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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, 2026 | Mar. 31, 2025 | Dec. 31, 2025 | Dec. 31, 2024
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | $ 141 | $ 150 | $ 101 | $ 106
Net economic loss development (benefit) | 44 | (15) |  |
Insurance |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 129 |  | 88 |
Net economic loss development (benefit) | 44 | 48 |  |
FG VIEs' assets |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 12 |  | 13 |
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) | $ 0 | $ (63) |  |

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