DERIVATIVES - Amounts Recorded in Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Derivative [Line Items]
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (4)	$ (8)
Closed Portfolios
Derivative [Line Items]
Amortized cost	6,200	6,400
Cumulative basis adjustment	29	(75)
Nonprepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedged assets	3,400	3,100
Prepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedged assets	4,700	4,700
Total debt securities available for sale, at fair value
Derivative [Line Items]
Carrying amount of hedged assets	9,718	9,557
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged assets	71	(97)
Long-term borrowed funds
Derivative [Line Items]
Carrying amount of hedged liabilities	496	491
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (4)	$ (8)

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).

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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. Excludes cumulative basis adjustment related to foreign exchange 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. Excludes cumulative basis adjustment related to foreign exchange risk.

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