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ORGANIZATION AND DESCRIPTION OF THE BUSINESS AND FINANCIAL STATEMENT PRESENTATION (Organization) (Details) - segment | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2018
Organization and description of business |  |
Number of reportable operating segments |  | 3
Asset-Based |  |
Organization and description of business |  |
Percentage of the Company's revenues, before other revenues and intercompany eliminations, represented by the Asset-Based segment |  | 69.00%
Vacation accrual period | 5 days |
Asset-Based | Unionized employees concentration risk | Number of employees |  |
Organization and description of business |  |
Percentage of Asset-Based segment employees covered under collective bargaining agreement with the IBT |  | 82.00%

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