Note 8 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	2021			2020
Expected amount	$	(783	)	$	(1,865	)
State income taxes, net of federal benefit		(767	)		(644	)
Percentage depletion		(1,725	)		(2,154	)
Valuation allowance		3,376			1,275
Stock-based compensation		380			67
PPP loan forgiveness		(2,100	)		—
Return to provision adjustments		1,610			(60	)
Other		35			723
	$	26		$	(2,658	)

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	2021			2020
Deferred tax assets:
Net operating loss	$	32,659		$	24,081
Valuation allowance		(4,651	)		(1,275	)
Capital loss carryforward		—			525
Stock-based compensation		—			179
Other		—			234
Total deferred tax assets		28,008			23,744
Deferred tax liabilities:
Coal properties		(30,368	)		(26,171	)
Investment in partnerships		(484	)		(397	)
Other		(6	)		—
Total deferred tax liabilities		(30,858	)		(26,568	)
Net deferred tax liability	$	(2,850	)	$	(2,824	)