Note 5 - Derivative Financial Instruments - Commodity Derivative Contracts (Details) - Not Designated as Hedging Instrument [Member]	3 Months Ended
	Mar. 31, 2022 $ / bbl bbl
Crude Oil Derivative Swap Q1 2022 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	1,039.8
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	71.96
Crude Oil Derivative Swap Q2 2022 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	456.4
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	75.15
Crude Oil Derivative Swap Q3 2022 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	487.4
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	70.14
Crude Oil Derivative Swap Q4 2022 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	1,983.6
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	72.25
Crude Oil Derivative Swap 2022 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	441.0
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	70.05
Crude Oil Derivative Swap Q1 2023 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	200.2
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	57.22
Crude Oil Derivative Swap Q2 2023 [Member]
Volume (MBbls) (Barrel of Oil) | bbl	641.2
Price per Bbl (in USD per Barrel of Oil) | $ / bbl	66.04