LOANS AND ALLOWANCE FOR LOAN LOSSES (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,042,442	$ 3,026,222	$ 2,789,148
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,017,442	992,866
Loans	1,017,442	992,866	860,533
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,258,474	1,269,533
Loans	1,258,474	1,269,533	1,169,533
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	390,982	381,780
Loans	390,982	381,780	378,015
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	323,969	327,763
Loans	323,969	327,763	320,642
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	20,733	20,624
Loans	20,733	20,624	18,011
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	30,842	33,656
Loans	$ 30,842	$ 33,656	$ 42,414

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- Definition

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.

+ References

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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