Annual report pursuant to Section 13 and 15(d)

Stock Incentive Plan - Additional Information (Detail)

v3.20.4
Stock Incentive Plan - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Employee service share-based compensation, nonvested awards, compensation not yet recognized, stock options $ 0.2  
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition 1 year 9 months 18 days  
Expected term of award 7 years 7 months 6 days 6 years 8 months 12 days
Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term of award 10 years  
Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term of award 6 years  
Restricted Stock [Member] | Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 5 years  
Restricted Stock [Member] | Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 1 year  
Employee Stock Option [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based compensation arrangement by share-based payment award, number of shares authorized 8,000,000  
Share price $ 1.04  
Share-based compensation arrangement by share-based payment award, options, vested in period, fair value $ 0.4 $ 0.7
Employee Stock Option [Member] | Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 5 years  
Employee Stock Option [Member] | Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 4 years