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, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	$ 15,196	$ 6,213	$ 15,196	$ 6,213	$ 14,858
Unpaid Principal Balance - with an allowance recorded	15,196	6,213	15,196	6,213	14,858
Related Allowance	1,704	2,015	1,704	2,015	2,007
Average Recorded Investment - with an allowance recorded	15,180	5,210	15,128	5,043	9,418
Interest Income Recognized - with an allowance recorded	40	25	66	52	106
Recorded Investment - without allowance recorded	4,884	5,024	4,884	5,024	5,396
Unpaid Principal Balance - without allowance recorded	6,841	6,323	6,841	6,323	7,756
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	4,778	9,931	4,971	8,499	6,970
Interest Income Recognized - without allowance recorded	15	20	30	37	76
Impaired Financing Receivable, Recorded Investment	20,080	11,237	20,080	11,237	20,254
Impaired financing receivable, unpaid principal balance	22,037	12,536	22,037	12,536	22,614
Impaired Financing Receivable, Average Recorded Investment	19,958	15,141	20,099	13,542	16,388
Impaired Financing Receivable, Interest Income, Accrual Method	55	45	96	89	182
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	3,026	3,067	3,026	3,067	3,019
Unpaid Principal Balance - with an allowance recorded	3,026	3,067	3,026	3,067	3,019
Related Allowance	468	497	468	497	483
Average Recorded Investment - with an allowance recorded	3,034	3,156	3,030	3,137	3,088
Interest Income Recognized - with an allowance recorded	29	25	55	52	106
Recorded Investment - without allowance recorded	1,425	1,859	1,425	1,859	1,329
Unpaid Principal Balance - without allowance recorded	1,786	2,347	1,786	2,347	1,800
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,327	3,071	1,310	2,547	2,057
Interest Income Recognized - without allowance recorded	5	4	7	4	9
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	12,049	99	12,049	99	11,443
Unpaid Principal Balance - with an allowance recorded	12,049	99	12,049	99	11,443
Related Allowance	1,116	29	1,116	29	1,373
Average Recorded Investment - with an allowance recorded	11,901	1,256	11,777	847	5,165
Interest Income Recognized - with an allowance recorded	11		11
Recorded Investment - without allowance recorded	1,067	2,241	1,067	2,241	1,874
Unpaid Principal Balance - without allowance recorded	1,303	2,765	1,303	2,765	2,369
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,251	2,655	1,477	2,475	2,214
Interest Income Recognized - without allowance recorded	4	23	14	25	51
Commercial
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	121	2,744	121	2,744	0
Unpaid Principal Balance - with an allowance recorded	121	2,744	121	2,744	0
Related Allowance	120	1,400	120	1,400	0
Average Recorded Investment - with an allowance recorded	41	239	21	633	762
Recorded Investment - without allowance recorded	1,946	717	1,946	717	2,028
Unpaid Principal Balance - without allowance recorded	3,120	814	3,120	814	3,209
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,962	3,978	1,993	3,281	2,507
Interest Income Recognized - without allowance recorded	2	(3)	5	8	16
Home Equity
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	303	0	303	299
Unpaid Principal Balance - with an allowance recorded	0	303	0	303	299
Related Allowance	0	89	0	89	86
Average Recorded Investment - with an allowance recorded	204	303	251	309	305
Recorded Investment - without allowance recorded	446	200	446	200	158
Unpaid Principal Balance - without allowance recorded	632	387	632	387	368
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	236	220	187	178	180
Interest Income Recognized - without allowance recorded	4	(4)	4
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				(11)	0
Recorded Investment - without allowance recorded	0	7	0	7	7
Unpaid Principal Balance - without allowance recorded	0	10	0	10	10
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	2	7	4	18	12
HPFC Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	0	0	0	97
Unpaid Principal Balance - with an allowance recorded	0	0	0	0	97
Related Allowance	0	0	0	0	65
Average Recorded Investment - with an allowance recorded		256	49	128	98
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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