Note 11 - Operating Revenue and Operating Income by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Truckload [Member] \| Revenue, Net of Fuel Surcharge [Member]
Operating revenue	$ 85,103	$ 88,822	$ 168,045	$ 175,633
Truckload [Member] \| Fuel Surcharge Revenue [Member]
Operating revenue	8,933	13,929	16,045	28,519
Truckload [Member]
Operating revenue	94,036	102,751	184,090	204,152
Operating Income	6,951	9,808	13,891	19,410
Dedicated [Member] \| Revenue, Net of Fuel Surcharge [Member]
Operating revenue	36,654	22,601	72,164	42,464
Dedicated [Member] \| Fuel Surcharge Revenue [Member]
Operating revenue	2,621	2,803	4,208	5,394
Dedicated [Member]
Operating revenue	39,275	25,404	76,372	47,858
Operating Income	5,134	2,563	9,458	4,567
Intermodal [Member] \| Revenue, Net of Fuel Surcharge [Member]
Operating revenue	16,118	16,101	31,972	33,120
Intermodal [Member] \| Fuel Surcharge Revenue [Member]
Operating revenue	1,664	2,945	3,011	6,318
Intermodal [Member]
Operating revenue	17,782	19,046	34,983	39,438
Operating Income	1,822	969	3,751	2,220
Brokerage [Member]
Operating revenue	14,997	16,387	32,574	33,427
Operating Income	869	821	1,801	1,563
Facility [Member]
Gain on disposition of facility				3,712
Operating revenue	166,090	163,588	328,019	324,875
Operating Income	14,776	14,161	28,901	31,472
Total operating income before gain on disposition of facility	$ 14,776	$ 14,161	$ 28,901	$ 27,760

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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