Quarterly report pursuant to Section 13 or 15(d)

Business Segments and Customer Information (Details)

v3.8.0.1
Business Segments and Customer Information (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2018
USD ($)
segment
Mar. 31, 2017
USD ($)
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]    
Number of reportable operating segments | segment 3  
Segment Reporting Information [Line Items]    
Revenues $ 176,897 $ 197,294
Operating income 11,593 14,196
Operating Segments | Supply Chain Management Group    
Segment Reporting Information [Line Items]    
Revenues 55,864 56,085
Operating income 7,596 8,483
Operating Segments | Aviation    
Segment Reporting Information [Line Items]    
Revenues 32,750 32,354
Operating income 2,261 2,336
Operating Segments | Federal Services Group    
Segment Reporting Information [Line Items]    
Revenues 88,283 108,855
Operating income 2,478 3,918
Corporate/unallocated expenses    
Segment Reporting Information [Line Items]    
Operating income $ (742) $ (541)