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Warrants - Outstanding Warrants To Purchase Common Stock Warrants (Detail) - Common Stock | 3 Months Ended
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Mar. 31, 2021 $ / shares shares
Class of Warrant or Right [Line Items] |
Number of shares underlying warrants (in shares) | 6,264
Original issue date of April 2016 |
Class of Warrant or Right [Line Items] |
Exercise price (in dollars per share) | $ / shares | $ 1.12
Number of shares underlying warrants (in shares) | 6,264
Original issue date of April 2016 | Remaining Term (in years) |
Class of Warrant or Right [Line Items] |
Original Term | 7 years

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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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