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ORGANIZATION AND DESCRIPTION OF THE BUSINESS AND FINANCIAL STATEMENT PRESENTATION (Organization) (Details) - segment |  | 3 Months Ended
--- | --- | ---
Nov. 03, 2013 | Mar. 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 |  | 68.00%
Wage rate reduction under collective bargaining agreement upon implementation date (as a percent) | 7.00% |
Wage rate increase for next three years of collective bargaining agreement (as a percent) | 2.00% |
Wage rate increase in fifth year of collective bargaining agreement (as a percent) | 2.50% |
Reduction in compensated vacation under collective bargaining agreement | 5 days |
Approximate initial reduction in combined total contractual wage and benefit rate under collective bargaining agreement (as a percent) | 4.00% |
Estimated increase in compounded annual contractual wage and benefit contribution rates in second through fifth years (as a percent) |  | 2.50%
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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