| 
           Net Income (Loss) Per Share (Details 1) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
| 
           Jun. 30, 2013 
         | 
        
           Jun. 30, 2012 
         | 
        
           Jun. 30, 2013 
         | 
        
           Jun. 30, 2012 
         | 
      |
| Calculation of the weighted average number of common shares outstanding | ||||
| Weighted-average anti-dilutive common shares | 4,636 | 18,392 | 1,198 | 8,949 | 
| 
           Stock Options [Member] 
         | 
        ||||
| Calculation of the weighted average number of common shares outstanding | ||||
| Weighted-average anti-dilutive common shares | 3,302 | 6,952 | 1,175 | 4,157 | 
| 
           Warrant [Member] 
         | 
        ||||
| Calculation of the weighted average number of common shares outstanding | ||||
| Weighted-average anti-dilutive common shares | 1,334 | 11,440 | 23 | 4,792 |