Note 4 - Fair Value Measurements - Assets and Liabilities Measured On Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Commodity price derivatives – current	$ 435	$ 17
Derivatives	10,700	16,702
Derivatives	1,094	691
Commodity Contract [Member]
Total liabilities	11,359
Commodity Contract [Member] | Fair Value, Recurring [Member]
Commodity price derivatives – current	435
Commodity price derivatives		17
Derivatives	10,700	16,702
Derivatives	1,094	691
Total liabilities	11,794	17,393
Total recurring fair value measurements	(11,359)	(17,376)
Commodity Contract [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Commodity price derivatives – current	0
Commodity price derivatives		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 – current	435
Commodity price derivatives		17
Derivatives	10,700	16,702
Derivatives	1,094	691
Total liabilities	11,794	17,393
Total recurring fair value measurements	(11,359)	(17,376)
Commodity Contract [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Commodity price derivatives – current	0
Commodity price derivatives		0
Derivatives	0	0
Derivatives	0	0
Total liabilities	0	0
Total recurring fair value measurements	$ 0	$ 0