Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Summary of Outstanding Warrants (Detail)

v3.19.3
Common Stock - Summary of Outstanding Warrants (Detail) - $ / shares
 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Jun. 19, 2018
Class of Warrant or Right [Line Items]      
Exercise price per Share     $ 4.00
Series A-1 Warrants [Member]      
Class of Warrant or Right [Line Items]      
Total Outstanding and Exercisable 2,175    
Exercise price per Share $ 264.0000    
Expiration Date 2020-10    
Warrants Issued In September 2017 [Member]      
Class of Warrant or Right [Line Items]      
Total Outstanding and Exercisable 8,224    
Exercise price per Share $ 34.9600    
Expiration Date 2023-03    
Warrants Issued In June 2018 [Member]      
Class of Warrant or Right [Line Items]      
Total Outstanding and Exercisable 2,282,000    
Exercise price per Share $ 4.0000 $ 4.00  
Expiration Date 2023-06    
Warrants Issued in October 2018 [Member]      
Class of Warrant or Right [Line Items]      
Total Outstanding and Exercisable 624,313    
Exercise price per Share $ 3.1445    
Expiration Date 2023-10    
Warrants Issued in May 2019 [Member]      
Class of Warrant or Right [Line Items]      
Total Outstanding and Exercisable 1,200,000    
Exercise price per Share $ 4.5000    
Expiration Date 2025-05