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Contracts Accounted for as Insurance - Effect of Reinsurance on Premiums Written, Premiums Earned and Loss and LAE (Benefit) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Premiums Written: |  |  |
Direct | $ 436 | $ 307 | $ 377
Assumed | 4 | 50 | (17)
Ceded | (6) | (16) | 0
Net | 434 | 341 | 360
Premiums Earned: |  |  |
Direct | 378 | 319 | 469
Assumed | 32 | 28 | 28
Ceded | (7) | (3) | (3)
Net earned premiums | 403 | 344 | 494
Loss and LAE (benefit): |  |  |
Direct | (30) | 157 | 32
Assumed | 3 | 8 | (17)
Ceded | 1 | (3) | 1
Loss and LAE (benefit) | $ (26) | $ 162 | $ 16

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