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Investment Securities (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Interest Receivable | $ 38 | $ 40 |
Floating rate securities | 3 | 4 |
Repositioned U.S. Treasury securities | (827) |  |
Net securities losses | (19) | $ 0 | $ 0
Carrying value of securities pledged | 7,000 |  |
Pledged to the FHLB as collateral for potential future borrowings - investment securities | 6,000 |  |
Collateral for potential future borrowings | 1,000 |  |
Liabilities secured by pledged collateral | 357 |  |
Debt securities |  |  |
Securities losses | $ (19) |  |

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