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Income Taxes (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Operating Loss Carryforwards [Line Items] |  |  |
U.S. federal statutory income tax rate | 21.00% | 21.00% | 21.00%
Operating loss carryforwards indefinitely | $ 13,016,000 |  |
Operating loss carryforwards, limitations on use | The Company also has indefinite life carryforwards as a result of interest limitations. Starting in 2022, the Company has research costs attributable to research and development that are currently expensed but are required to be capitalized for U.S. tax purposes and amortized primarily over 5 or 15 years. |  |
Period of unrecognized tax benefits not expected to be changed | 12 months |  |
Interest and penalties recorded | $ 0 | $ 0 | $ 0
Proposed global minimum tax percentage | 15.00% |  |
Deferred tax assets valuation allowance | $ 6,558,000 | 6,012,000 |
Minimum [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Research and development expense amortized period | 5 years |  |
Maximum [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Research and development expense amortized period | 15 years |  |
Domestic Tax Authority [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Loss carryforwards for federal income tax purposes | $ 14,012,000 | 54,376,000 |
Operating loss carryforwards expiration amount | $ 996,000 |  |
Operating loss carryforwards expiration year | 2037 |  |
Deferred tax assets valuation allowance | $ 0 | 0 |
State and Local Jurisdiction [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Loss carryforwards for federal income tax purposes | 182,445,000 | 188,884,000 |
Valuation allowance for net operating loss carryforwards | $ 6,558,000 | $ 5,988,000 |
State and Local Jurisdiction [Member] | Minimum [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards expiration year | 2027 |  |
State and Local Jurisdiction [Member] | Maximum [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards expiration year |  | 2043 |
Foreign Tax Authority [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Loss carryforwards for federal income tax purposes | $ 0 | $ 69,000 |
Valuation allowance for net operating loss carryforwards | $ 0 | $ 24,000 |
Foreign Tax Authority [Member] | Minimum [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards expiration year | 2023 |  |
Foreign Tax Authority [Member] | Maximum [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Operating loss carryforwards expiration year | 2028 |  |

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