Note 4 - Fair Value Measurements - Assets and Liabilities Measured On Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Derivatives	$ 11,071	$ 13,591
Derivatives	0	4,075
Fair Value, Recurring [Member]
Total recurring fair value measurements	6,190
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total recurring fair value measurements	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total recurring fair value measurements	6,190
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total recurring fair value measurements	0
Commodity Contract [Member]
Commodity price derivatives	(6,190)
Total liabilities	(6,190)
Commodity Contract [Member] \| Fair Value, Inputs, Level 3 [Member]
Commodity price derivatives		0
Commodity price derivatives		0
Derivatives		0
Total recurring fair value measurements		0
Derivatives		0
Total liabilities		0
Commodity Contract [Member] \| Fair Value, Recurring [Member]
Commodity price derivatives	17,261	2,199
Commodity price derivatives	11,071	17,666
Derivatives		13,591
Total recurring fair value measurements		(15,467)
Derivatives		4,075
Total liabilities	11,071	17,666
Commodity Contract [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Commodity price derivatives	0	0
Commodity price derivatives	0	0
Derivatives		0
Total recurring fair value measurements		0
Derivatives		0
Total liabilities	0	0
Commodity Contract [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Commodity price derivatives	17,261	2,199
Commodity price derivatives	11,071	17,666
Derivatives		13,591
Total recurring fair value measurements		(15,467)
Derivatives		4,075
Total liabilities	11,071	$ 17,666
Commodity Contract [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Commodity price derivatives	0
Commodity price derivatives	0
Total liabilities	$ 0

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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