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Fair Value Measurements - Summary of Changes in Estimated Fair Value of Financial Liabilities (Details) $ in Thousands | 9 Months Ended
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Sep. 30, 2021 USD ($)
Equity warrant investment |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Balance at December 31, 2020 | $ 1,323 |
Changes in fair value | (199) | [1]
Balance at September 30, 2021 | 1,124 |
Fair Value, Inputs, Level 3 | Success Liabilities |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Balance at December 31, 2020 | 5,773 |
Change in fair value | 19,343 | [1]
Balance at September 30, 2021 | $ 25,116 |
[1] | The change in fair value associated with the equity warrant investment is recorded in other income (expense), net and the change in fair value associated with success payment liabilities is recorded in research and development expense.

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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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