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Fair value of financial assets and liabilities - Financial Assets and Liabilities Measured at Fair Value (Details) - Recurring - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Assets |  |
Cash equivalents | $ 212,833 | $ 23,456
Short-term investments |  | 14,998
Assets | 212,833 | 38,454
Liabilities |  |
Preferred stock warrant liability |  | 4,117
Liabilities |  | 4,117
Level 1 |  |
Assets |  |
Cash equivalents | 212,833 | 23,456
Short-term investments |  | 14,998
Assets | $ 212,833 | 38,454
Level 3 |  |
Liabilities |  |
Preferred stock warrant liability |  | 4,117
Liabilities |  | $ 4,117

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + 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 (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + 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 (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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