Note 7 - Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Net operating losses	$ 64,418	$ 75,303
Fixed asset basis difference	4,566	4,555
Contributions carryover	38	32
Deferred compensation	1,502	1,289
Accrued liabilities and others	333	303
Total deferred tax assets	70,857	81,482
Valuation allowance for deferred tax assets	(70,857)	(81,482)
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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