Note 7 - Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Net operating losses	$ 75,303	$ 70,202
Fixed asset basis difference	4,555	4,547
Contributions carryover	32	30
Deferred compensation	1,289	1,098
Accrued liabilities and others	303	271
Total deferred tax assets	81,482	76,148
Valuation allowance for deferred tax assets	(81,482)	(76,148)
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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