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Stockholders Equity (Common Stock and Equity Offerings) (Narrative) (Details) |  |  |  |  | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 30, 2023 USD ($) | Oct. 26, 2023 $ / shares shares | Mar. 15, 2023 | Mar. 03, 2023 $ / shares | Sep. 30, 2023 USD ($) $ / shares shares | Sep. 30, 2022 USD ($) $ / shares shares | Dec. 31, 2022 $ / shares shares | May 24, 2021 USD ($) | Dec. 04, 2020 USD ($) | Aug. 31, 2018
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio |  |  | 0.0667 |  |  |  |  |  |  |
Preferred stock par value (in dollars per share) | $ / shares |  |  |  | $ 0.0001 | $ 0.0001 |  | $ 0.0001 |  |  |
Number of fractional shares issued in connection with the Reverse Stock Split |  |  |  |  | 0 |  |  |  |  |
Common stock, shares issuable |  |  |  |  | 6,987 |  | 187,134 |  |  |
Shares available for future sale |  |  |  |  | 380,089 |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio |  |  |  | 0.20 |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio |  |  |  | 0.05 |  |  |  |  |  |
At the Market Offering [Member] |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Agent commission (as a percent) |  |  |  |  |  |  |  |  |  | 3.00%
Issuance of common shares (in shares) |  |  |  |  | 52,000 | 525,000 |  |  |  |
Shares issued, price per share | $ / shares |  |  |  |  | $ 3.15 | $ 12.61 |  |  |  |
Proceeds from issuance of common shares | $ |  |  |  |  | $ 200,000 | $ 6,600,000 |  |  |  |
Aggregate fees of stock issuance | $ |  |  |  |  | 3,000 | $ 100,000 |  |  |  |
Registration Statements [Member] |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Sale of Stock aggregate offering price - Founders Agreement | $ |  |  |  |  |  |  |  | $ 200,000,000.0 | $ 100,000,000.0 |
Shares available for future issuance - Founders Agreement | $ |  |  |  |  | $ 7,800,000 |  |  |  |  |
Subsequent event | Registration Statements [Member] |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Amount for issued and sale of registered direct offering | $ | $ 4,400,000 |  |  |  |  |  |  |  |  |
Issuance of common shares (in shares) |  | 920,000 |  |  |  |  |  |  |  |
Shares issued, price per share | $ / shares |  | $ 1.70 |  |  |  |  |  |  |  |
Aggregate fees of stock issuance | $ | $ 500,000 |  |  |  |  |  |  |  |  |
Fortress Biotech, Inc [Member] |  |  |  |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |  |  |  |
Issuance of common shares (in shares) |  |  |  |  | 0 | 13,131 |  |  |  |
Shares issued, price per share | $ / shares |  |  |  |  |  | $ 13.56 |  |  |  |
Common stock, shares issuable |  |  |  |  | 1,297 |  |  |  |  |

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