Note 8 - Income Taxes - Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Net operating losses	$ 82,076	$ 75,727
Fixed asset basis difference	4,839	4,738
Contributions carryover	43	29
Deferred compensation	332	157
Accrued liabilities and other	980	796
Total deferred tax assets	88,270	81,447
Valuation allowance for deferred tax assets	(88,270)	(81,447)
Net deferred tax asset	$ 0	$ 0

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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