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Convertible Preferred Stock and Stockholders' Equity (Deficit) - Additional Information (Details) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 2 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 24, 2020 shares | Jul. 31, 2019 $ / shares shares | Aug. 31, 2019 USD ($) shares | Dec. 31, 2020 USD ($) $ / shares shares | Dec. 31, 2019 USD ($) shares | Sep. 30, 2020 shares | Sep. 29, 2020 shares
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock authorized to sell |  |  |  |  | 142,150,096 |  |
Proceeds from issuance of convertible preferred stock, net of issuance costs | $ |  |  |  |  | $ 54,782 |  |
Shares outstanding |  |  |  |  | 117,809,883 | 0 | 0
Preferred stock voting rights |  |  |  | The holders of Series C Preferred are entitled to elect one director of the Company; the holders of Series B Preferred are entitled to elect three directors of the Company; the holders of Series A-2 Preferred, are entitled to elect one director; the holders of common stock are entitled to elect one director; and holders of common stock and any other class or series of voting stock, exclusively and voting together as a single class on an as-converted basis, are entitled to elect one director. Holders of Series A Preferred are not entitled to a director of the Company. |  |  |
Common stock, voting rights |  |  |  | one |  |  |
Initial Public Offering |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock converted into common stock | 13,085,913 |  |  |  |  |  |
Series C Convertible Preferred Stock |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock authorized to sell |  | 61,773,000 |  |  | 61,773,000 |  |
Convertible preferred stock, price per share | $ / shares |  | $ 1.4693 |  |  |  |  |
Convertible preferred stock, shares issued |  |  | 37,432,787 |  |  |  |
Proceeds from issuance of convertible preferred stock, net of issuance costs | $ |  |  | $ 55,000 |  |  |  |
Convertible preferred stock, price per share | $ / shares |  | $ 1.4693 |  |  |  |  |
Shares outstanding |  |  |  |  | 37,432,787 |  |
Dividends rights, amount per share on each outstanding share payable | $ / shares |  |  |  | $ 0.117544 |  |  |
Convertible preferred stock, price per share | $ / shares |  |  |  | $ 1.4693 |  |  |
Preferred stock voting rights |  |  |  | one |  |  |
Series C Convertible Preferred Stock | Current Liability |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Fair value of preferred stock tranche obligation | $ |  |  |  |  | $ 2,200 |  |
Series B Preferred |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock authorized to sell |  |  |  |  | 76,078,535 |  |
Shares outstanding |  |  |  |  | 76,078,535 |  |
Dividends rights, amount per share on each outstanding share payable | $ / shares |  |  |  | $ 0.06937 |  |  |
Convertible preferred stock, price per share | $ / shares |  |  |  | $ 0.991 |  |  |
Preferred stock voting rights |  |  |  | three |  |  |
Series A-2 |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock authorized to sell |  |  |  |  | 2,018,561 |  |
Shares outstanding |  |  |  |  | 2,018,561 |  |
Dividends rights, amount per share on each outstanding share payable | $ / shares |  |  |  | $ 0.06034 |  |  |
Convertible preferred stock, price per share | $ / shares |  |  |  | $ 0.862 |  |  |
Preferred stock voting rights |  |  |  | one |  |  |
Series A |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock authorized to sell |  |  |  |  | 2,280,000 |  |
Shares outstanding |  |  |  |  | 2,280,000 |  |
Dividends rights, amount per share on each outstanding share payable | $ / shares |  |  |  | $ 0.08 |  |  |
Preferred stock, convertible, conversion price |  |  |  | 8.8527 |  |  |
Convertible preferred stock, price per share | $ / shares |  |  |  | $ 1.00 |  |  |
Series C Preferred, Series B Preferred and Series A-2 Preferred |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Preferred stock, convertible, conversion price |  |  |  | 9.0058 |  |  |
Series A-2 Preferred, Series B Preferred and Series C Preferred |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Preferred stock voting rights |  |  |  | Shares of Series A-2 Preferred, Series B Preferred and Series C Preferred do not have voting rights. |  |  |
Maximum | Series C Convertible Preferred Stock |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock option to purchase additional shares |  | 17,014,902 |  | 17,014,902 |  |  |
Convertible preferred stock option to purchase additional shares after notified, period |  | 30 days |  |  |  |  |
Minimum |  |  |  |  |  |  |
Temporary Equity [Line Items] |  |  |  |  |  |  |
Convertible preferred stock, price per share | $ / shares |  |  |  | $ 14.56 |  |  |
Proceeds from issuance of convertible preferred stock, net of issuance costs | $ |  |  |  | $ 40,000 |  |  |

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