DERIVATIVES AND HEDGING (Derivatives Not Designated as Hedging, by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 43,506	$ 15,242
Liability Derivatives, Fair Value	43,653	15,242
Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	43,506	15,242
Liability Derivatives, Fair Value	43,653	15,242
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	754,325	493,607
Liability Derivatives, Notional/Contract Amount	757,909	677,132
Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	53,964	16,090
Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	25,422	11,420
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	419,497	371,957
Liability Derivatives, Notional/Contract Amount	419,497	371,957
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	43,491	14,982
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Loans Receivable [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	1,500	347
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	23,912	10,746
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	224,834	50,755
Liability Derivatives, Notional/Contract Amount	79,412	65,855
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	8,454	791
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	516	190
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	109,994	70,895
Liability Derivatives, Notional/Contract Amount	259,000	239,320
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	2,019	317
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	$ 994	$ 484

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=121590274&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=121590274&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=121590274&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
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Balance Type:	debit
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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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- Details

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