LOANS AND ALLOWANCE FOR CREDIT LOSSES ON LOANS (Summary of Impaired Loan Balances and Associated Allowance by Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2021
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	$ 2,836
Unpaid Principal Balance - with an allowance recorded	2,836
Related Allowance	494
Average Recorded Investment - with an allowance recorded	2,793	$ 2,773
Interest Income Recognized - with an allowance recorded	35	85
Recorded Investment - without allowance recorded	1,288
Unpaid Principal Balance - without allowance recorded	1,826
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Average Recorded Investment - without allowance recorded	1,350	1,507
Interest Income Recognized - without allowance recorded	6	17
Impaired Financing Receivable, Recorded Investment	4,124
Impaired financing receivable, unpaid principal balance	4,662
Impaired Financing Receivable, Average Recorded Investment	4,143	4,280
Impaired Financing Receivable, Interest Income, Accrual Method	41	102
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	2,394
Unpaid Principal Balance - with an allowance recorded	2,394
Related Allowance	371
Average Recorded Investment - with an allowance recorded	2,349	2,328
Interest Income Recognized - with an allowance recorded	33	79
Recorded Investment - without allowance recorded	734
Unpaid Principal Balance - without allowance recorded	858
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Average Recorded Investment - without allowance recorded	791	909
Interest Income Recognized - without allowance recorded	2	4
Commercial Real Estate(1)
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	126
Unpaid Principal Balance - with an allowance recorded	126
Related Allowance	36
Average Recorded Investment - with an allowance recorded	127	127
Interest Income Recognized - with an allowance recorded	2	6
Recorded Investment - without allowance recorded	334
Unpaid Principal Balance - without allowance recorded	548
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Average Recorded Investment - without allowance recorded	334	304
Interest Income Recognized - without allowance recorded	3	9
Commercial
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0
Unpaid Principal Balance - with an allowance recorded	0
Related Allowance	0
Recorded Investment - without allowance recorded	171
Unpaid Principal Balance - without allowance recorded	233
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Average Recorded Investment - without allowance recorded	175	242
Interest Income Recognized - without allowance recorded	1	4
SBA PPP Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0
Unpaid Principal Balance - with an allowance recorded	0
Related Allowance	0
Recorded Investment - without allowance recorded	0
Unpaid Principal Balance - without allowance recorded	0
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Home Equity
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	316
Unpaid Principal Balance - with an allowance recorded	316
Related Allowance	87
Average Recorded Investment - with an allowance recorded	317	318
Recorded Investment - without allowance recorded	49
Unpaid Principal Balance - without allowance recorded	187
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Average Recorded Investment - without allowance recorded	50	$ 52
Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0
Unpaid Principal Balance - with an allowance recorded	0
Related Allowance	0
Recorded Investment - without allowance recorded	0
Unpaid Principal Balance - without allowance recorded	0
Impaired Financing Receivable With No Related Allowance Related Allowance	$ 0

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