Note 4 - Long-term Debt - Oustanding Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Long-term debt, gross	$ 280,122	$ 480,472
Capital lease obligations, maturing at various dates through April 2024	21,244	27,761
Long-term debt and Captial lease obligations including current maturities	400,427	612,804
Less: Unamortized discount and debt issuance costs	(1,413)	(7,266)
Less: Current maturities of long-term debt	(120,305)	(132,332)
Long-term debt and capital lease obligations	278,709	473,206
Mortage Note Payable at 5.25% [Member]
Long-term debt, gross	19,161	20,033
Term Loan [Member]
Long-term debt, gross		193,177
Line of Credit [Member]
Long-term debt, gross		29,333
Term Loan at 4.3% [Member]
Long-term debt, gross	197,500
Revenue Equipment Loan [Member]
Long-term debt, gross	151,773	310,850
Notes Payable, Other Payables [Member]
Long-term debt, gross		25,516
Other Debt [Member]
Long-term debt, gross	$ 10,749	$ 6,134

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.

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