LEASES - Supplemental Balance Sheet Information (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Operating leases
Operating lease right-of-use assets	$ 5,968,000	$ 6,605,000	$ 7,165,000
Operating lease liabilities - current	1,106,000	1,200,000	1,206,000
Operating lease liabilities - long-term	5,386,000	$ 5,940,000	6,494,000
Total operating lease liabilities	6,492,000		7,700,000
Finance leases
Property and equipment, at cost	8,663,000		8,582,000
Accumulated depreciation	(3,908,000)		(2,563,000)
Property and equipment, net	4,755,000		6,019,000
Finance lease liabilities - current	851,000		2,910,000
Finance lease liabilities - long-term	67,000		865,000
Total finance lease liabilities	$ 918,000		$ 3,775,000
Weighted average remaining lease term:
Operating leases	6 years		6 years 8 months 12 days
Finance leases	4 months 24 days		1 year 3 months 18 days
Weighted average discount rate:
Operating leases	5.04%		5.04%
Finance leases	4.69%		4.66%