STOCK-BASED COMPENSATION - Compensation Expense (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
General and Administrative Expense [Member]        
STOCK-BASED COMPENSATION        
Stock compensation expense $ 10 $ 10 $ 40 $ 40