v3.23.2

Note 19 - Income Taxes (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Income Tax Expense (Benefit), Total | $ 13 | $ 5
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation | 0 | 0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | 13,500 | 6,400
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total | $ 0 | 0
Open Tax Year | 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2016 2017 2018 2019 2020 2021 2022 |
Increase (Decrease) in Employee Related Liabilities, Total |  | $ 1,400
Subject to Expiration [Member] |  |
Operating Loss Carryforwards | $ 1,400 |
Research Tax Credit Carryforward [Member] | Subject to Expiration [Member] |  |
Tax Credit Carryforward, Amount | 26 |
Domestic Tax Authority [Member] |  |
Operating Loss Carryforwards | 346,400 |
Domestic Tax Authority [Member] | Research Tax Credit Carryforward [Member] |  |
Tax Credit Carryforward, Amount | 6,600 |
Domestic Tax Authority [Member] | Before Tax Year 2018 [Member] |  |
Operating Loss Carryforwards | 114,900 |
Domestic Tax Authority [Member] | Tax Years 2018 to 2022 [Member] |  |
Operating Loss Carryforwards | 231,500 |
State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards | 167,900 |
State and Local Jurisdiction [Member] | Research Tax Credit Carryforward [Member] |  |
Tax Credit Carryforward, Amount | $ 4,100 |

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