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Stockholders' Equity (Deficit) - Additional Information (Details) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 12 Months Ended | 24 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 20, 2021 $ / shares shares | Jul. 09, 2021 | Jul. 31, 2021 shares | Jan. 31, 2021 USD ($) $ / shares shares | Apr. 30, 2020 USD ($) $ / shares shares | Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) $ / shares shares | Dec. 31, 2018 $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares | Feb. 28, 2021 shares | Apr. 15, 2020 $ / shares shares
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  | 800,000,000 | 147,027,681 |  |  | 156,000,000 | 147,027,681
Common stock, par value | $ / shares |  |  |  |  |  | $ 0.0001 | $ 0.0001 |  |  |  | $ 0.0001
Undesignated preferred stock authorized |  |  |  |  |  | 80,000,000 | 0 |  |  |  |
Undesignated preferred stock par value | $ / shares |  |  |  |  |  | $ 0.0001 | $ 0.0001 |  |  |  |
Proceeds from issuance of convertible preferred stock | $ |  |  |  |  |  | $ 119,393 | $ 136,975 |  |  |  |
Series B-1 convertible preferred shares converted into common stock |  | 1.2 |  |  |  |  |  |  |  |  |
Preferred stock purchase right liability | $ |  |  |  |  |  |  | $ 1,615 |  |  |  |
Shares issued and sold |  |  |  |  |  | 121,382,547 | 25,189,673 |  |  |  |
Common stock, shares outstanding |  |  |  |  |  | 119,102,505 | 21,923,173 |  |  |  |
Shares of common stock subject to repurchase |  |  |  |  |  | 212,674 | 577,259 |  |  |  |
Number of shares vested |  |  |  |  |  | 364,585 | 364,582 |  |  |  |
Share-based compensation, vesting rights description |  |  |  |  |  | The restricted stock vests 25% one year from the vesting commencement date and monthly thereafter over a three-year period and is subject to repurchase by the Company in the event of any voluntary or involuntary termination of services to the Company prior to vesting. |  |  |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock converted into shares of common stock |  |  |  |  |  | 71,263,685 |  |  |  |  |
Shares issued and sold |  |  |  |  |  | 121,382,547 | 25,189,673 |  | 22,629,158 |  |
IPO |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized | 800,000,000 |  |  |  |  |  |  |  |  | 156,000,000 |
Undesignated preferred stock authorized | 80,000,000 |  |  |  |  |  |  |  |  |  |
Undesignated preferred stock par value | $ / shares | $ 0.0001 |  |  |  |  |  |  |  |  |  |
IPO | Common Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock converted into shares of common stock | 71,263,685 |  | 71,263,685 |  |  |  |  |  |  |  |
Restricted Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares issued |  |  |  |  |  |  |  | 1,458,332 |  |  |
Share price per share | $ / shares |  |  |  |  |  |  |  | $ 0.0001 |  |  |
Stock vesting period |  |  |  |  |  |  |  | 3 years |  |  |
Restricted Stock | One Year from the Vesting Commencement Date and Monthly Thereafter Over Three-year Vesting Period |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock vesting percentage |  |  |  |  |  |  |  | 25.00% |  |  |
Share-based compensation, vesting rights description |  |  |  |  |  | The Company granted 1,795,827 shares of its restricted stock in 2018, which vest 25% one year from the vesting commencement date and monthly thereafter over a three-year period. |  |  |  |  |
Series B Agreement |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Purchase agreement termination date |  |  |  |  | Sep. 30, 2022 |  |  |  |  |  |
Series B-1 convertible preferred shares converted into common stock |  |  |  |  | 0.1 |  |  |  |  |  |
Series A Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  |  |  |  |  | 38,103,681 | 38,103,681 | 38,103,681 |  |
Convertible preferred stock, issue price per share | $ / shares |  |  |  |  |  |  |  | $ 1.667 | $ 1.667 |  |
Proceeds from issuance of convertible preferred stock | $ |  |  |  |  |  |  |  |  | $ 63,400 |  |
Preferred shares outstanding |  |  |  |  |  |  | 38,103,681 |  |  |  |
Series B-1 Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  |  |  |  |  | 27,481,001 |  |  |  |
Preferred shares outstanding |  |  |  |  |  |  | 27,481,001 |  |  |  |
Series B-1 Convertible Preferred Stock | Series B Agreement |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  |  |  | 27,481,001 |  |  |  |  |  |
Convertible preferred stock, issue price per share | $ / shares |  |  |  |  | $ 5.00 |  |  |  |  |  |
Proceeds from issuance of convertible preferred stock | $ |  |  |  |  | $ 137,000 |  |  |  |  |  |
Series B-2 Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  |  |  |  |  | 4,000,000 |  |  |  |
Convertible preferred stock, issue price per share | $ / shares |  |  |  | $ 7.50 |  |  | $ 7.50 |  |  |  |
Proceeds from issuance of convertible preferred stock | $ |  |  |  | $ 119,400 |  |  |  |  |  |  |
Preferred stock purchase right liability | $ |  |  |  |  |  | $ 9,000 |  |  |  |  |
Gain (loss) for changes in fair value of convertible preferred stock purchase right liability | $ |  |  |  |  |  |  | $ 7,400 |  |  |  |
Convertible preferred stock, shares issued during period |  |  |  | 13,175,191 |  |  |  |  |  |  |
Convertible preferred stock, additional shares issued |  |  |  | 2,756,581 |  |  |  |  |  |  |
Convertible preferred stock shares issued in connection with asset acquisition |  |  |  |  |  |  | 4,000,000 |  |  |  |
Preferred shares outstanding |  |  |  |  |  |  | 4,000,000 |  |  |  |
Series B-2 Convertible Preferred Stock | Series B Agreement |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  |  |  | 13,175,191 |  |  |  |  |  |
Convertible preferred stock, issue price per share | $ / shares |  |  |  |  | $ 7.50 |  |  |  |  |  |
Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, shares issued |  |  |  |  |  | 0 | 69,584,682 |  |  |  |
Convertible preferred stock, shares issued during period |  |  |  |  |  | 15,931,772 | 27,481,001 |  |  |  |
Preferred shares outstanding |  |  |  |  |  | 0 | 69,584,682 |  | 38,103,681 |  |

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