LOANS AND ALLOWANCE FOR LOAN LOSSES (Summary of Impaired Loan Balances and Associated Allowance by Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	$ 4,706	$ 4,322	$ 4,706	$ 4,322	$ 4,476
Unpaid Principal Balance - with an allowance recorded	4,706	4,322	4,706	4,322	4,476
Related Allowance	1,183	834	1,183	834	824
Average Recorded Investment - with an allowance recorded	4,559	5,802	4,532	6,961	5,921
Interest Income Recognized - with an allowance recorded	31	49	62	80	138
Recorded Investment - without allowance recorded	1,737	8,269	1,737	8,269	2,450
Unpaid Principal Balance - without allowance recorded	2,222	10,126	2,222	10,126	3,001
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,794	6,106	2,013	5,507	5,368
Interest Income Recognized - without allowance recorded	13	4	28	18	55
Impaired Financing Receivable, Recorded Investment	6,443	12,591	6,443	12,591	6,926
Impaired financing receivable, unpaid principal balance	6,928	14,448	6,928	14,448	7,477
Impaired Financing Receivable, Average Recorded Investment	6,353	11,908	6,545	12,468	11,289
Impaired Financing Receivable, Interest Income, Accrual Method	44	53	90	98	193
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	3,286	3,506	3,286	3,506	3,471
Unpaid Principal Balance - with an allowance recorded	3,286	3,506	3,286	3,506	3,471
Related Allowance	524	585	524	585	586
Average Recorded Investment - with an allowance recorded	3,370	3,525	3,404	3,636	3,591
Interest Income Recognized - with an allowance recorded	26	39	56	69	127
Recorded Investment - without allowance recorded	1,186	1,894	1,186	1,894	1,291
Unpaid Principal Balance - without allowance recorded	1,310	2,200	1,310	2,200	1,415
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,234	1,704	1,253	1,574	1,524
Interest Income Recognized - without allowance recorded	7	7	17	14	34
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	131	351	131	351	131
Unpaid Principal Balance - with an allowance recorded	131	351	131	351	131
Related Allowance	27	23	27	23	23
Average Recorded Investment - with an allowance recorded	131	1,971	131	3,121	1,969
Interest Income Recognized - with an allowance recorded	5	10	6	11	11
Recorded Investment - without allowance recorded	278	4,742	278	4,742	799
Unpaid Principal Balance - without allowance recorded	437	5,080	437	5,080	975
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	278	2,556	452	1,963	2,269
Interest Income Recognized - without allowance recorded	4	(3)	7		13
Commercial
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	461	0	461	0	556
Unpaid Principal Balance - with an allowance recorded	461	0	461	0	556
Related Allowance	322	0	322	0	53
Average Recorded Investment - with an allowance recorded	230		339		111
Recorded Investment - without allowance recorded	214	1,611	214	1,611	230
Unpaid Principal Balance - without allowance recorded	278	2,785	278	2,785	293
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	219	1,663	222	1,705	1,379
Interest Income Recognized - without allowance recorded	2	2	4	4	8
Home Equity
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	828	465	828	465	318
Unpaid Principal Balance - with an allowance recorded	828	465	828	465	318
Related Allowance	310	226	310	226	162
Average Recorded Investment - with an allowance recorded	828	306	658	204	250
Recorded Investment - without allowance recorded	59	22	59	22	124
Unpaid Principal Balance - without allowance recorded	197	61	197	61	305
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	63	183	84	265	195
Interest Income Recognized - without allowance recorded		(2)
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	6
Unpaid Principal Balance - without allowance recorded	0	0	0	0	13
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded			2		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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