Quarterly report pursuant to Section 13 or 15(d)

Net Loss Per Common Share - Warrants and Options Excluded from Computation of Diluted Net Loss Per Share (Detail)

v3.8.0.1
Net Loss Per Common Share - Warrants and Options Excluded from Computation of Diluted Net Loss Per Share (Detail) - shares
shares in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Warrants    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Shares issuable 3,522 35
Stock Options    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Shares issuable 2,880 458