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v3.21.2

Fair value of financial assets and liabilities - Rollforward of the Aggregate Fair Values (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Conversion of preferred stock warrants to common stock warrants |  |  | $ 23,760 |
Preferred stock warrant liability |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | $ 15,600 | $ 3,499 | 4,117 | $ 3,396
Change in fair value | 8,160 |  | 19,643 | (549)
Conversion of preferred stock warrants to common stock warrants | (23,760) |  | (23,760) |
Balance, end of period |  | 3,499 |  | 3,499
Preferred stock warrant liability | Series C1 preferred Stock Warrants |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Initial fair value | $ 0 | $ 0 | $ 0 | $ 652

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- Definition Amount of issuances 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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