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Net Loss Per Share - Potentially Dilutive Securities Excluded from Diluted Net Loss Per Share (Detail) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share attributable to common stockholders (in shares)	4,451,964	4,396,880
Shares of common stock subject to outstanding options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share attributable to common stockholders (in shares)	2,592,281	2,845,862
Shares of common stock subject to outstanding common stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share attributable to common stockholders (in shares)	6,264	49,006
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share attributable to common stockholders (in shares)	1,853,419	1,502,012

X

- 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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- Definition

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+ References

No definition available.

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