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Fair Value Measurements - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - Recurring - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Assets |  |
Money market funds | $ 280,099 | $ 85,797
Liabilities |  |
Common stock warrant liability | 420 | 447
Fair Value Measured Using - (Level 1) |  |
Assets |  |
Money market funds | 280,099 | 85,797
Liabilities |  |
Common stock warrant liability | 0 | 0
Fair Value Measured Using - (Level 2) |  |
Assets |  |
Money market funds | 0 | 0
Liabilities |  |
Common stock warrant liability | 0 | 0
Fair Value Measured Using - (Level 3) |  |
Assets |  |
Money market funds | 0 | 0
Liabilities |  |
Common stock warrant liability | $ 420 | $ 447

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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=117815213&loc=d3e19207-110258 + Details
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