LEASES - Summary of Supplemental Balance Sheet Information Related to Financing Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Lessee Lease Description [Line Items]
Property and equipment, at cost	$ 5,573	$ 5,627
Accumulated depreciation	(3,780)	(3,697)
Property and equipment, net	1,793	1,930
Finance lease liability	1,257	1,388
Other current liabilities
Lessee Lease Description [Line Items]
Finance lease liability	473	474
Other long-term liabilities
Lessee Lease Description [Line Items]
Finance lease liability	$ 784	$ 914