LOANS AND ALLOWANCE FOR LOAN LOSSES (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net unamortized loan origination (costs) fees	$ 248	$ 66
Loans	2,645,139	2,594,564	$ 2,492,634
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	819,639	802,494
Loans	819,639	802,494	811,974
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,096,475	1,050,780
Loans	1,096,475	1,050,780	952,481
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	333,607	333,639
Loans	333,607	333,639	292,064
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	322,826	329,907
Loans	322,826	329,907	344,497
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	16,669	17,332
Loans	16,669	17,332	17,189
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	55,923	60,412
Loans	$ 55,923	$ 60,412	$ 74,429

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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.

+ References

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