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Derivative Financial Instruments - Notional Amount of Interest Rate Swap Agreements Outstanding Maturity (Detail) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |
Total | $ 36,184 | $ 26,977
Interest rate swap agreements |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |
2025 | 10,384 |
2026 | 10,450 |
2027 | 6,000 |
2028 | 6,500 |
2029 | 0 |
Later years | 2,850 |
Total | $ 36,184 |

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