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Derivative Financial Instruments - Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet (Detail) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | $ 255 | $ 324
Liability Derivatives | 822 | 943
Fair Value Hedges |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 206 | 256
Liability Derivatives | 787 | 898
Fair Value Hedges | Designated as Hedging Instrument |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 6 | 18
Liability Derivatives | 3 | 10
Fair Value Hedges | Derivatives Not Designated and Qualifying as Hedging Instruments |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 43 | 50
Liability Derivatives | 32 | 35
Interest rate swap agreements | Fair Value Hedges | Designated as Hedging Instrument |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 2 | 12
Liability Derivatives | 3 | 2
Commitments to sell real estate loans | Designated as Hedging Instrument |  |
Derivatives, Fair Value [Line Items] |  |
Liability Derivatives | 0 |
Commitments to sell real estate loans | Fair Value Hedges | Designated as Hedging Instrument |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 4 | 6
Liability Derivatives |  | 8
Commitments to sell real estate loans | Fair Value Hedges | Derivatives Not Designated and Qualifying as Hedging Instruments |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 39 | 35
Liability Derivatives | 0 | 3
Commitments to originate real estate loans for sale | Fair Value Hedges | Derivatives Not Designated and Qualifying as Hedging Instruments |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 4 | 15
Liability Derivatives | 32 | 32
Interest Rate Contracts | Fair Value Hedges | Derivatives Not Designated and Qualifying as Hedging Instruments |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 185 | 237
Liability Derivatives | 769 | 879
Foreign exchange and other option and futures contracts | Fair Value Hedges | Derivatives Not Designated and Qualifying as Hedging Instruments |  |
Derivatives, Fair Value [Line Items] |  |
Asset Derivatives | 21 | 19
Liability Derivatives | $ 18 | $ 19

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