Note 8 - Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Net operating losses	$ 69,537	$ 64,418
Fixed asset basis difference	4,599	4,566
Contributions carryover	48	38
Deferred compensation	695	497
Accrued liabilities and other	358	333
Total deferred tax assets	75,237	69,852
Valuation allowance for deferred tax assets	(75,237)	(69,852)
Net deferred tax asset	$ 0	$ 0

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible charitable contribution carryforwards.

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