Property, Equipment, and Depreciation (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Property, Plant and Equipment [Line Items]
Amortization Period of Tires			2 years
Change in estimate financial impact, per share, net of tax	$ 0.01		$ 0.02
Change in estimate financial impact, net of tax	1,900,000		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	$ 500,000	$ 300,000