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Significant Accounting Policies Property, Equipment and Depreciation (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Property, Plant and Equipment |  |  |
Amortization Period of Tires | 2 years |  |
Accumulated Depreciation, Depletion and Amortization, Property, Plant and Equipment, Period Increase (Decrease) |  |  | $ 3,300,000
change in estimate financial impact, per share, net of tax |  |  | $ 0.02
Communications and Utilities Expense [Member] |  |  |
Property, Plant and Equipment |  |  |
Depreciation | $ 900,000 | $ 1,100,000 |
Tractors [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant, and Equipment, Salvage Value | 15,000 |  |
Trailers [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant, and Equipment, Salvage Value | $ 4,000 |  |
Minimum [Member] | Land Improvements and Buildings [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 5 years |  |
Minimum [Member] | Leasehold Improvements [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 5 years |  |
Minimum [Member] | Furniture and Fixtures [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Minimum [Member] | Shop and Service Equipment [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Minimum [Member] | Revenue Equipment [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 5 years |  |
Maximum [Member] | Land Improvements and Buildings [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 30 years |  |
Maximum [Member] | Leasehold Improvements [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 25 years |  |
Maximum [Member] | Furniture and Fixtures [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 5 years |  |
Maximum [Member] | Shop and Service Equipment [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 10 years |  |
Maximum [Member] | Revenue Equipment [Member] |  |  |
Property, Plant and Equipment |  |  |
Property, Plant and Equipment, Useful Life | 7 years |  |

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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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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