LOANS AND ALLOWANCE FOR LOAN LOSSES (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net unamortized loan origination costs	$ (947)	$ (963)
Loans	2,867,529	2,782,439	$ 2,736,269
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	907,910	858,369
Loans	907,910	858,369	831,577
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,190,052	1,164,023
Loans	1,190,052	1,164,023	1,138,756
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	386,393	373,400
Loans	386,393	373,400	370,701
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	323,671	323,378
Loans	323,671	323,378	327,083
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	19,506	18,149
Loans	19,506	18,149	17,035
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	39,997	45,120
Loans	$ 39,997	$ 45,120	$ 51,117

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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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