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Fair Value Measurements - Summary of Changes in Estimated Fair Value of Financial Liabilities (Details) $ in Thousands	9 Months Ended
	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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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)
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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of gain (loss) recognized in income from liability 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
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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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