LOANS AND ALLOWANCE FOR LOAN LOSSES (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,100,324	$ 3,026,222	$ 2,867,529
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,035,792	992,866
Loans	1,035,792	992,866	907,910
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,260,639	1,269,533
Loans	1,260,639	1,269,533	1,190,052
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	428,676	381,780
Loans	428,676	381,780	386,393
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	323,536	327,763
Loans	323,536	327,763	323,671
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	23,665	20,624
Loans	23,665	20,624	19,506
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	28,016	33,656
Loans	$ 28,016	$ 33,656	$ 39,997

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-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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