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Net Loss per Share - Additional Information (Detail) - shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Preferred shares [Member]
Net Loss per Share [Line Items]
Anti dilutive securities excluded in calculation of earnings per share		6,814,815
Options for purchase of ordinary shares [Member]
Net Loss per Share [Line Items]
Anti dilutive securities excluded in calculation of earnings per share	6,637,830	8,436,900

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- Definition

Net Loss per Share [line item]

+ References

No definition available.

+ Details

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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