v2.4.0.8
Schedule of Stock-Based Compensation Expense Included in Statements of Income (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
Employee Service Share-based Compensation, Allocation of Recognized Period Costs              
Stock-based compensation expense, before tax $ 5,730 $ 3,998 $ 16,292 $ 11,976 $ 15,634 $ 13,107 $ 9,974
Income tax benefit (2,235) (1,559) (6,354) (4,671) (6,097) (5,059) (3,920)
Total stock-based compensation expense, net of tax 3,495 2,439 9,938 7,305 9,537 8,048 6,054
Cost of goods sold
             
Employee Service Share-based Compensation, Allocation of Recognized Period Costs              
Stock-based compensation expense, before tax 98 99 294 298 376 327 278
Facility and warehouse expenses
             
Employee Service Share-based Compensation, Allocation of Recognized Period Costs              
Stock-based compensation expense, before tax 687 648 2,058 1,951 2,465 2,391 2,069
Selling, general and administrative expenses
             
Employee Service Share-based Compensation, Allocation of Recognized Period Costs              
Stock-based compensation expense, before tax $ 4,945 $ 3,251 $ 13,940 $ 9,727 $ 12,793 $ 10,389 $ 7,627