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Income Taxes (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2017
Income Tax [Line Items] |  |  |
Net operating loss carryforwards | $ 179,500,000 |  |
Tax Credit Carryforward, Description | The net operating loss carryforwards beginning in 2018, have no expiration. |  |
Valuation allowance | $ 47,000,000 |  |
Increase in net deferred tax assets and liabilities | 2,400,000 |  |
Decrease in deferred tax assets and liabilities | $ 100,000 |  |
Federal statutory income tax rate | 21.00% | 21.00% |
Reserve for uncertain tax positions | $ 0 | $ 0 |
Interest or penalties recognized | $ 0 | $ 0 |
Open tax year | 2009 |  |
Research Tax Credit Carryforward |  |  |
Income Tax [Line Items] |  |  |
Research and experimentation credits | $ 1,900,000 |  |
Operating loss carryforwards, limitations on use | Utilization of net operating losses and tax credits, including those acquired as a result of the Merger, will be subject to an annual limitation due to ownership change limitations provided by Internal Revenue Code Section 382. The Company believes that an ownership change limitation as defined under Section 382 of the U.S. Internal Revenue Code occurred as a result of its various historical financing transactions. Future utilization of the federal net operating losses and tax credit carryforwards accumulated from June 2005 to the change in ownership date will be subject to annual limitations to offset future taxable income. The annual limitation may result in the expiration of the net operating losses and credits before utilization. As such, a portion of the Company’s net operating loss carryforwards may be limited |  |
Tax credit carryforward, limitations on use | Utilization of net operating losses and tax credits, including those acquired as a result of the Merger, will be subject to an annual limitation due to ownership change limitations provided by Internal Revenue Code Section 382. The Company believes that an ownership change limitation as defined under Section 382 of the U.S. Internal Revenue Code occurred as a result of its various historical financing transactions. Future utilization of the federal net operating losses and tax credit carryforwards accumulated from June 2005 to the change in ownership date will be subject to annual limitations to offset future taxable income. The annual limitation may result in the expiration of the net operating losses and credits before utilization. As such, a portion of the Company’s net operating loss carryforwards may be limited |  |
Earliest Tax Year |  |  |
Income Tax [Line Items] |  |  |
Operating loss carryforwards expiration year |  |  | 2025
Latest Tax Year |  |  |
Income Tax [Line Items] |  |  |
Operating loss carryforwards expiration year |  |  | 2037

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