LEASES - Company's right-of-use asset and lease liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
LEASES
Operating lease right-of-use assets	$ 10,682	$ 10,695
Operating lease liabilities
Current portion included in current liabilities	7,196	7,252
Long-term portion included in non-current liabilities	3,711	4,248
Total Operating lease liabilities	$ 10,907	$ 11,500