LEASES - Lease balance sheet (Details) $ in Thousands	Dec. 31, 2021 USD ($)
LEASES
Right-of-use assets - current	$ 793
Right-of-use assets - non-current	$ 5,612
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent, Prepaid Expense and Other Assets, Current
Total right-of-use assets	$ 6,405
Lease liabilities - current	$ 943
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Liabilities, Current
Lease liabilities - non-current	$ 6,688
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent
Total operating lease liabilities	$ 7,631