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Business Combinations (Details) - USD ($) $ in Millions |  | 3 Months Ended
--- | --- | ---
Feb. 19, 2024 | Mar. 31, 2025
Business Acquisition [Line Items] |  |
Entity shares issued (in shares) | 1.0192 |
Business combination, acquisition related costs |  | $ 110
Business combination, acquisition related cost, recognized |  | $ 344
Series D Preferred Stock | Discover |  |
Business Acquisition [Line Items] |  |
Per annum dividend rate | 6.125% |

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