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Commitments, Contingencies, Guarantees and Others - Other Contingencies (Details) - USD ($) $ in Millions | 11 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2024
Loss Contingencies [Line Items] |  |
Loss contingency, estimate of possible loss |  | $ 600
FDIC Special Assessment |  |
Loss Contingencies [Line Items] |  |
Operating expenses | $ 289 | 325
Loss contingency, estimate of possible loss |  | $ 200

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