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Convertible Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  | 6 Months Ended |
--- | --- | --- | ---
Jan. 09, 2020 | Jun. 30, 2020 | Jun. 16, 2020
Common Stock [Member] |  |  |
Temporary Equity [Line Items] |  |  |
Shares issued upon conversion |  |  | 27,094,085
Series C Convertible Preferred Stock [Member] |  |  |
Temporary Equity [Line Items] |  |  |
Shares issued during the period | 19,936,296 |  |
Shares issued price | $ 5.5914 |  |
Gross proceeds | $ 111,500 |  |
Stock issuance of costs | $ 2,600 | $ 2,640 |

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