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Net Loss per Share - Additional Information (Detail) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Nov. 29, 2019	Apr. 16, 2019
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Weighted average common shares outstanding—basic and diluted (in shares)	26,609,000	20,085,000	24,667,000	20,035,000
Pre Funded Warrant
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Exercise Price (usd per share)					$ 11.999	$ 10.999
Pre Funded Warrant | Maximum
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Exercise Price (usd per share)	$ 0.01		$ 0.01
Redeemable Common Stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Weighted average common shares outstanding—basic and diluted (in shares)	229,885

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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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