Note 7 - Supplemental Information Relating to Oil and Gas Producing Activities (Unaudited) - Changes in the Standardized Measure of Discounted Future Net Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Balance, beginning of year	$ 34,634	$ 6,776
Extensions, discoveries and other additions	353	171
Revision of quantity estimates	(36)	15,515
Sales of crude oil and natural gas, net of production costs	(3,227)	(11,310)
Net change in income taxes	485	(384)
Net changes in prices and production costs	(50,232)	17,370
Accretion of discount	3,463	678
Other	10,819	5,818
Balance, end of year	$ (3,741)	$ 34,634