STOCKHOLDERS' EQUITY - Share-Based Compensation (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
STOCKHOLDERS' EQUITY
Stock-based compensation (income)/expense	$ (41,648)	$ 434,367	$ 62,284	$ 926,698
Granted			983,000
Stock-based compensation options, expiration period			5 years
Vesting period			1 year
Fair value of awards, grant date			$ 594,080
Unrecognized compensation expense related to unvested Employee Awards	$ 393,391		$ 393,391
Recognition period related to unvested Employee Awards			11 months
Number of Shares
Outstanding, beginning of period			7,266,420
Granted			983,000
Exercised			(333,620)
Forfeited or expired			(1,006,930)
Outstanding, end of period	6,908,870		6,908,870		7,266,420
Exercisable, end of period	5,613,490		5,613,490
Weighted-average Exercise Price per Share
Outstanding, beginning of period			$ 1.03
Granted			0.91
Exercised			0.54
Forfeited or expired			3.95
Outstanding, end of period	$ 1.07		1.07		$ 1.03
Exercisable, end of period	$ 1.16		$ 1.16
Weighted-average Remaining Contractual Term (in years)
Outstanding contractual term (in years)			5 years 3 months 18 days		5 years 6 months
Exercisable, end of period			5 years 3 months 18 days
Aggregate Intrinsic Value
Outstanding, end of period	$ 303,000		$ 303,000		$ 167,000
Exercisable, end of period	$ 153,000		$ 153,000