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Fair Value Measurements - Estimated Fair Value of Equity Securities Assumptions (Details) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 shares | Dec. 31, 2019 $ / shares Y shares | Sep. 30, 2020 $ / shares Y item
Common Stock Purchase Agreement | Rezolute |  |  |
Fair Value Measurements |  |  |
Number of Rezolute's shares Company has right and option to sell if Rezolute does not list common stock shares on national exchange | shares | 5,000,000 | 5,000,000 |
Number of tranches | item |  |  | 2
Closing common stock price | OTC exchange |  |  |
Fair Value Measurements |  |  |
Valuation assumptions, measurement input | $ / shares |  | 0.12 | 0.43
Discount for lack of marketability | Tranche 1 |  |  |
Fair Value Measurements |  |  |
Valuation assumptions, measurement input |  | 0.13 | 0.12
Discount for lack of marketability | Tranche 2 |  |  |
Fair Value Measurements |  |  |
Valuation assumptions, measurement input |  | 0.33 | 33
Estimated time to liquidity of shares | Tranche 1 |  |  |
Fair Value Measurements |  |  |
Valuation assumptions, measurement input |  | 0.25 | 0.25
Estimated time to liquidity of shares | Tranche 2 |  |  |
Fair Value Measurements |  |  |
Valuation assumptions, measurement input |  | 1.5 | 1.25

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