ACQUISITIONS (Summary of Fair Value Adjustments to Amortized Cost Basis of Loans Acquired - Community) (Details) - Community Bank of Bergen County Merger $ in Thousands	Jan. 04, 2018 USD ($)
Business Acquisition [Line Items]
Gross amortized cost basis of acquired loans	$ 242,471
Fair value adjustment on general pooled loans	(3,737)
Credit fair value adjustment on purchased credit impaired loans	(2,664)
Fair value of acquired loans	$ 236,070

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Gross Amortized Cost Basis Amount

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- Definition

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Other-than-Temporary Impairment Charges, Credit Fair Value Increase (Decrease)

+ References

No definition available.

+ Details

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- Definition

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Other-than-Temporary Impairment Charges, General Pooled Loans, Credit Fair Value Increase (Decrease)

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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