| 
           Business Segments and Customer Information (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| 
           Sep. 30, 2014 
         | 
        
           Sep. 30, 2013 
         | 
        
           Sep. 30, 2014 
         | 
        
           Sep. 30, 2013 
         | 
      |
| Segment Reporting Information [Line Items] | ||||
| Number of reportable operating segments | 4 | |||
| Revenues | $ 101,749 | $ 111,069 | $ 329,120 | $ 349,288 | 
| Operating Income | 7,183 | 9,460 | 29,243 | 32,103 | 
| 
           Supply Chain Management Group [Member] 
         | 
        ||||
| Segment Reporting Information [Line Items] | ||||
| Revenues | 44,542 | 39,665 | 127,478 | 114,260 | 
| Operating Income | 6,195 | 7,306 | 21,713 | 20,435 | 
| 
           International Group [Member] 
         | 
        ||||
| Segment Reporting Information [Line Items] | ||||
| Revenues | 24,718 | 35,428 | 86,228 | 107,057 | 
| Operating Income | 291 | 2,285 | 3,439 | 5,451 | 
| 
           Federal Group [Member] 
         | 
        ||||
| Segment Reporting Information [Line Items] | ||||
| Revenues | 17,197 | 17,043 | 68,889 | 71,430 | 
| Operating Income | (396) | (2,303) | 820 | 1,338 | 
| 
           IT, Energy and Management Consulting Group [Member] 
         | 
        ||||
| Segment Reporting Information [Line Items] | ||||
| Revenues | 15,292 | 18,933 | 46,525 | 56,541 | 
| Operating Income | 1,866 | 2,475 | 5,151 | 6,206 | 
| 
           Corporate/unallocated [Member] 
         | 
        ||||
| Segment Reporting Information [Line Items] | ||||
| Operating Income | $ (773) | $ (303) | $ (1,880) | $ (1,327) |