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Description of Business and Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Jun. 16, 2020 USD ($) $ / shares shares | Jun. 04, 2020 | Jun. 30, 2020 USD ($) shares | Jun. 30, 2020 USD ($) shares | Jun. 30, 2020 USD ($) shares | Jun. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) shares
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Proceeds from the IPO, net of underwriting discounts, commissions and estimated offering costs | $ |  |  |  |  | $ 298,080 | $ 0 |
Common stock, shares authorized | 400,000,000 |  | 400,000,000 | 400,000,000 | 400,000,000 |  | 52,042,000
Preferred stock, shares authorized | 40,000,000 |  | 40,000,000 | 40,000,000 | 40,000,000 |  | 0
Reverse stock split, description |  |  |  |  | On June 4, 2020, the Company effected a one-for-2.1095 reverse stock split of its common stock (the Reverse Stock Split). |  |
Stockholders' equity note, stock split, conversion ratio |  | 2.1095 |  |  |  |  |
Accumulated deficit | $ |  |  | $ 38,826 | $ 38,826 | $ 38,826 |  | $ 22,185
Cash and cash equivalents | $ |  |  | $ 352,446 | $ 352,446 | $ 352,446 |  | $ 94,578
Common Stock |  |  |  |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Outstanding shares of convertible preferred stock converted into common stock |  |  |  | 17,921,000 |  |  |
Initial Public Offering |  |  |  |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Sale of stock number of shares issued in transaction | 16,560,000 |  |  |  |  |  |
Sale of stock, price per share | $ / shares | $ 18.00 |  |  |  |  |  |
Proceeds from the IPO, net of underwriting discounts, commissions and estimated offering costs | $ | $ 274,100 |  |  |  |  |  |
Outstanding shares of convertible preferred stock converted into common stock | 17,921,069 |  |  |  |  |  |
Initial Public Offering | Undesignated Preferred Stock |  |  |  |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Preferred stock, shares authorized | 40,000,000 |  |  |  |  |  |
Initial Public Offering | Common Stock |  |  |  |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |
Outstanding shares of convertible preferred stock converted into common stock |  |  | 17,921,069 |  |  |  |
Warrant to purchase of common stock | 7,809 |  |  |  |  |  |
Common stock, shares authorized | 400,000,000 |  |  |  |  |  |

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