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Note 13 - Fair Value Measurements (Details Textual) bbl in Millions, $ in Millions | 9 Months Ended
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Sep. 30, 2021 USD ($) $ / gal bbl
Interest Rate Swap [Member] |
Derivative, Number of Instruments Held, Total | 2
Interest Rate Swap, One [Member] |
Derivative, Notional Amount | $ | $ 52.7
Interest Rate Swap, Two [Member] |
Derivative, Notional Amount | $ | $ 40.4
Fuel Hedge [Member] |
Derivative, Nonmonetary Notional Amount, Volume (Barrel of Oil) | bbl | 0.2
Underlying, Derivative Volume (in USD per Gallon) | $ / gal | 1.79
Fuel Hedge [Member] | Maximum [Member] |
Underlying, Derivative Volume (in USD per Gallon) | $ / gal | 2.00

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