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Fair Value Measurements - Additional Information (Details) - USD ($) | 3 Months Ended | 12 Months Ended
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Mar. 31, 2019 | Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Changes in estimated fair value of contingent consideration | $ 0 |
Rezolute [Member] | Common Stock Purchase Agreement [Member] | Forecast [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Maximum number of shares of common stock sold back |  | 5,000,000

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