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Expected Loss to be Paid (Recovered) - Net Expected Loss to be Paid (Recovered) and Net Economic Loss Development (Benefit) by Accounting Model (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024 | Dec. 31, 2023
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | $ 150 | $ 433 | $ 106 | $ 505
Net economic loss development (benefit) | (15) | (7) |  |
Insurance |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 133 |  | 90 |
Net economic loss development (benefit) | 48 | (7) |  |
FG VIEs' assets |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 17 |  | 16 |
Net economic loss development (benefit) | 0 | 0 |  |
Credit derivatives |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 0 |  | $ 0 |
Net economic loss development (benefit) | $ (63) | $ 0 |  |

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