Annual report pursuant to Section 13 and 15(d)

Stock Incentive Plan - Stock Options Outstanding Additional Information (Detail)

v3.20.4
Stock Incentive Plan - Stock Options Outstanding Additional Information (Detail) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options 2,291,020 1,860,722
Weighted Average Contractual Life Remaining 4 years 3 months 18 days  
Weighted Average Exercise Price $ 3.23  
Exercisable Options 1,229,770  
Weighted Average Grant Date Fair Value $ 4.37  
Range of Exercise Prices From $1.00 to $3.00 [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Range of Exercise Prices, Lower Limit 1.00  
Range of Exercise Prices, Upper Limit $ 3.00  
Options 1,047,353  
Weighted Average Contractual Life Remaining 5 years 6 months  
Weighted Average Exercise Price $ 1.68  
Exercisable Options 276,853  
Weighted Average Grant Date Fair Value $ 2.48  
Range of Exercise Prices From $3.01 to $3.28 [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Range of Exercise Prices, Lower Limit 3.01  
Range of Exercise Prices, Upper Limit $ 3.28  
Options 533,000  
Weighted Average Contractual Life Remaining 4 years 9 months 18 days  
Weighted Average Exercise Price $ 3.25  
Exercisable Options 274,000  
Weighted Average Grant Date Fair Value $ 3.25  
Range of Exercise Prices From $3.29 to $4.63 [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Range of Exercise Prices, Lower Limit 3.29  
Range of Exercise Prices, Upper Limit $ 4.63  
Options 63,500  
Weighted Average Contractual Life Remaining 4 years 8 months 12 days  
Weighted Average Exercise Price $ 3.77  
Exercisable Options 31,750  
Weighted Average Grant Date Fair Value $ 3.77  
Range of Exercise Prices From $4.64 to $4.85 [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Range of Exercise Prices, Lower Limit 4.64  
Range of Exercise Prices, Upper Limit $ 4.85  
Options 398,542  
Weighted Average Contractual Life Remaining 2 years 8 months 12 days  
Weighted Average Exercise Price $ 4.85  
Exercisable Options 398,542  
Weighted Average Grant Date Fair Value $ 4.85  
Range of Exercise Prices From $4.86 to $6.65 [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Range of Exercise Prices, Lower Limit 4.86  
Range of Exercise Prices, Upper Limit $ 6.65  
Options 1,000  
Weighted Average Contractual Life Remaining 1 year  
Weighted Average Exercise Price $ 6.38  
Exercisable Options 1,000  
Weighted Average Grant Date Fair Value $ 6.38  
Range of Exercise Prices From $6.66 to $8.76 [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Range of Exercise Prices, Lower Limit 6.66  
Range of Exercise Prices, Upper Limit $ 8.76  
Options 247,625  
Weighted Average Contractual Life Remaining 7 months 6 days  
Weighted Average Exercise Price $ 7.00  
Exercisable Options 247,625  
Weighted Average Grant Date Fair Value $ 7.00