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Profit Sharing Plan and Retirement Plan | 12 Months Ended
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Dec. 31, 2012
Profit Sharing Plan and Retirement Plan [Abstract] |
Compensation and Employee Benefit Plans [Text Block] | Profit Sharing Plan and Retirement Plan The Company has a retirement savings plan (the "Plan") for substantially all employees who have completed one year of service and are 19 years of age or older. Employees may make 401(k) contributions subject to Internal Revenue Code limitations. The Plan provides for a discretionary profit sharing contribution to non-driver employees and a matching contribution of a discretionary percentage to driver employees. Company profit sharing contributions totaled approximately $0.7 million, $0.8 million, and $0.7 million, for the years ended December 31, 2012, 2011 and 2010, respectively.

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