DERIVATIVES - Amounts Recorded in Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (8)	$ (17)
Debt Securities
Derivative [Line Items]
Carrying amount of hedged assets(2)	9,557	7,253
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	(97)	60
Debt Securities \| Closed Portfolios
Derivative [Line Items]
Carrying amount of hedged assets(2)	6,400	5,900
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	(75)	39
Amount of hedged item	4,700	4,000
Long-term borrowed funds
Derivative [Line Items]
Carrying amount of hedged liabilities	491	483
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (8)	$ (17)

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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Amount of asset hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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-Section 50
-Paragraph 4EE
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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