DERIVATIVES (Derivatives Designated in Hedge Relationships) (Details) - Designated as hedging instrument - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Notional Amount	$ 13,770,000	$ 14,020,000
Asset, Total	250,426	29,031
Liability, Total	$ 88,512	$ 68,337
Weighted Average Receive Rate	1.27%	1.17%
Weighted Average Pay Rate	0.39%	1.29%
Weighted Average
Derivative [Line Items]
Weighted Average Life (Years)	1 year 9 months 18 days	1 year 11 months 26 days
Cash flow hedges \| Pay fixed — receive variable interest rate swaps
Derivative [Line Items]
Notional Amount	$ 2,750,000	$ 2,650,000
Asset, Cash flow hedges	0	2,807
Liability, Cash flow hedges	$ 88,512	$ 39,128
Weighted Average Receive Rate	0.23%	1.85%
Weighted Average Pay Rate	1.49%	1.91%
Cash flow hedges \| Pay fixed — receive variable interest rate swaps \| Weighted Average
Derivative [Line Items]
Weighted Average Life (Years)	2 years 2 months 8 days	1 year 10 months 9 days
Cash flow hedges \| Pay variable - receive fixed interest rate swaps
Derivative [Line Items]
Notional Amount	$ 7,070,000	$ 7,570,000
Asset, Cash flow hedges	194,232	7,462
Liability, Cash flow hedges	$ 0	$ 29,209
Weighted Average Receive Rate	1.41%	1.43%
Weighted Average Pay Rate	0.18%	1.73%
Cash flow hedges \| Pay variable - receive fixed interest rate swaps \| Weighted Average
Derivative [Line Items]
Weighted Average Life (Years)	2 years 2 months 8 days	2 years 4 months 20 days
Cash flow hedges \| Interest rate floor
Derivative [Line Items]
Notional Amount	$ 3,950,000	$ 3,800,000
Asset, Cash flow hedges	56,194	18,762
Liability, Cash flow hedges	$ 0	$ 0
Weighted Average Receive Rate	1.75%	0.19%
Weighted Average Pay Rate	0.00%	0.00%
Cash flow hedges \| Interest rate floor \| Weighted Average
Derivative [Line Items]
Weighted Average Life (Years)	10 months 2 days	1 year 3 months 10 days

Average fixed interest rate related to the group of interest rate derivatives.

No definition available.

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Average variable interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

+ References

No definition available.

+ Details

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- Definition

Aggregate fair value of all derivative liabilities designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

+ 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.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: 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 2: 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

+ Details

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- Definition

Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

+ References

+ Details

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