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Related Party Agreements (Narrative) (Details) - USD ($) $ in Thousands |  |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Mar. 04, 2022 | Jan. 01, 2022 | Jul. 22, 2016 | Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Related Party Transaction [Line Items] |  |  |  |  |  |
Common stock, shares issuable |  |  |  | 27,393 |  | 2,536,607
Proceeds from debt issuance |  |  |  | $ 30,000 | $ 0 |
Runway Debt Facility |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Warrant term | 10 years |  |  |  |  |
Proceeds from debt issuance | $ 30,000 |  |  |  |  |
At the Market Offering [Member] |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Proceeds from issuance of common shares |  |  |  | $ 2,800 | $ 48,400 |
Fortress Biotech, Inc [Member] |  |  |  |  |  |
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% |
Shares issued for services (in shares) |  | 2,536,607 |  | 1,049,302 |  |
Common stock, shares issuable |  |  |  | 27,393 |  |
Proceeds from issuance of common shares |  |  |  | $ 2,800 |  |
Percentage of fully diluted equity |  | 2.50% | 2.50% | 2.50% |  |
Expenses from related party transaction |  |  |  | $ 300 | $ 100 |
Fortress Biotech, Inc [Member] | Research and development [Member] |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Expenses from related party transaction |  |  |  |  |  | $ 4,200
Fortress Biotech, Inc [Member] | General and administrative [Member] |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Expenses from related party transaction |  |  |  | $ 800 | $ 1,200 |

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- Definition Amount of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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