LEASES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Lessee, Lease, Description [Line Items]
Operating lease, weighted average remaining lease term	12 years 1 month 6 days
Operating lease, weighted average discount rate	3.37%
Operating leases, rent expense	$ 200
Finance lease, weighted average remaining lease term	13 years 8 months 12 days
Finance lease, weighted average discount rate	3.51%
Director
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 24	$ 12
1365 New Scotland Road, Slingerlands, New York | Director
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	12	$ 12
Operating lease, monthly rent expense	4
2 Rush Street, Schenectady, New York | Director
Lessee, Lease, Description [Line Items]
Operating lease, monthly rent expense	$ 8