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Common Stock Warrants - Additional Information (Detail) - $ / shares |  |  |  | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Nov. 29, 2019 | Nov. 26, 2019 | Apr. 16, 2019 | Sep. 30, 2021 | Mar. 23, 2021 | Dec. 31, 2020
Class of Stock [Line Items] |  |  |  |  |  |
Issued |  |  |  | 50,000 |  |
Class of warrants or rights expiration period (in years) |  | 30 days |  |  |  |
Common stock, par value (in usd per share) |  |  |  | $ 0.001 |  | $ 0.001
Number of Shares of Common Stock Issuable (in shares) |  |  |  | 11,249,128 |  | 13,354,403
Class A Warrant |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Issued |  |  | 3,900,000 |  |  |
Warrant exercise price (usd per share) |  |  | $ 13.20 |  |  |
Class B Warrants |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Issued | 5,416,667 |  |  |  |  |
Warrant exercise price (usd per share) | $ 15.00 |  |  |  | $ 8.70 |
Pre Funded Warrant |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Issued | 1,750,000 |  | 2,130,000 |  |  |
Warrant exercise price (usd per share) | $ 11.999 |  | $ 10.999 |  |  |
Number of warrants for purchase of convertible preferred shares (in shares) |  |  | 1 |  |  |
Common stock, par value (in usd per share) |  |  | $ 0.001 |  |  |

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- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 + Details
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