Annual report pursuant to Section 13 and 15(d)

Warrants - Additional Information (Detail)

v3.21.1
Warrants - Additional Information (Detail)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 08, 2020
shares
Nov. 20, 2020
day
$ / shares
shares
Oct. 28, 2020
$ / shares
shares
Dec. 04, 2019
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Dec. 02, 2020
$ / shares
Nov. 02, 2020
shares
Aug. 24, 2020
$ / shares
Jun. 08, 2019
shares
Jan. 26, 2019
$ / shares
shares
Jan. 09, 2019
$ / shares
shares
Class of Warrant or Right [Line Items]                        
Common stock, par value (usd per share) | $ / shares         $ 0.0001 $ 0.0001 $ 0.0001   $ 0.0001      
Number of shares issued in transaction 50,000   1,600,000 5,000                
Change in fair value of warrant liability | $         $ 167 $ 70            
Warrants to purchase common stock, issued (shares)     94,000         94,092       31,000
Exercise price of warrant (usd per share) | $ / shares     $ 2.42   $ 104.18             $ 7.43
Warrants Issued (shares)     94,000   94,000 66,000            
Warrant Exchange                        
Class of Warrant or Right [Line Items]                        
Number of shares called by each warrant   0.2                    
Common stock, par value (usd per share) | $ / shares   $ 0.0001                    
Trading days of no stock issuance | day   5                    
Number of shares issued in transaction   11,000                    
Change in fair value of warrant liability | $         $ 2              
2017 Offering                        
Class of Warrant or Right [Line Items]                        
Warrants to purchase common stock, issued (shares)                   123,000    
H.C. Wainwright                        
Class of Warrant or Right [Line Items]                        
Warrants to purchase common stock, issued (shares)                     36,000 445,000
Exercise price of warrant (usd per share) | $ / shares                     $ 7.59 $ 6.75