LEASES - Lessee Accounting (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) contract	Dec. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Right-of-use asset	$ 2,652	$ 2,822
Lease liability	$ 2,674	$ 2,833
Operating lease, liability, extensible list	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent
Land | Yonkers, NY.
Lessee, Lease, Description [Line Items]
Number of contracts | contract	1
Renewal term option	21 years
Remaining term	24 years 9 months
Land | Great Neck, NY
Lessee, Lease, Description [Line Items]
Remaining term	16 years
Building | Great Neck, NY
Lessee, Lease, Description [Line Items]
Renewal term option	5 years