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Expected Loss to be Paid (Recovered) - Net Economic Loss Development (Benefit) U.S. RMBS (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Schedule of Expected Losses to be Paid [Line Items] |  |  |
Economic Loss Development (Benefit) | $ (125) | $ (287) | $ 145
U.S. | RMBS |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |
Economic Loss Development (Benefit) | (143) | (100) | (71)
First Lien | U.S. | RMBS |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |
Economic Loss Development (Benefit) | 36 | 0 | (45)
Second Lien | U.S. | RMBS |  |  |
Schedule of Expected Losses to be Paid [Line Items] |  |  |
Economic Loss Development (Benefit) | $ (107) | $ (100) | $ (26)

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