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Warrants - Outstanding Warrants To Purchase Common Stock Warrants (Detail) - Common Stock	3 Months Ended
	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

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