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v3.25.1

Investment Securities - Additional Information (Detail) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 USD ($) security | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($)
Summary of Investment Holdings [Line Items] |  |  |
Gross realized gains (loss) on sale of investment securities | $ 0 | $ 0 |
Gains (losses) on equity securities | $ 0 | $ 2,000,000 |
Number of debt securities with aggregate gross unrealized losses | security | 3,597 |  |
Unrealized losses on individual debt securities | $ 1,200,000,000 |  |
Cost method equity securities | 706,000,000 |  |
Allowance for credit losses | 0 |  | $ 0
Investment securities pledged to secure debt carrying value | 6,100,000,000 |  | 6,200,000,000
Carrying value of investment securities pledged related to repurchase transactions | $ 71,000,000 |  | $ 71,000,000

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