Note 5 - Segment Reporting (Detail) - Base Revenue and Fuel Surcharge Revenue by Segments (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Base revenue
Trucking	$ 71,846	$ 85,309	$ 147,782	$ 168,184
Total base revenue	103,520	108,474	201,342	208,126
Fuel surcharge revenue
Total fuel surcharge revenue	26,049	30,553	51,900	54,943
Total revenue	129,569	139,027	253,242	263,069
Trucking [Member]
Base revenue
Trucking	71,846	85,309	147,782	168,184
Fuel surcharge revenue
Trucking	20,964	24,742	41,995	45,141
SCS [Member]
Base revenue
Base Revenue	32,392	21,550	54,710	35,485
Fuel surcharge revenue
Fuel Surcharge Revenue	5,108	4,170	9,133	6,696
Intermodal [Member]
Base revenue
Base Revenue	5,582	5,881	9,988	11,641
Fuel surcharge revenue
Fuel Surcharge Revenue	1,813	2,189	3,117	3,857
Intersegment Elimination [Member]
Base revenue
Base Revenue	(6,300)	(4,266)	(11,138)	(7,184)
Fuel surcharge revenue
Fuel Surcharge Revenue	$ (1,836)	$ (548)	$ (2,345)	$ (751)

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- Definition

Amount of base revenue attributed to the reportable segment, including intercompany base revenue.

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Amount of repayment received or receivable for expenses incurred on behalf of a client or customer attributed to the reportable segment, including intercompany revenue.

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Repayment received or receivable for expenses incurred on behalf of a client or customer from the transporting of freight.

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Revenue from transporting cargo and freight between locations by tractor/trailer/rail.

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Revenue from transporting cargo and freight between locations.

+ 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(d))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-AIR

-Paragraph 4

-IssueDate 2003-05-01

-Chapter 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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