DERIVATIVES - Schedule of Fair Value Hedges (Details) - Hedge of interest rate risk - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Interest Income, Loans Held for Sale
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Item	$ 0	$ 0	$ (13)
Derivative	0	0	13
Amounts related to interest settlements on derivatives	0	0	0
Total net interest income recognized on fair value hedges	0	0	0
Interest Income, Investment Securities
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Item	(142)	50	(29)
Derivative	147	(48)	29
Amounts related to interest settlements on derivatives	107	10	(3)
Total net interest income recognized on fair value hedges	112	12	(3)
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Item	(8)	(10)	68
Derivative	8	10	(69)
Amounts related to interest settlements on derivatives	(14)	(16)	12
Total net interest income recognized on fair value hedges	$ (14)	$ (16)	$ 11

Change in Unrealized Gain (Loss) on Settlements on Derivatives

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 25
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480238/815-25-50-1

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

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- Definition

Amount of gain (loss) on derivative instrument designated and qualifying as fair value hedge included in assessment of hedge effectiveness, recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480627/815-20-45-1A

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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

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

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