Annual report pursuant to Section 13 and 15(d)

Financial Instruments - Additional Information (Detail)

v3.20.4
Financial Instruments - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Apr. 30, 2020
Apr. 30, 2018
Dec. 31, 2020
Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]        
Fair value of warrants     $ 200 $ (16)
Compensation Warrant [Member]        
Schedule Of Available For Sale Securities [Line Items]        
Warrants to purchase common stock 50,000      
Warrant exercise price $ 3.01      
Fair value of warrants     59  
Warrant exercisable date Dec. 31, 2021      
Performance Warrant [Member]        
Schedule Of Available For Sale Securities [Line Items]        
Warrants to purchase common stock 400,000      
Warrant exercise price $ 3.01      
Fair value of warrants     $ 43  
Warrant exercisable 133,333      
Warrant exercisable date Dec. 31, 2023      
Performance Warrant [Member] | First Installment [Member]        
Schedule Of Available For Sale Securities [Line Items]        
Warrant exercisable 133,333      
April 2018 Warrant [Member]        
Schedule Of Available For Sale Securities [Line Items]        
Warrants to purchase common stock   20,000    
Warrant exercise price   $ 11.73 $ 11.73 $ 11.73
Warrants maturity period   5 years 5 years 5 years
Fair value of warrants   $ 207