DERIVATIVES - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Derivative [Line Items]
Notional Amount	$ 278,332	$ 279,484
Net loss (pre-tax) on derivatives expected to be reclassified in next 12 months	612
Prepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedged assets	4,700	4,700
Nonprepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedged assets	3,200	$ 3,100
Interest rate contracts \| Cash Flow Hedging
Derivative [Line Items]
Notional Amount	$ 1,500

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