Quarterly report pursuant to Section 13 or 15(d)

Share-Based Payments - Employee Activity Performance Shares (Details)

v2.4.0.8
Share-Based Payments - Employee Activity Performance Shares (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense $ 1,536 $ 1,517 $ 3,094 $ 3,123
Key Employee Performance Share Based Plan [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Period of Share Price Performance Comparison to Peer Group     3 years  
Minimum percentage of peer group by which Company share price must outperform before incremental performance shares are issued     30.00%  
Percentage of Peer Group By Which Company Share Price Must Outperform Before Maximum Incremental Shares Are Issued     90.00%  
Expected Stock Price Volatility Rate     34.50% 40.80%
Weighted Average Risk Free Interest Rate     0.40% 0.40%
Outstanding and non-vested, beginning of period (in shares) 88   62  
Grants in Period 0   26  
Shares Vested in Period 0   0  
Outstanding and non-vested, end of period (in shares) 88   88  
Outstanding and non-vested, weighted-average grant date fair value, beginning of period $ 37   $ 36  
Grants in Period, Weighted Average Grant Date Fair Value $ 0   $ 40  
Vested in Period, Weighed-average grant date fair value $ 0   $ 0  
Outstanding and non-vested, weighted-average grant date fair value, end of period $ 37   $ 37  
Outstanding and non-vested, aggregate grant date fair value 3,278   3,278  
Share-based compensation expense 272 183 505 330
Tax benefit related to share-based expense 104 70 193 127
Unrecognized share-based compensation, net of estimated forfeitures $ 1,740 $ 1,541 $ 1,740 $ 1,541