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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 | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Jun. 30, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Dec. 31, 2021
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |  |  |  |  |
Net Expected Loss to be Paid (Recovered) | $ 490 | $ 727 | $ 490 | $ 727 | $ 560 | $ 522 | $ 442 | $ 411
Net economic loss development (benefit) | 87 | (72) | 147 | (148) |  |  |  |
Insurance |  |  |  |  |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |  |  |  |  |
Net Expected Loss to be Paid (Recovered) | 252 |  | 252 |  |  | 205 |  |
Net economic loss development (benefit) | 92 | (67) | 160 | (137) |  |  |  |
FG VIEs' assets |  |  |  |  |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |  |  |  |  |
Net Expected Loss to be Paid (Recovered) | 235 |  | 235 |  |  | 314 |  |
Net economic loss development (benefit) | (6) | (6) | (15) | (16) |  |  |  |
Credit derivatives |  |  |  |  |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |  |  |  |  |
Net Expected Loss to be Paid (Recovered) | 3 |  | 3 |  |  | $ 3 |  |
Net economic loss development (benefit) | $ 1 | $ 1 | $ 2 | $ 5 |  |  |  |

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