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Property, Equipment, and Depreciation (Details) (USD $) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Property, Plant and Equipment [Line Items] |  |  |  |
Amortization Period of Tires |  |  | 2 years |
Change in estimate financial impact, per share, net of tax |  |  | $ 0.02 |
Change in estimate financial impact, net of tax |  |  | 3,300,000 |
Tractors |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Property, Plant, and Equipment, Salvage Value | 15,000 |  | 15,000 |
Trailers |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Property, Plant, and Equipment, Salvage Value | 4,000 |  | 4,000 |
Communications and Utilities Expense |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Depreciation | $ 300,000 | $ 200,000 | $ 800,000 | $ 500,000

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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
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