STOCKHOLDERS' EQUITY - Restricted stock grants (Details) - Restricted stock awards [Member] - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
STOCKHOLDERS' EQUITY
Shares, Unvested at beginning of year	1,724,000	1,814,000
Shares, Grants	101,000	1,649,000
Shares, Vested	(1,749,000)	(1,739,000)
Shares, Unvested at end of year	76,000	1,724,000
Average Fair Value at Grant Date, Unvested at beginning of year (in dollars per share)	$ 0.83	$ 2.14
Average Fair Value at Grant Date, Grants (in dollars per share)	3.22	0.77
Average Fair Value at Grant Date, Vested (in dollars per share)	0.83	2.14
Average Fair Value at Grant Date, Unvested at end of year (in dollars per share)	$ 3.90	$ 0.83