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Commitments, Contingencies, Guarantees and Others - Other Contingencies (Details) $ in Millions | 9 Months Ended | 11 Months Ended
--- | --- | ---
Sep. 30, 2024 USD ($) | Sep. 30, 2024 USD ($)
Loss Contingencies [Line Items] |  |
Loss contingency, estimate of possible loss | $ 400 | $ 400
FDIC Special Assessment |  |
Loss Contingencies [Line Items] |  |
Operating expenses | 330 | 289
Loss contingency, estimate of possible loss | $ 200 | $ 200

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