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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 | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | $ 522 | $ 411 | $ 529 | $ 737
Net Economic Loss Development (Benefit) | (125) | (287) | 145 |
Insurance Contracts |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 205 | 364 |  |
Net Economic Loss Development (Benefit) | (112) | (281) | 142 |
Financial Guarantee Variable Interest Entities |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 314 | 42 |  |
Net Economic Loss Development (Benefit) | (17) | (20) | 1 |
Financial Guarantee Accounted for as Credit Derivatives |  |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |  |
Net Expected Loss to be Paid (Recovered) | 3 | 5 |  |
Net Economic Loss Development (Benefit) | $ 4 | $ 14 | $ 2 |

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