OPERATING LEASES - Lease, Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
OPERATING LEASES
Operating lease costs	$ 1,382	$ 1,219
Cash paid for amounts included in the measurement of lease liabilities	$ 1,289	$ 1,329
Weighted average remaining lease term (in years)	9 years 6 months	10 years 6 months
Weighted average discount rate	12.70%	12.70%