Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss per Share (Detail)

v3.19.2
Summary of Significant Accounting Policies - Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss per Share (Detail) - shares
shares in Thousands
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]        
Anti-dilutive securities excluded from the computation of diluted loss per share 7,657 6,138 7,657 6,138
Common Stock Options [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive securities excluded from the computation of diluted loss per share 7,530 5,279 7,530 5,279
Incentive Awards [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive securities excluded from the computation of diluted loss per share 127 130 127 130
Common Stock Warrants [Member]        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Anti-dilutive securities excluded from the computation of diluted loss per share   729   729