Note 12 - Business Segments (Details Textual)	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Intermodal [Member]
Depreciation, Depletion and Amortization	$ 1,400,000	$ 1,600,000	$ 2,900,000	$ 2,900,000
Truckload [Member]
Depreciation, Depletion and Amortization	13,500,000	13,200,000	26,700,000	26,500,000
Dedicated [Member]
Depreciation, Depletion and Amortization	3,200,000	1,800,000	6,000,000	3,300,000
Brokerage [Member]
Depreciation, Depletion and Amortization	$ 289,000	$ 240,000	$ 559,000	$ 464,000
Number of Operating Segments			6
Number of Reportable Segments			4	2