Note 13 - Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Unrecognized derivative losses	$ 4,074	$ 0
Stock-based compensation	3,589	3,124
Net operating loss carryforwards	51	9,725
Other	79	31
Less: Valuation allowance	0	0
Net deferred tax assets	7,793	12,880
Crude oil and natural gas properties, principally due to differences in basis and depreciation and the deduction of intangible drilling costs for tax purposes	(51,371)	(51,778)
Net deferred tax liabilities	$ (43,578)	$ (38,898)

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from derivative instruments.

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