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Investment Securities - Narrative (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 USD ($) security | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |  |
Equity securities without readily determinable fair value | $ 67,900,000 |  |
Upward adjustments of equity securities without readily determinable fair values | 0 | $ 0 |
Downward adjustments of equity securities without readily determinable fair values | 20,000 | 0 |
Impairment of equity securities without readily determinable fair values | 0 | 2,000 |
Pledged securities | $ 7,000,000,000.0 | $ 7,200,000,000 | $ 6,900,000,000
Number of securities by a single non-government sponsored issuer exceeding 10% of shareholders' equity | security | 0 |  |

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