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Related Party Agreements (Narrative) (Details) - Fortress Biotech, Inc - USD ($) |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 02, 2024 | Jul. 22, 2016 | Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Related Party Transaction [Line Items] |  |  |  |  |  |  |
Shares issued for services (in shares) | 353,086 |  |  |  |  |  |
Parent Company | Management Services Agreement (MSA) |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |
Percentage of annual fees expense related to Management Services Agreement recorded in research and development expenses |  |  | 50.00% |  |  | 50.00% |
Percentage of annual fees expense related to Management Services Agreement recorded in general and administrative expenses |  |  | 50.00% |  |  | 50.00% |
Expenses from related party transaction |  |  | $ 100,000 | $ 100,000 | $ 300,000 | $ 300,000 |
Parent Company | Founders Agreement |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |
Shares issued for services (in shares) |  |  |  |  | 575,191 |  |
Percentage of fully diluted equity | 2.50% | 2.50% |  |  |  |  |
Expenses from related party transaction |  |  | $ 163,000 | $ 0 | $ 163,000 | $ 0 |
Research and development for licenses acquired |  |  |  |  |  |  | $ 500,000

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