Note 4 - Long-term Debt - Oustanding Debt (Details) (Parentheticals) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Mortage Note Payable at 5.25% [Member]
Interest rate	5.25%	6.99%
Maturity date	Sep. 30, 2031	Sep. 30, 2031
Collateral	$ 23.9	$ 24.7
Term Loan [Member]
Interest rate		12.20%
Maturity date		May 31, 2020
Line of Credit [Member]
Maturity date		May 31, 2020
Term Loan at 4.3% [Member]
Interest rate	4.30%
Maturity date	Jun. 30, 2023
Revenue Equipment Loan [Member]
Maturity date	Oct. 31, 2023	Oct. 31, 2023
Weighted average interest rate	4.70%	4.70%
Collateral	$ 164.7	$ 315.7
Notes Payable, Other Payables [Member]
Interest rate		13.00%
Maturity date		Nov. 30, 2020
Capital Lease Obligations [Member]
Maturity date	Apr. 30, 2024	Apr. 30, 2024

Amount of assets pledged to secure a debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Weighted average interest rate of debt outstanding.

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