PROPERTY, PLANT AND EQUIPMENT - Impairment Charges (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total Impairment	$ 5,200	$ 5,200	$ 143
Kingsville Dome project
Property, Plant and Equipment [Line Items]
Total Impairment		101	$ 143
Rosita Project
Property, Plant and Equipment [Line Items]
Total Impairment		1,161
Cebolleta/Juan Tafoya Property
Property, Plant and Equipment [Line Items]
Total Impairment		$ 3,938