Introduction and Description of Business (Details)	3 Months Ended
	Mar. 31, 2021 Vehicle Segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operational tractors in fleet	18,224
Number of company tractors	16,305
Number of independent contractor tractors	1,919
Number of trailers	59,797
Number of intermodal tractors	597
Number of intermodal containers	10,846
Number of reportable segments | Segment	3