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Significant Accounting Policies (Narrative) (Details) |  |  |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2024 shares | Jan. 01, 2023 shares | Jul. 22, 2016 shares | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) item segment | Dec. 31, 2022 USD ($)
Significant Accounting Policies |  |  |  |  |  |  |  |  |
Number of subsidiaries | item |  |  |  |  |  |  |  | 0 |
Number of operating segments | segment |  |  |  |  |  |  |  | 1 |
Number of reportable segments | segment |  |  |  |  |  |  |  | 1 |
Restricted cash |  |  |  | $ 375,000 | $ 750,000 | $ 375,000 | $ 750,000 | $ 750,000 | $ 1,000,000
Estimated useful life |  |  |  |  |  |  |  | 5 years |
Total property, plant and equipment |  |  |  | 7,694,000 |  | 7,694,000 |  | $ 7,723,000 |
Research and development |  |  |  | $ 57,000 | $ 9,527,000 | $ 8,221,000 | $ 34,363,000 | 40,513,000 | 62,475,000
Accumulated other comprehensive loss |  |  |  |  |  |  |  | 0 |
Construction in process |  |  |  |  |  |  |  |  |
Significant Accounting Policies |  |  |  |  |  |  |  |  |
Total property, plant and equipment |  |  |  |  |  |  |  | $ 29,000 |
Total property, plant and equipment |  |  |  |  |  |  |  |  | $ 1,000,000
Fortress Biotech, Inc |  |  |  |  |  |  |  |  |
Significant Accounting Policies |  |  |  |  |  |  |  |  |
Common stock dividend issued (in shares) | shares | 7,061 | 3,742 |  |  |  |  |  |  |
Percentage of fully diluted equity | 2.50% | 2.50% |  |  |  |  |  | 2.50% | 2.50%
Fortress Biotech, Inc | License agreements |  |  |  |  |  |  |  |  |
Significant Accounting Policies |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  |  | $ 500,000 | $ 1,100,000
Fortress Biotech, Inc | Class A Preferred Shares |  |  |  |  |  |  |  |  |
Significant Accounting Policies |  |  |  |  |  |  |  |  |
Preferred stock dividends issued (in shares) | shares |  |  | 250,000 |  |  |  |  |  |
Percentage of fully diluted equity |  |  | 2.50% |  |  |  |  |  |

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