| 
           Industry, Segment and Geographic Information (Details 2) (USD $) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 
           Dec. 31, 2012 
         | 
        
           Sep. 30, 2012 
         | 
        
           Jun. 30, 2012 
         | 
        
           Mar. 31, 2012 
         | 
        
           Dec. 31, 2011 
         | 
        
           Sep. 30, 2011 
         | 
        
           Jun. 30, 2011 
         | 
        
           Mar. 31, 2011 
         | 
        
           Dec. 31, 2012
 
          item 
         | 
        
           Dec. 31, 2011 
         | 
        
           Dec. 31, 2010 
         | 
      |
| Industry, Segment and Geographic Information | |||||||||||
| Number of reportable operating segments | 2 | ||||||||||
| Segment reporting information | |||||||||||
| Revenue | $ 85,447 | $ 75,534 | $ 69,169 | $ 66,907 | $ 74,218 | $ 63,741 | $ 60,661 | $ 51,549 | $ 297,057 | $ 250,169 | $ 206,730 | 
| Gross Profit | 7,037 | 5,698 | 5,590 | 5,567 | 7,058 | 5,757 | 5,601 | 4,825 | 23,892 | 23,241 | 20,010 | 
| Direct Costs | 8,079 | 7,773 | 6,866 | ||||||||
| Segment Income Before Taxes | 8,515 | 8,618 | 6,803 | ||||||||
| General and administrative | 7,298 | 6,850 | 6,341 | ||||||||
| Interest income | 557 | 368 | 405 | ||||||||
| Foreign currency translation gains | 17 | 1 | 2 | ||||||||
| Income before provision for income taxes | 9,089 | 8,987 | 7,210 | ||||||||
| Total assets | 91,445 | 74,861 | 91,445 | 74,861 | 68,683 | ||||||
| 
           Segment Total 
         | 
        |||||||||||
| Segment reporting information | |||||||||||
| Segment Income Before Taxes | 15,813 | 15,468 | 13,144 | ||||||||
| Total assets | 74,956 | 57,195 | 74,956 | 57,195 | |||||||
| 
           TechXtend 
         | 
        |||||||||||
| Segment reporting information | |||||||||||
| Revenue | 79,715 | 57,449 | 57,579 | ||||||||
| Gross Profit | 8,074 | 6,437 | 6,307 | ||||||||
| Direct Costs | 3,567 | 3,058 | 2,932 | ||||||||
| Segment Income Before Taxes | 4,507 | 3,379 | 3,375 | ||||||||
| Total assets | 44,698 | 27,881 | 44,698 | 27,881 | |||||||
| 
           Lifeboat Distribution 
         | 
        |||||||||||
| Segment reporting information | |||||||||||
| Revenue | 217,342 | 192,720 | 149,151 | ||||||||
| Gross Profit | 15,818 | 16,804 | 13,703 | ||||||||
| Direct Costs | 4,512 | 4,715 | 3,934 | ||||||||
| Segment Income Before Taxes | 11,306 | 12,089 | 9,769 | ||||||||
| Total assets | 30,258 | 29,314 | 30,258 | 29,314 | |||||||
| 
           Corporate assets 
         | 
        |||||||||||
| Segment reporting information | |||||||||||
| Total assets | $ 16,489 | $ 17,666 | $ 16,489 | $ 17,666 | |||||||