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Investment Securities - Additional Information (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Debt Securities, Available-for-sale [Line Items] |  |
Accrued interest receivable | $ 262 | $ 227
Investment securities | 39,400 | 45,100
Securities received as collateral | $ 18 | $ 16
Investment securities available for sale | Government Contracts Concentration Risk | US Treasury and Agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Percentage of portfolio | 96.00% | 97.00%

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