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Acquisition - Additional Information (Detail)
$ in Thousands
3 Months Ended 9 Months Ended
Jul. 01, 2017
USD ($)
Tractor
Trailer
Sep. 30, 2017
USD ($)
Sep. 30, 2017
USD ($)
Hub Group Dedicated [Member]      
Business Acquisition [Line Items]      
Number of tractors in operating fleet | Tractor 1,000    
Number of trailers in operating fleet | Trailer 3,600    
Estenson Logistics, LLC [Member]      
Business Acquisition [Line Items]      
Business acquisition date     Jul. 01, 2017
Business acquisition, purchase price $ 284,691    
Contingent consideration related to an earn-out provision 6,000    
Business acquisition, final consideration 172,014    
Business acquisition, debt assumed 112,677    
Business acquisition, cash paid 165,945    
Amount of cash borrowed under new line of credit $ 55,000    
Business acquisition costs     $ 1,600
Amortization expense of intangible assets   $ 1,500 $ 1,500
Intangible assets, weighted average useful life     15 years