LEASES - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019	Feb. 01, 2019 ft²	Dec. 31, 2018
Lessee, Operating Lease, Discount Rate							9.16%
Operating Lease, Payments	$ 211,000	$ 234,000	$ 658,000	$ 674,000
Operating Lease, Weighted Average Remaining Lease Term	4 years 3 months 18 days		4 years 3 months 18 days		4 years 1 month 6 days
United States
Area of Land | ft²						20,821
Operating Leases, Rent Expense, Net			$ 34,000
Additional Operating Leases Rent Expense Net			30,000
Germany
Operating Leases, Rent Expense, Net			8,800
Additional Operating Leases Rent Expense Net			$ 2,900