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v3.20.2

Nature of Business, Basis of Presentation and Going Concern Uncertainty - Additional Information (Detail) $ in Thousands |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Jul. 31, 2020 shares | Jun. 30, 2020 USD ($) shares | Mar. 31, 2020 USD ($) | Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Jun. 30, 2020 USD ($) shares | Jun. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) shares
Nature Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |  |
Common stock, shares authorized | shares |  | 150,000,000 |  |  |  | 150,000,000 |  | 150,000,000
Accumulated deficit |  | $ (51,946) |  |  |  | $ (51,946) |  | $ (45,704)
Net loss |  | (2,922) | $ (3,320) | $ (3,624) | $ (5,904) | (6,242) | $ (9,528) |
Cash and cash equivalents |  | 12,111 |  |  |  | 12,111 |  | $ 16,664
Working capital |  | $ 10,800 |  |  |  | 10,800 |  |
Net cash used in operations |  |  |  |  |  | $ 6,659 | $ 8,730 |
Subsequent Event [Member] |  |  |  |  |  |  |  |
Nature Of Business And Basis Of Presentation [Line Items] |  |  |  |  |  |  |  |
Reverse stock split ratio | 0.05 |  |  |  |  |  |  |
Common stock, shares authorized | shares | 150,000,000 |  |  |  |  |  |  |

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