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The Company and its Significant Accounting Policies - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended |
--- | --- | --- | ---
Jun. 09, 2020 | Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Company And Significant Accounting Policies [Line Items] |  |  |  |
Entity incorporation date |  | Aug. 05, 1999 |  |
Cash and cash equivalents |  | $ 13,912 |  | $ 22,141
Net loss |  | $ 9,280 | $ 9,964 |
2020 Offering |  |  |  |
Company And Significant Accounting Policies [Line Items] |  |  |  |
IPO closing date |  | Jun. 09, 2020 |  |
Common Stock | 2020 Offering |  |  |  |
Company And Significant Accounting Policies [Line Items] |  |  |  |
Issuance of common stock, net of issuance costs, shares | 36,800,000 |  |  |
Shares issued and sold, price per share | $ 0.75 |  |  |
Proceeds from issuance of public offering | $ 25,086 |  |  |
Underwriting discounts and commissions | 1,656 |  |  |
Offering expenses paid | $ 719 |  |  |

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