DERIVATIVES - Amounts Recorded in Balance Sheet (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (19)	$ (17)
Closed Portfolios
Derivative [Line Items]
Carrying amount of hedged assets	4,800	4,000
Amortized cost	6,800	5,900
Cumulative basis adjustment	(58)	39
Total debt securities available for sale, at fair value
Derivative [Line Items]
Carrying amount of hedged assets	9,125	7,253
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged assets	(74)	60
Long-term borrowed funds
Derivative [Line Items]
Carrying amount of hedged liabilities	480	483
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (19)	$ (17)

Debt Securities, Available-for-Sale, Cumulative Basis Adjustment

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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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.

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Amount of asset hedged in fair value hedging relationship.

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

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Amount of liability hedged in fair value hedging relationship.

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

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