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Investment Securities - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Marketable Securities [Abstract] |  |  |  |  |
Gains (losses) on available-for-sale securities | $ 0 | $ 0 | $ 0 | $ 0 |
Available-for-sale, accrued interest, after allowance for credit loss | 28,000,000 |  | 28,000,000 |  | $ 29,000,000
Transfers between available for sale and held to maturity debt securities | 0 | 0 | 0 | 0 |
Held-to-maturity, accrued interest, after allowance for credit loss | 3,000,000 |  | 3,000,000 |  | 3,000,000
Allowance for credit loss | 0 |  | 0 |  | 0
Carrying amount of equity investments without a readily determinable fair value | 109,000,000 |  | 109,000,000 |  | $ 96,000,000
Unrealized (losses) gains for equity investments with readily determinable fair values (prior year QTD less than) | $ 6,000,000 | $ 2,000,000 | $ 3,000,000 | $ 7,000,000 |

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