LEASES - Narrative (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Aug. 12, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Finance lease, lease liability	$ 3,051,000
Percentage of operating leases which are real estate leases	91.00%
Operating lease, ROU asset	$ 1,600,000		$ 1,900,000
Operating lease, liability	1,569,000		1,900,000
Accumulated depreciation	13,389,000		13,807,000
Annadale
Lessee, Lease, Description [Line Items]
Finance lease, ROU asset	3,000,000.0	$ 3,100,000
Finance lease, lease liability	$ 3,100,000	$ 3,100,000
Finance lease term		35 years
Assets Leased to Others | Marina
Lessee, Lease, Description [Line Items]
Carrying costs of property and equipment under operating lease, net of accumulated depreciation			68,900,000
Accumulated depreciation			$ 40,600,000
Minimum | Real Estate
Lessee, Lease, Description [Line Items]
Term of operating lease	5 years
Minimum | Property, Plant and Equipment
Lessee, Lease, Description [Line Items]
Term of operating lease	3 years
Maximum | Real Estate
Lessee, Lease, Description [Line Items]
Term of operating lease	15 years
Maximum | Property, Plant and Equipment
Lessee, Lease, Description [Line Items]
Term of operating lease	25 years
SJG
Lessee, Lease, Description [Line Items]
Finance lease, lease liability	$ 0
Percentage of operating leases which are real estate leases	68.00%
Operating lease, liability	$ 188,000