SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Net Loss (income) Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net income (loss) attributable to common shareholders
Net income (loss) from continuing operations	$ 3,686	$ (1,646)	$ (10,391)	$ (14,601)
Net income (loss) from discontinued operations	0	(6)	0	37
Net income (loss)	$ 3,686	$ (1,652)	$ (10,391)	$ (14,564)
Weighted-average common shares outstanding:
Weighted-average common shares outstanding: basic	73,061,790	61,321,424	65,841,840	61,321,424
Weighted-average common shares outstanding: diluted	73,061,790	61,321,424	65,841,840	61,321,424
Income (loss) per common share – Basic and diluted
Income (loss) from continuing operations, per basic share (in usd per share)	$ 0.05	$ (0.03)	$ (0.16)	$ (0.24)
Income (loss) from continuing operations, per diluted share (in usd per share)	0.05	(0.03)	(0.16)	(0.24)
Income (loss) from continuing operations, per basic (in usd per share)	0	0	0	0
Income (loss) from continuing operations, per diluted (in usd per share)	0	0	0	0
Net income (loss) per common share - basic (in usd per share)	0.05	(0.03)	(0.16)	(0.24)
Net income (loss) per common share - diluted (in usd per share)	$ 0.05	$ (0.03)	$ (0.16)	$ (0.24)