PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, Gross	$ 452,418		$ 455,815
Accumulated depreciation	(149,383)		(137,068)
Property and equipment, Net	303,035		318,747
Depreciation	14,873	$ 15,344
Revenue equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, Gross	394,174		398,394
Buildings and improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, Gross	42,970		43,000
Furniture and fixtures, office and computer equipment and vehicles
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, Gross	$ 15,274		$ 14,421