DERIVATIVES - Derivative Financial Instruments, Average Remaining Maturity and the Weighted-Average Interest Rates being Paid and Received (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative, Notional Amount	$ 18,498,760	$ 11,875,690
Average Maturity (years)	1 year 10 months 24 days
Fair Value	$ (76)
Interest Rate Swap \| Derivative Financial Instruments Receive Fixed Pay Variable
Derivative [Line Items]
Derivative, Notional Amount	$ 2,348,651
Average Maturity (years)	5 years 9 months 18 days
Fair Value	$ 103,083
Interest Rate Swap \| Derivative Financial Instruments Receive Variable Pay Fixed
Derivative [Line Items]
Derivative, Notional Amount	$ 2,348,651
Average Maturity (years)	5 years 9 months 18 days
Fair Value	$ (103,159)
Foreign Exchange \| Derivative Financial Instruments Receive Fixed Pay Variable
Derivative [Line Items]
Derivative, Notional Amount	$ 6,900,729
Average Maturity (years)	7 months 6 days
Fair Value	$ 14,863
Foreign Exchange \| Derivative Financial Instruments Receive Variable Pay Fixed
Derivative [Line Items]
Derivative, Notional Amount	$ 6,900,729
Average Maturity (years)	7 months 6 days
Fair Value	$ (14,863)

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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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.

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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

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=125515794&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=125515794&loc=SL5579245-113959

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