DERIVATIVES AND HEDGING (Derivatives Not Designated as Hedging, by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 25,246	$ 39,066
Liability Derivatives, Fair Value	23,877	39,204
Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	25,246	39,066
Liability Derivatives, Fair Value	23,877	39,204
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	880,249	671,564
Liability Derivatives, Notional/Contract Amount	520,385	728,271
Not Designated as Hedging Instrument [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	31,427	44,698
Not Designated as Hedging Instrument [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	18,003	24,082
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	458,118	451,760
Liability Derivatives, Notional/Contract Amount	458,118	451,760
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	25,241	39,057
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Loans Receivable [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	246	231
Not Designated as Hedging Instrument [Member] \| Interest rate swaps [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	17,918	22,327
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	139,668	140,390
Liability Derivatives, Notional/Contract Amount	62,267	72,511
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	2,937	5,221
Not Designated as Hedging Instrument [Member] \| Mortgage loan commitments [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	85	199
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional/Contract Amount	282,463	79,414
Liability Derivatives, Notional/Contract Amount	0	204,000
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member] \| Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	3,249	420
Not Designated as Hedging Instrument [Member] \| Forward Contracts [Member] \| Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	$ 0	$ 1,556

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
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-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
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-Topic 210
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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
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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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