Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Summary of Outstanding Warrants (Detail)

v3.20.2
Common Stock - Summary of Outstanding Warrants (Detail) - $ / shares
 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Series A-1 Warrants [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 108  
Exercise price per Share $ 5,280.0000  
Expiration Date 2020-10  
Warrants Issued In September 2017 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 411  
Exercise price per Share $ 699.2000  
Expiration Date 2023-03  
Warrants Issued in June 2018 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 114,100  
Exercise price per Share $ 80.0000 $ 80.00
Expiration Date 2023-06  
Warrants Issued in October 2018 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 31,215  
Exercise price per Share $ 62.8900 $ 62.89
Expiration Date 2023-10  
Warrants Issued in May 2019 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 60,000  
Exercise price per Share $ 90.0000  
Expiration Date 2025-05  
Warrants Issued in December 2019 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 1,060,718  
Exercise price per Share $ 6.6000  
Expiration Date 2024-12  
Warrants Issued in April 2020 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 182,461  
Exercise price per Share $ 7.2400  
Expiration Date 2025-04  
Warrants Issued in April 2020 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 28,125  
Exercise price per Share $ 7.3200  
Expiration Date 2025-04  
Warrants Issued in April 2020 [Member]    
Class of Warrant or Right [Line Items]    
Total Outstanding and Exercisable 25,270  
Exercise price per Share $ 7.5900  
Expiration Date 2025-04