LOANS AND ALLOWANCE FOR LOAN LOSSES (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net unamortized loan origination costs	$ (612)	$ (66)
Loans	2,748,290	2,594,564	$ 2,592,009
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	852,851	802,494
Loans	852,851	802,494	797,036
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,131,883	1,050,780
Loans	1,131,883	1,050,780	1,054,307
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	369,155	333,639
Loans	369,155	333,639	324,422
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	328,328	329,907
Loans	328,328	329,907	333,095
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	18,123	17,332
Loans	18,123	17,332	17,416
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	47,950	60,412
Loans	$ 47,950	$ 60,412	$ 65,733

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 50
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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