v2.4.0.8
Schedule of Pre-Tax Stock-Based Compensation Expense (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2013
Sep. 30, 2012
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award              
Stock-based compensation expense $ 5,730 $ 3,998 $ 16,292 $ 11,976 $ 15,634 $ 13,107 $ 9,974
RSUs
             
Share-based Compensation Arrangement by Share-based Payment Award              
Stock-based compensation expense 4,559 2,048 12,674 6,131 8,411 3,666  
Stock Options
             
Share-based Compensation Arrangement by Share-based Payment Award              
Stock-based compensation expense 1,124 1,720 3,457 5,162 6,310 8,129 8,771
Restricted Stock
             
Share-based Compensation Arrangement by Share-based Payment Award              
Stock-based compensation expense 47 230 161 683 913 913 913
Stock Issued To Non-Employee Directors
             
Share-based Compensation Arrangement by Share-based Payment Award              
Stock-based compensation expense           $ 399 $ 290