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v3.20.4

Description of Business - Additional Information (Details) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 01, 2021 USD ($) | Jan. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) $ / shares | Dec. 31, 2019 USD ($) $ / shares
Description Of Business [Line Items] |  |  |  |
Date of incorporation |  |  | Mar. 13, 2014 |
Class A common stock, par value | $ / shares |  |  | $ 0.001 | $ 0.001
Reverse stock split |  |  | 1-for-35 |
Reverse stock split, conversion ratio |  |  | 35 |
Cash |  |  | $ 3,331 | $ 5,459
Net loss |  |  | 14,130 | 9,781
Accumulated deficit |  |  | 118,903 | 104,773
Revenue from the sale of products or services |  |  | $ 661 | $ 1,496
Subsequent Event |  |  |  |
Description Of Business [Line Items] |  |  |  |
Net proceeds from public offering | $ 9,600 |  |  |
Subsequent Event | March 2020 Offering |  |  |  |
Description Of Business [Line Items] |  |  |  |
Net proceeds from exercise of warrants issued |  | $ 1,300 |  |

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