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, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	$ 14,803	$ 4,739	$ 14,803	$ 4,739	$ 5,475
Unpaid Principal Balance - with an allowance recorded	14,803	4,772	14,803	4,772	5,507
Related Allowance	1,957	1,184	1,957	1,184	1,369
Average Recorded Investment - with an allowance recorded	12,752	4,834	7,620	4,920	9,857
Interest Income Recognized - with an allowance recorded	56	60	81	88	114
Recorded Investment - without allowance recorded	5,879	5,811	5,879	5,811	9,760
Unpaid Principal Balance - without allowance recorded	9,474	6,915	9,474	6,915	12,942
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	5,295	5,699	7,424	5,316	6,695
Interest Income Recognized - without allowance recorded	36	26	56	59	90
Impaired Financing Receivable, Recorded Investment	20,682	10,550	20,682	10,550	15,235
Impaired financing receivable, unpaid principal balance	24,277	11,687	24,277	11,687	18,449
Impaired Financing Receivable, Average Recorded Investment	18,047	10,533	15,044	10,236	16,552
Impaired Financing Receivable, Interest Income, Accrual Method	92	86	137	147	204
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	3,041	3,581	3,041	3,581	3,191
Unpaid Principal Balance - with an allowance recorded	3,041	3,581	3,041	3,581	3,191
Related Allowance	511	645	511	645	544
Average Recorded Investment - with an allowance recorded	3,050	4,409	3,108	4,168	6,064
Interest Income Recognized - with an allowance recorded	56	55	81	82	112
Recorded Investment - without allowance recorded	1,510	1,619	1,510	1,619	2,835
Unpaid Principal Balance - without allowance recorded	1,996	2,118	1,996	2,118	4,353
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,731	1,774	2,275	1,607	2,175
Interest Income Recognized - without allowance recorded	7	4	7	6	8
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	11,354	468	11,354	468	1,825
Unpaid Principal Balance - with an allowance recorded	11,354	501	11,354	501	1,857
Related Allowance	1,284	280	1,284	280	644
Average Recorded Investment - with an allowance recorded	7,582	86	3,092	259	1,753
Recorded Investment - without allowance recorded	1,932	3,269	1,932	3,269	2,785
Unpaid Principal Balance - without allowance recorded	2,427	3,430	2,427	3,430	3,426
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	2,015	3,102	2,322	2,735	2,719
Interest Income Recognized - without allowance recorded	33	18	37	45	65
Commercial
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	247	0	247	156
Unpaid Principal Balance - with an allowance recorded	0	247	0	247	156
Related Allowance	0	92	0	92	92
Average Recorded Investment - with an allowance recorded	1,782	199	1,016	218	945
Interest Income Recognized - with an allowance recorded		5		6	2
Recorded Investment - without allowance recorded	2,243	703	2,243	703	3,781
Unpaid Principal Balance - without allowance recorded	4,667	876	4,667	876	4,325
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	1,354	503	2,639	567	1,412
Interest Income Recognized - without allowance recorded	(11)	4	12	8	17
Home Equity
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	302	303	302	303	303
Unpaid Principal Balance - with an allowance recorded	302	303	302	303	303
Related Allowance	88	89	88	89	89
Average Recorded Investment - with an allowance recorded	303		307	135	900
Recorded Investment - without allowance recorded	187	203	187	203	285
Unpaid Principal Balance - without allowance recorded	374	454	374	454	688
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	188	303	181	390	369
Interest Income Recognized - without allowance recorded	3
Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	0	140	0	140	0
Unpaid Principal Balance - with an allowance recorded	0	140	0	140	0
Related Allowance	0	78	0	78	0
Average Recorded Investment - with an allowance recorded		140		140	195
Recorded Investment - without allowance recorded	7	17	7	17	74
Unpaid Principal Balance - without allowance recorded	10	37	10	37	150
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0	0	0
Average Recorded Investment - without allowance recorded	7	17	7	17	20
Interest Income Recognized - without allowance recorded	4
HPFC Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment - with an allowance recorded	106	0	106	0	0
Unpaid Principal Balance - with an allowance recorded	106	0	106	0	0
Related Allowance	74	0	74	0	0
Average Recorded Investment - with an allowance recorded	35		97		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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