v3.23.1

Note 17 - Income Taxes (Details Textual) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Deferred Tax Assets, Valuation Allowance | $ 64,341 | $ 51,437 |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | 12,904 | 31,150 |
Deferred Tax Assets, Net of Valuation Allowance, Total | 947 | 284 |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total | 0 | 0 |
Research Tax Credit Carryforward [Member] |  |  |
Tax Credit Carryforward, Amount | 276 |  | $ 0
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] |  |  |
Operating Loss Carryforwards | $ 191,313 | $ 163,395 |

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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319 + Details
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