Note 11 - Operating Revenue and Operating Income by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Truckload [Member] \| Revenue, Net of Fuel Surcharge [Member]
Operating revenue	$ 82,942	$ 86,811
Truckload [Member] \| Fuel Surcharge Revenue [Member]
Operating revenue	7,112	14,590
Truckload [Member]
Operating revenue	90,054	101,401
Operating Income	6,940	9,602
Dedicated [Member] \| Revenue, Net of Fuel Surcharge [Member]
Operating revenue	35,510	19,863
Dedicated [Member] \| Fuel Surcharge Revenue [Member]
Operating revenue	1,587	2,591
Dedicated [Member]
Operating revenue	37,097	22,454
Operating Income	4,324	2,004
Intermodal [Member] \| Revenue, Net of Fuel Surcharge [Member]
Operating revenue	15,854	17,019
Intermodal [Member] \| Fuel Surcharge Revenue [Member]
Operating revenue	1,347	3,373
Intermodal [Member]
Operating revenue	17,201	20,392
Operating Income	1,929	1,251
Brokerage [Member]
Operating revenue	17,577	17,040
Operating Income	$ 932	742
Facility [Member]
Gain on disposition of facility		3,712
Operating revenue	$ 161,929	161,287
Operating Income	14,125	17,311
Total operating income before gain on disposition of facility	$ 14,125	$ 13,599

Represents the operating income or loss before the gain or loss on the disposition of the facility.

No definition available.

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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