LOANS AND ALLOWANCE FOR LOAN LOSSES (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 3,157,762	$ 3,095,023	$ 3,042,442
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,064,212	1,070,374
Loans	1,064,212	1,070,374	1,017,442
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	1,299,860	1,243,397
Loans	1,299,860	1,243,397	1,258,474
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	444,830	421,108
Loans	444,830	421,108	390,982
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	306,226	312,779
Loans	306,226	312,779	323,969
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	24,377	25,772
Loans	24,377	25,772	20,733
HPFC Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	18,257	21,593
Loans	$ 18,257	$ 21,593	$ 30,842

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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