Note 7 - Income Taxes - Difference Between Expected Amount and Actual Amount, Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Expected amount	$ 10,344	$ 4,171
State income taxes, net of federal benefit	1,246	391
Percentage depletion	(3,348)	(2,081)
Change in valuation allowance	(3,681)	(970)
Stock-based compensation	(844)	0
Return to provision adjustments	159	153
Other	589	92
Total income tax expense	$ 4,465	$ 1,756

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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