v3.19.2

Net and Comprehensive Loss Per Share - Schedule of Weighted Average Common Stock Equivalents Excluded from Calculation of Basic and Diluted Net and Comprehensive Loss per Share (Detail) - Weighted Average [Member] - shares	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share	6,771,807	3,285,429
Unvested Restricted Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share		53,223
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total amount of anti-dilutive securities excluded from computation of earnings per share	317,562	317,562

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://fasb.org/us-gaap/role/ref/legacyRef
-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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