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.

+ Details

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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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Note 15 - Operating Revenue and Operating Income by Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating revenue	$ 172,661	$ 170,464	$ 166,090	$ 161,929	$ 168,773	$ 171,346	$ 163,588	$ 161,287	$ 671,144	$ 664,994	$ 672,929
Operating Income	$ 14,533	$ 14,869	$ 14,776	$ 14,125	$ 15,237	$ 14,354	$ 14,161	$ 17,311	58,303	61,063	51,006
Facility [Member]
Total operating income before gain on disposition of facilities									58,303	56,959	51,006
Gain on disposition of facilities										4,104
Truckload [Member]
Operating revenue									375,851	398,361	448,273
Operating Income									27,438	35,517	39,483
Dedicated [Member]
Operating revenue									157,370	118,272	70,352
Operating Income									19,550	12,818	7,136
Intermodal [Member]
Operating revenue									71,490	76,958	97,092
Operating Income									7,131	4,832	1,735
Brokerage [Member]
Operating revenue									66,433	71,403	57,212
Operating Income									4,184	3,792	2,652
Revenue, Net of Fuel Surcharge [Member] \| Truckload [Member]
Operating revenue									339,967	348,101	358,458
Revenue, Net of Fuel Surcharge [Member] \| Dedicated [Member]
Operating revenue									147,007	107,264	56,609
Revenue, Net of Fuel Surcharge [Member] \| Intermodal [Member]
Operating revenue									64,508	65,877	75,447
Fuel Surcharge Revenue [Member] \| Truckload [Member]
Operating revenue									35,884	50,260	89,815
Fuel Surcharge Revenue [Member] \| Dedicated [Member]
Operating revenue									10,363	11,008	13,743
Fuel Surcharge Revenue [Member] \| Intermodal [Member]
Operating revenue									$ 6,982	$ 11,081	$ 21,645