Quarterly report pursuant to Section 13 or 15(d)

Net Income (Loss) Per Share of Common Stock - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted Average Shares Outstanding (Detail)

v3.19.2
Net Income (Loss) Per Share of Common Stock - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted Average Shares Outstanding (Detail) - shares
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Potentially antidilutive securities outstanding excluded from the computation of diluted weighted average shares 42,917,318 38,944,668 42,917,948 38,944,668
Employee Stock Options [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Potentially antidilutive securities outstanding excluded from the computation of diluted weighted average shares 12,364,994 7,266,054 12,316,624 7,266,054
Warrants [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Potentially antidilutive securities outstanding excluded from the computation of diluted weighted average shares 30,572,324 31,678,614 30,572,324 31,678,614