ACCRUED LIABILITIES - Accrued Liabilities on the Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
ACCRUED LIABILITIES.
Royalties payable	$ 1,151	$ 1,166
Other Accrued Liabilities	1,218	1,104
Total accrued Liabilities	$ 2,369	$ 2,270