weighted Average Exercise Price of Option Shares $ 18.61    
Number of Exercisable Option Shares 7,266    
Weighted Average Exercise Price of Exercisable Option Shares $ 18.61    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 21.61 To 24.68 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 21.61    
Range of Exercise Prices, Upper Limit $ 24.68    
Number of Option Shares 12,000    
Weighted Average Remaining Contractual Life 0.8    
Weighted Average Exercise Price of Option Shares $ 22.61    
Number of Exercisable Option Shares 12,000    
Weighted Average Exercise Price of Exercisable Option Shares $ 22.61    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 24.69 To 27.77 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 24.69    
Range of Exercise Prices, Upper Limit $ 27.77    
Number of Option Shares 29,500    
Weighted Average Remaining Contractual Life 0.8    
Weighted Average Exercise Price of Option Shares $ 25.75    
Number of Exercisable Option Shares 29,500    
Weighted Average Exercise Price of Exercisable Option Shares $ 25.75    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range From 27.78 To 30.86 [Member]
     
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract]      
Range of Exercise Prices, Lower Limit $ 27.78    
Range of Exercise Prices, Upper Limit $ 30.86    
Number of Option Shares 4,051    
Weighted Average Remaining Contractual Life 5.1    
Weighted Average Exercise Price of Option Shares $ 30.86    
Number of Exercisable Option Shares 4,051    
Weighted Average Exercise Price of Exercisable Option Shares $ 30.86    
Stock Option [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share Based Compensation Arrangement By Share Based Payment Award, Exercisable Period 5 years    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 3 years    
Share Based Compensation Arrangement By Share Based Payment Award, Maximum Term 10 years