Acquisitions - Consideration Transferred (Details) - USD ($)
3 Months Ended 9 Months Ended
Jun. 01, 2015
Mar. 31, 2016
Sep. 30, 2016
Sep. 30, 2015
Business Acquisition [Line Items]        
Contingent consideration, fair value     $ (31,025) $ 0
Working capital adjustment     $ 1,176,417  
Command Transportation, LLC        
Business Acquisition [Line Items]        
Cash $ 394,279,778      
Echo common stock, fair value 14,746,000      
Contingent consideration, fair value (1,176,417) $ (1,200,000)    
Working capital adjustment (142,969)      
Total consideration transferred $ 407,706,392