| 
           Stock-Based Compensation (Summary Of Stock-Based Compensation Expense) (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| 
           Sep. 30, 2012 
         | 
        
           Sep. 30, 2011 
         | 
        
           Sep. 30, 2012 
         | 
        
           Sep. 30, 2011 
         | 
      |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Stock-based compensation expense | $ 1,404 | $ 2,051 | $ 5,707 | $ 5,855 | 
| 
           Stock Options [Member] 
         | 
        ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Stock-based compensation expense | 607 | 906 | 2,384 | 2,633 | 
| 
           Restricted Stock Units [Member] 
         | 
        ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Stock-based compensation expense | $ 797 | $ 1,145 | $ 3,323 | $ 3,222 |