STOCKHOLDERS' EQUITY - Restricted stock grants (Details) - Restricted stock awards [Member]	6 Months Ended
	Jun. 30, 2021 $ / shares shares
STOCKHOLDERS' EQUITY
Shares, Unvested at beginning of year | shares	1,724,000
Shares, Grants | shares	62,000
Shares, Vested | shares	(1,730,000)
Shares, Forfeited/cancelled/expired | shares	0
Shares, Unvested at end of year | shares	56,000
Average Fair Value at Grant Date, Unvested at beginning of year (in dollars per share) | $ / shares	$ 0.83
Average Fair Value at Grant Date, Grants (in dollars per share) | $ / shares	2.00
Average Fair Value at Grant Date, Vested (in dollars per share) | $ / shares	0.82
Average Fair Value at Grant Date, Forfeited/cancelled/expired (in dollars per share) | $ / shares	0
Average Fair Value at Grant Date, Unvested at end of year (in dollars per share) | $ / shares	$ 2.45