DERIVATIVES AND HEDGING (Derivatives Not Designated as Hedging, by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 19,289	$ 5,038
Liability Derivatives, Fair Value	19,289	5,038
Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	19,289	5,038
Liability Derivatives, Fair Value	19,289	5,038
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	622,697	310,931
Liability Derivatives, Notional/Contract Amount	578,260	434,387
Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	20,951	3,339
Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	14,436	4,522
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	322,377	272,374
Liability Derivatives, Notional/Contract Amount	322,377	272,374
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	19,033	2,868
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Loans Receivable [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	608	282
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	14,143	2,868
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	106,436	20,229
Liability Derivatives, Notional/Contract Amount	77,133	17,763
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	1,406	273
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	45	187
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	193,884	18,328
Liability Derivatives, Notional/Contract Amount	178,750	144,250
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	512	198
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	$ 248	$ 1,467

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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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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