Note 7 - Debt (Details) - Current and Long-term Debt (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Note 7 - Debt (Details) - Current and Long-term Debt [Line Items]
Borrowings under Credit Facility	$ 0us-gaap_LinesOfCreditCurrent	$ 0us-gaap_LinesOfCreditCurrent
Borrowings under Credit Facility		7,010us-gaap_LongTermLineOfCredit
Notes payable, current	27,824us-gaap_LongTermDebtCurrent	44,070us-gaap_LongTermDebtCurrent
Notes payable, long-term	159,531us-gaap_LongTermDebtNoncurrent	169,491us-gaap_LongTermDebtNoncurrent
Principal portion of capital lease obligations, secured by related revenue equipment	1,606us-gaap_CapitalLeaseObligationsCurrent	8,732us-gaap_CapitalLeaseObligationsCurrent
Principal portion of capital lease obligations, secured by related revenue equipment	13,372	13,186
Total debt and capital lease obligations	29,430	52,802
Total debt and capital lease obligations	172,903	182,677
Revenue Equipment Installment Notes [Member]
Note 7 - Debt (Details) - Current and Long-term Debt [Line Items]
Notes payable, current	27,550	43,745
Notes payable, long-term	155,832	158,596
Real Estate Note [Member]
Note 7 - Debt (Details) - Current and Long-term Debt [Line Items]
Notes payable, current	166	217
Notes payable, long-term	3,608	3,693
Other Note Payable [Member]
Note 7 - Debt (Details) - Current and Long-term Debt [Line Items]
Notes payable, current	108	108
Notes payable, long-term	$ 91	$ 192

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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