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Income Taxes (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2017 | Mar. 31, 2024
Income Taxes (Details) [Line Items] |  |  |  |
Net operating loss carryforwards | $ 208,100,000 |  |  |
Operating loss carryforwards, limitations on use | The net operating loss carryforwards beginning in 2018, have no expiration. |  |  |
Valuation allowance | $ 55,500,000 |  |  |
Increase in net deferred tax assets and liabilities | $ 1,200,000 |  |  |
Federal statutory income tax rate | 21.00% | 21.00% |  |
Open Tax Year | 2009 |  |  |
Reserve for uncertain tax positions | $ 0 | $ 0 |  |
Interest or penalties recognized | 0 | $ 0 |  |
Research Tax Credit Carryforward |  |  |  |
Income Taxes (Details) [Line Items] |  |  |  |
Research and experimentation credits | $ 2,400,000 |  |  |
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. ARCA 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 ARCA’s net operating loss carryforwards may be limited. |  |  |
Earliest Tax Year |  |  |  |
Income Taxes (Details) [Line Items] |  |  |  |
Operating loss carryforwards expiration year |  |  | 2025 |
Latest Tax Year |  |  |  |
Income Taxes (Details) [Line Items] |  |  |  |
Operating loss carryforwards expiration year |  |  | 2037 |

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