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Stockholders' Equity - Additional Information (Detail) |  | 1 Months Ended | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | ---
Aug. 17, 2018 USD ($) | Aug. 31, 2019 shares | Mar. 31, 2019 USD ($) $ / shares shares | Jun. 30, 2020 USD ($) Vote | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Mar. 31, 2019 USD ($) $ / shares shares | Jun. 30, 2020 Vote
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Number of common stock voting entitlement per share | Vote |  |  |  | 1 |  |  |  | 1
Proceeds from private offering of shares of common stock and warrants |  |  | $ 23,319,156 |  |  |  | $ 23,319,156 |
Net of issuance costs from offering of shares |  |  | $ 1,680,844 |  | $ 141,322 | $ 339,081 |  |
Class of warrant or right, number of securities called by warrants or rights | shares |  |  | 1,666,666 |  |  |  | 1,666,666 |
Class of warrant or right, exercise price of warrants or rights | $ / shares |  |  | $ 10.00 |  |  |  | $ 10.00 |
Proceeds from at the market offering of shares of common stock and warrants |  |  |  | $ 9,216,611 | 5,506,880 | $ 4,557,693 |  |
Common stock outstanding abstract |  |  |  |  |  |  |  | Our outstanding common shares typically include shares that are deemed delivered under US GAAP. Shares that are deemed delivered currently include shares that have vested, but have not yet been delivered, under tax-deferred equity awards, as well as shares purchased under our Employee Stock Purchase Program (“ESPP”) where actual transfer of shares normally occurs a few days after the completion of the purchase periods. There are no voting rights for shares that are deemed delivered under US GAAP until the actual delivery of shares takes place.
Common Stock [Member] |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Proceeds from private offering of shares of common stock and warrants |  |  |  |  |  |  | $ 33 |
Proceeds from at the market offering of shares of common stock and warrants |  |  |  | $ 33 | $ 44 |  |  |
RSU Rescission Agreements [Member] | Common Stock [Member] |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Number of shares returned | shares |  | 38,666 |  |  |  |  |  |
Consummation of Offering Under Shelf Registration [Member] |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Proceeds from shelf registration debt or equity securities | $ 75,000,000 |  |  |  |  |  |  |

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