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v3.25.3

Debt Securities (Narrative) (Details) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 USD ($) | Mar. 31, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) security | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) security
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Debt Securities Transferred from Available for Sale to Held to Maturity, Amortized Cost | $ 2,000 | $ 1,000 |  |  |  |
Debt securities available for sale |  |  |  | $ 26,886 |  | $ 26,224
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | security |  |  |  | 1,405 |  | 1,722
Unrealized gains (losses) on securities available for sale: |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
OCIDebtSecuritiesAvailableForSaleUnrealizedGainLossTransferredToHeldToMaturityArisingDuringBeforeTax | $ 74 | $ 153 | $ 436 | $ 227 | $ 436 |
Asset Pledged as Collateral |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Debt securities available for sale |  |  |  | $ 21,000 |  | $ 20,900

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