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Fair Value Measurements - Estimated Fair Value of Equity Securities Assumptions (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 Y $ / shares item shares | Dec. 31, 2018 item Y
Fair Value Measurements |  |
Valuation assumptions, measurement input | Y |  | 1.45
Number of tranches | 2 |
License Agreement and 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 |
Closing common stock price | OTC exchange |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input | $ / shares | 0.12 |
Discount for lack of marketability |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input |  | 0.35
Discount for lack of marketability | Tranche 1 |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input | 0.13 |
Discount for lack of marketability | Tranche 2 |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input | 0.33 |
Estimated time to liquidity of shares | Tranche 1 |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input | Y | 0.25 |
Estimated time to liquidity of shares | Tranche 2 |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input | Y | 1.5 |
Liquidation |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input |  | 0.20
Near-term sale |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input |  | 0.05
Near-term financing |  |
Fair Value Measurements |  |
Valuation assumptions, measurement input |  | 0.75

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