LEASES - Lease Term and Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Leases [Abstract]
Weighted-average remaining lease term (in years)	8 years 6 months 25 days		8 years 6 months 25 days		9 years 3 months 3 days
Weighted-average discount rate	3.15%		3.15%		3.15%
Operating lease cost	$ 324	$ 344	$ 966	$ 988
Variable lease cost	43	59	179	177
Total lease cost	$ 367	$ 403	$ 1,145	$ 1,165