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Stockholders' Equity (Registration Statements, At-the-Market Offering and Stock Issuances to Fortress) (Details) |  |  |  | 1 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 19, 2024 $ / shares shares | Jan. 01, 2024 shares | May 24, 2021 USD ($) shares | Oct. 31, 2024 USD ($) shares | Jul. 31, 2016 | Dec. 31, 2024 USD ($) item $ / shares shares | Dec. 31, 2023 USD ($) $ / shares shares | Jun. 12, 2024 USD ($) | May 31, 2024 | Dec. 31, 2022 shares | Jul. 13, 2018 | Dec. 31, 2016 USD ($) shares
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized | shares |  |  |  |  |  | 200,000,000 | 200,000,000 |  |  |  |  |
Common stock par value (in dollars per share) | $ / shares |  |  |  |  |  | $ 0.0001 | $ 0.0001 |  |  |  |  |
Preferred stock, shares authorized | shares |  |  |  |  |  | 2,000,000 | 2,000,000 |  |  |  |  |
Preferred Stock, Shares Issued | shares |  |  |  |  |  | 250,000 | 250,000 |  |  |  |  |
Common stock subscribed (in shares) | shares |  |  |  |  |  | 69,046 | 7,061 |  |  |  |  |
Aggregate value of shares subscribed | $ |  |  |  |  |  | $ 611,000 | $ 591,000 |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  | 6,512,000 | 4,398,000 |  |  |  |  |
Aggregate fees of stock issuance | $ |  |  |  |  |  | 1,353,000 | 443,000 |  |  |  |  |
Deemed dividend for issuance of warrants | $ |  |  |  | $ 7,800,000 |  |  |  |  |  |  |  |
Research and development - licenses acquired | $ |  |  |  |  |  | $ 861,000 | $ 527,000 |  |  |  |  |
At the Market Offering |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Agent commission (as a percent) |  |  |  |  |  |  |  |  | 3.00% |  | 3.00% |
Issuance of common shares (in shares) | shares |  |  |  |  |  | 140,000 | 1,034 |  |  |  |  |
Price per common stock | $ / shares |  |  |  |  |  | $ 18.78 | $ 158.07 |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  | $ 2,600,000 | $ 163,000 |  |  |  |  |
Aggregate fees of stock issuance | $ |  |  |  |  |  | 100,000 | 3,000 |  |  |  |  |
Proceeds from issuance of Common Stock, net of offering costs | $ |  |  |  |  |  | 2,500,000 | $ 160,000 |  |  |  |  |
Registration Statements | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Shelf Registration statement, value of securities authorized to be sold | $ |  |  | $ 200,000,000 |  |  |  |  |  |  |  |  |
2021 S-3 |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common shares (in shares) | shares |  |  | 4,400,000 |  |  |  |  |  |  |  |  |
2024 S-3 |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Sale of Stock aggregate offering price | $ |  |  |  |  |  |  |  | $ 40,000,000 |  |  |  |
Shares available for future issuance | $ |  |  |  |  |  | $ 34,800,000 |  |  |  |  |  |
June 2024 Registered Direct Offering |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common shares (in shares) | shares | 60,500 |  |  |  |  |  |  |  |  |  |  |
Price per common stock | $ / shares | $ 20.5 |  |  |  |  |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Number of votes per share | item |  |  |  |  |  | 1 |  |  |  |  |  |
Class A common shares |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized | shares |  |  |  |  |  |  |  |  |  | 1,000,000 |  |
Director appointment right, period |  |  |  |  |  | 10 years |  |  |  |  |  |
Class A Preferred Shares |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Shares Issued | shares |  |  |  |  |  | 250,000 |  |  |  |  |  |
Series A-3 warrant |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issuable upon exercise of warrants shares | shares |  |  |  | 337,552 |  |  |  |  |  |  |  |
Exercise of warrants (in shares) | shares |  |  |  | 82,000 |  |  |  |  |  |  |  |
Class of warrant or right, shares held in abeyance | shares |  |  |  | 255,552 |  | 185,880 |  |  |  |  |  |
Fortress Biotech, Inc |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Aggregate value of shares subscribed | $ |  |  |  |  |  |  |  |  |  |  |  | $ 900
Shares issued for services (in shares) | shares |  | 7,061 |  |  |  | 23,450 | 1,319 |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  |  | $ 200,000 |  |  |  |  |
Percentage of fully diluted equity |  |  |  |  |  | 2.50% | 2.50% |  |  |  |  |
Fortress Biotech, Inc | At the Market Offering |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Common stock subscribed (in shares) | shares |  |  |  |  |  |  | 25 |  |  |  |  |
Shares issued for services (in shares) | shares |  |  |  |  |  | 3,509 |  |  |  |  |  |
Price per common stock | $ / shares |  |  |  |  |  | $ 18.78 |  |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  | $ 2,600,000 | $ 4,400,000 |  |  |  |  |
Fortress Biotech, Inc | May 2024 Equity Offering |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  | 4,000,000 |  |  |  |  |  |
Fortress Biotech, Inc | June 2024 Registered Direct Offering |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  | 2,500,000 |  |  |  |  |  |
Fortress Biotech, Inc | October registered direct offering |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  |  | $ 4,000,000 |  |  |  |  |  |
Fortress Biotech, Inc | Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Common stock subscribed (in shares) | shares |  |  |  |  |  |  |  |  |  |  |  | 2,666
Fortress Biotech, Inc | Class B Common Shares |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Common stock subscribed (in shares) | shares |  |  |  |  |  |  |  |  |  |  |  | 7,000,000
Fortress Biotech, Inc | Class A Preferred Shares |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |  |  |
Percentage of fully diluted equity |  |  |  |  | 2.50% |  |  |  |  |  |  |

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