LOANS AND ALLOWANCE FOR LOAN LOSSES (Summary of Impaired Loan Balances and Associated Allowance by Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	$ 2,836	$ 3,227	$ 2,836	$ 3,227	$ 2,841
Unpaid Principal Balance - with an allowance recorded	2,836	3,227	2,836	3,227	2,841
Related Allowance	494	738	494	738	463
Average Recorded Investment - with an allowance recorded	2,793	4,115	2,773	4,205	3,933
Interest Income Recognized - with an allowance recorded	35	31	85	93	121
Recorded Investment - without allowance recorded	1,288	2,290	1,288	2,290	1,637
Unpaid Principal Balance - without allowance recorded	1,826	3,414	1,826	3,414	2,426
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,350	1,960	1,507	2,081	1,993
Interest Income Recognized - without allowance recorded	6	15	17	43	41
Impaired Financing Receivable, Recorded Investment	4,124	5,517	4,124	5,517	4,478
Impaired financing receivable, unpaid principal balance	4,662	6,641	4,662	6,641	5,267
Impaired Financing Receivable, Average Recorded Investment	4,143	6,075	4,280	6,286	5,926
Impaired Financing Receivable, Interest Income, Accrual Method	41	46	102	136	162
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	2,394	2,337	2,394	2,337	2,395
Unpaid Principal Balance - with an allowance recorded	2,394	2,337	2,394	2,337	2,395
Related Allowance	371	337	371	337	364
Average Recorded Investment - with an allowance recorded	2,349	3,026	2,328	3,137	2,989
Interest Income Recognized - with an allowance recorded	33	28	79	84	110
Recorded Investment - without allowance recorded	734	1,543	734	1,543	989
Unpaid Principal Balance - without allowance recorded	858	2,007	858	2,007	1,116
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	791	1,337	909	1,325	1,258
Interest Income Recognized - without allowance recorded	2	11	4	28	21
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	126	130	126	130	128
Unpaid Principal Balance - with an allowance recorded	126	130	126	130	128
Related Allowance	36	29	36	29	30
Average Recorded Investment - with an allowance recorded	127	130	127	130	130
Interest Income Recognized - with an allowance recorded	2	3	6	9	11
Recorded Investment - without allowance recorded	334	276	334	276	274
Unpaid Principal Balance - without allowance recorded	548	435	548	435	433
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	334	278	304	408	381
Interest Income Recognized - without allowance recorded	3	3	9	10	13
Commercial
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	442	0	442	0
Unpaid Principal Balance - with an allowance recorded	0	442	0	442	0
Related Allowance	0	303	0	303	0
Average Recorded Investment - with an allowance recorded		301		365	292
Recorded Investment - without allowance recorded	171	204	171	204	319
Unpaid Principal Balance - without allowance recorded	233	267	233	267	685
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	175	214	242	218	238
Interest Income Recognized - without allowance recorded	1	1	4	5	7
SBA PPP Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	0	0	0	0
Unpaid Principal Balance - with an allowance recorded	0	0	0	0	0
Related Allowance	0	0	0	0	0
Average Recorded Investment - with an allowance recorded					0
Recorded Investment - without allowance recorded	0	0	0	0	0
Unpaid Principal Balance - without allowance recorded	0	0	0	0	0
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded					0
Interest Income Recognized - without allowance recorded					0
Home Equity
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	316	318	316	318	318
Unpaid Principal Balance - with an allowance recorded	316	318	316	318	318
Related Allowance	87	69	87	69	69
Average Recorded Investment - with an allowance recorded	317	658	318	573	522
Recorded Investment - without allowance recorded	49	267	49	267	55
Unpaid Principal Balance - without allowance recorded	187	705	187	705	192
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	50	131	52	130	115
Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	0	0	0	0
Unpaid Principal Balance - with an allowance recorded	0	0	0	0	0
Related Allowance	0	0	0	0	0
Average Recorded Investment - with an allowance recorded					0
Recorded Investment - without allowance recorded	0	0	0	0	0
Unpaid Principal Balance - without allowance recorded	0	0	0	0	0
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded					1
HPFC Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	0	0	0	0
Unpaid Principal Balance - with an allowance recorded	0	0	0	0	0
Related Allowance	0	0	0	0	0
Average Recorded Investment - with an allowance recorded					0
Recorded Investment - without allowance recorded	0	0	0	0	0
Unpaid Principal Balance - without allowance recorded	0	0	0	0	0
Impaired Financing Receivable With No Related Allowance Related Allowance	$ 0	$ 0	$ 0	$ 0
Average Recorded Investment - without allowance recorded					$ 0

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