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Derivative Financial Instruments - Information about Hedged Items Included in Consolidated Balance Sheet (Detail) - Designated as Hedging Instrument - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Long-term borrowings | Carrying Amount |  |
Derivatives, Fair Value [Line Items] |  |
Hedged Item | $ 5,184 | $ 2,954
Long-term borrowings | Estimated Fair Value |  |
Derivatives, Fair Value [Line Items] |  |
Hedged Item | (155) | (44)
Investment securities available for sale | Carrying Amount |  |
Derivatives, Fair Value [Line Items] |  |
Hedged Item | 381 |
Investment securities available for sale | Estimated Fair Value |  |
Derivatives, Fair Value [Line Items] |  |
Hedged Item | $ 0 |

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