REVENUE FROM CONTRACTS WITH CUSTOMERS - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 7,370	$ 6,636
Products and services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	3,757	3,287
Products and services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	3,613	3,349
Trust management fees
Disaggregation of Revenue [Line Items]
Revenue	3,403	3,175
Financial services fees
Disaggregation of Revenue [Line Items]
Revenue	351	491
Interchange fees
Disaggregation of Revenue [Line Items]
Revenue	1,973	1,712
Customer deposit fees
Disaggregation of Revenue [Line Items]
Revenue	1,372	1,049
Other customer service fees
Disaggregation of Revenue [Line Items]
Revenue	$ 271	$ 209