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Fair Value Measurements - Summary of Changes In Estimated Fair Value of Level 3 Financial Assets (Details) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jan. 01, 2020 shares | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Dec. 31, 2020 item
Changes in the estimated fair value of Level 3 financial assets |  |  |  |  |  |
Transfer out of Level 3 | $ (2,310) |  | $ 0 |  | $ 0 |
Significant Unobservable Inputs (Level 3) [Member] |  |  |  |  |  |
Changes in the estimated fair value of Level 3 financial assets |  |  |  |  |  |
Balance at beginning of period |  |  |  | $ 1,693 |  |
Change in fair value |  |  |  | 617 |  |
Transfer out of Level 3 |  |  |  | $ (2,310) |  |
License Agreement and Common Stock Purchase Agreement [Member] | Rezolute [Member] |  |  |  |  |  |
Changes in the estimated fair value of Level 3 financial assets |  |  |  |  |  |
Number of Rezolute's post-split shares Company has right and option to sell | shares |  | 100,000 |  |  |  |
Number of tranches | item |  |  |  |  |  | 2

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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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