Note 12 - Business Segments - Operating Revenue and Operating Income by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue, Net of Fuel Surcharge [Member] \| Truckload [Member]
Truckload revenue, net of fuel surcharge revenue	$ 86,594	$ 89,515	$ 262,227	$ 266,633
Revenue, Net of Fuel Surcharge [Member] \| Dedicated [Member]
Truckload revenue, net of fuel surcharge revenue	31,477	15,756	73,941	38,329
Revenue, Net of Fuel Surcharge [Member] \| Intermodal [Member]
Truckload revenue, net of fuel surcharge revenue	17,158	19,229	50,278	57,989
Fuel Surcharge Revenue [Member] \| Truckload [Member]
Truckload revenue, net of fuel surcharge revenue	11,777	21,821	40,296	69,232
Fuel Surcharge Revenue [Member] \| Dedicated [Member]
Truckload revenue, net of fuel surcharge revenue	2,937	3,995	8,331	10,062
Fuel Surcharge Revenue [Member] \| Intermodal [Member]
Truckload revenue, net of fuel surcharge revenue	2,673	5,793	8,991	16,929
Truckload [Member]
Truckload revenue, net of fuel surcharge revenue	98,371	111,336	302,523	335,865
Truckload	8,204	10,455	27,614	27,043
Total operating income	8,204	10,455	27,614	27,043
Dedicated [Member]
Truckload revenue, net of fuel surcharge revenue	34,414	19,751	82,272	48,391
Truckload	3,929	2,046	8,496	4,801
Total operating income	3,929	2,046	8,496	4,801
Intermodal [Member]
Truckload revenue, net of fuel surcharge revenue	19,831	25,022	59,269	74,918
Truckload	1,152	(151)	3,372	815
Total operating income	1,152	(151)	3,372	815
Brokerage [Member]
Truckload revenue, net of fuel surcharge revenue	18,730	15,441	52,157	40,208
Truckload	1,069	692	2,632	1,955
Total operating income	$ 1,069	$ 692	2,632	$ 1,955
Facility [Member]
Gain on disposition of facility			3,712
Truckload revenue, net of fuel surcharge revenue	$ 171,346	$ 171,550	496,221	$ 499,382
Truckload	14,354	13,042	45,826	34,614
Total operating income before gain on disposition of facility	14,354	13,042	42,114	34,614
Total operating income	$ 14,354	$ 13,042	$ 45,826	$ 34,614

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=51824106&loc=d3e2443-110228

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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=26872669&loc=d3e20235-122688

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