Note 4 - Fair Value Measurements - Assets and Liabilities Measured On Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Derivatives	$ 16,702	$ 13,591
Derivatives	691	4,075
Commodity Contract [Member]
Total liabilities	17,376
Commodity Contract [Member] \| Fair Value, Recurring [Member]
Commodity price derivatives	17	2,199
Derivatives	16,702	13,591
Derivatives	691	4,075
Total liabilities	17,393	17,666
Total recurring fair value measurements	(17,376)	(15,467)
Commodity Contract [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Commodity price derivatives	0	0
Derivatives	0	0
Derivatives	0	0
Total liabilities	0	0
Total recurring fair value measurements	0	0
Commodity Contract [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Commodity price derivatives	17	2,199
Derivatives	16,702	13,591
Derivatives	691	4,075
Total liabilities	17,393	17,666
Total recurring fair value measurements	(17,376)	(15,467)
Commodity Contract [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Commodity price derivatives	0	0
Derivatives	0	0
Derivatives	0	0
Total liabilities	0	0
Total recurring fair value measurements	$ 0	$ 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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