Note 5 - Segment Reporting (Detail) - Base Revenue and Fuel Surcharge Revenue by Segments (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Base revenue
Base Revenue	$ 100,324	$ 102,643	$ 301,667	$ 310,769
Fuel surcharge revenue
Fuel Surcharge Revenue	24,092	27,494	75,990	82,438
Total revenue	124,416	130,137	377,657	393,207
Trucking [Member]
Base revenue
Base Revenue	71,951	77,790	219,733	245,974
Fuel surcharge revenue
Fuel Surcharge Revenue	20,204	21,399	62,198	66,541
SCS [Member]
Base revenue
Base Revenue	29,339	21,144	84,049	56,629
Fuel surcharge revenue
Fuel Surcharge Revenue	4,546	4,295	13,679	10,992
Intermodal [Member]
Base revenue
Base Revenue	5,170	6,825	15,158	18,466
Fuel surcharge revenue
Fuel Surcharge Revenue	1,361	2,330	4,478	6,187
Intersegment Elimination [Member]
Base revenue
Base Revenue	(6,136)	(3,116)	(17,273)	(10,300)
Fuel surcharge revenue
Fuel Surcharge Revenue	$ (2,019)	$ (530)	$ (4,365)	$ (1,282)

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- Definition

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

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

+ References

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- Definition

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.

+ References

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