Annual report pursuant to Section 13 and 15(d)

STOCK-BASED COMPENSATION - Additional Information (Details)

v3.20.4
STOCK-BASED COMPENSATION - Additional Information (Details)
12 Months Ended
Jun. 24, 2020
shares
Jun. 13, 2019
shares
Jan. 17, 2019
$ / shares
shares
Oct. 12, 2018
$ / shares
shares
May 31, 2018
shares
May 31, 2017
shares
Jun. 09, 2015
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Dec. 31, 2017
$ / shares
shares
Jan. 01, 2020
$ / shares
shares
Jan. 01, 2019
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Common Stock, Capital Shares Reserved for Future Issuance   1,682,000                    
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant               675,685        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross     118,750 167,430       653,750 411,930      
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price | $ / shares     $ 1.99 $ 2.61       $ 1.84 $ 2.33      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares               $ 1.42 $ 1.76      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value | $               $ 389,398 $ 715,587      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value | $ / shares               $ 6.62 $ 10.62      
Share-based Compensation Arrangement by Share-based Payment Award, Option, Nonvested, Weighted Average Exercise Price | $ / shares               1.44 1.82   $ 1.82 $ 4.14
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value | $ / shares               $ 1.90 $ 3.80      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares               209,354 203,523      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares                     361,743 186,895
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | $               $ 790,035        
Employee Service Share Based Compensation Nonvested Total Compensation In Current Year | $               424,673        
Employee Service Share Based Compensation Nonvested Total Compensation In Year Two | $               292,129        
Employee Service Share Based Compensation Nonvested Total Compensation In Year Three | $               $ 73,233        
Stock Option Activity [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross               653,750        
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price | $ / shares               $ 1.84 $ 2.33      
Non-vested restricted stock [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares               $ 0.00 $ 0.00      
Employee [Member] | Non-vested restricted stock [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Annual Forfeiture Rate Percentage               2.00% 2.00%      
Stock Incentive Plan 2015 [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized 700,000 700,000     120,000 120,000            
Common Stock, Capital Shares Reserved for Future Issuance             42,000          
Stockholders' Equity Note, Stock Split, Conversion Ratio             10          
Stock Incentive Plan 2015 [Member] | Non-vested restricted stock [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period                   3 years    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares                   $ 20.96    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease)                   8,000    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period                   46,000    
Stock Incentive Plan 2015 [Member] | Minimum [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               1 year        
Stock Incentive Plan 2015 [Member] | Maximum [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               4 years        
Stock Option Plan 2006 [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Common Stock, Capital Shares Reserved for Future Issuance               7,000        
Stock Option Plan 2006 [Member] | Minimum [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               1 year        
Stock Option Plan 2006 [Member] | Maximum [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               4 years