Quarterly report pursuant to Section 13 or 15(d)

STOCK-BASED COMPENSATION - Additional Information (Details)

v3.19.2
STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($)
1 Months Ended 6 Months Ended 12 Months Ended
Oct. 12, 2018
Jun. 30, 2019
Jan. 17, 2019
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Dec. 31, 2017
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 167,430   118,750 321,930 8,000    
Employee Service Share Based Compensation Nonvested Total Compensation In Current Year       $ 272,106      
Employee Service Share Based Compensation Nonvested Total Compensation In Year Two       262,553      
Employee Service Share Based Compensation Nonvested Total Compensation In Year Three       147,749      
Employee Service Share Based Compensation Nonvested Total Compensation in Year Four       2,685      
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized   $ 685,093   $ 685,093      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value       $ 20.18      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price   $ 1.91   $ 1.91      
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price $ 2.61   $ 1.99        
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   167,430   154,500      
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price       $ 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       $ 0      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period       0      
Non-vested restricted stock [Member] | 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, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value       $ 20.96      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period             46,000
Employee [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Annual Forfeiture Rate Percentage       2.00%      
Director [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Annual Forfeiture Rate Percentage       0.00%   0.00%