Commitments and Contingencies	12 Months Ended
Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and ContingenciesWe are a party to ordinary, routine litigation and administrative proceedings incidental to our business. In the opinion of management, our potential exposure under pending legal proceedings is adequately provided for in the accompanying consolidated financial statements. The total estimated purchase commitments for tractors, net of tractor sale commitments, and trailer equipment, at December 31, 2018, was $89.0 million.

The entire disclosure for commitments and contingencies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-URI http://asc.fasb.org/topic&trid=2127136

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-URI http://asc.fasb.org/topic&trid=2144648

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