Note 10 - Long-term Debt - Outstanding Debt (Details) (Parentheticals) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Term Loan [Member]
Interest rate		12.20%
Maturity date		May 31, 2020
Line of Credit [Member]
Maturity date		Mar. 31, 2020
Term Loan at 4.8% [Member]
Interest rate		4.80%
Maturity date		Jun. 30, 2023
Revenue Equipment Loan [Member]
Maturity date	Dec. 31, 2025	Dec. 31, 2025
Weighted average interest rate	5.00%	4.70%
Collateral	$ 197.1	$ 315.7
Notes Payable, Other Payables [Member]
Interest rate		13.00%
Maturity date		Nov. 30, 2020
Mortgage Note Payable [Member]
Collateral	$ 241.0	$ 247.0
Mortgage Note Payable [Member] \| Minimum [Member]
Interest rate	5.25%	5.25%
Mortgage Note Payable [Member] \| Maximum [Member]
Interest rate	6.99%	6.99%
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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Weighted average interest rate of debt outstanding.

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