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Schedule IV - (Reinsurance) (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract] |  |  |
Direct Amount | $ 4 | $ 5 | $ (3)
Ceded to Others | 0 | 0 | 0
Assumed from Other Companies | 0 | 0 | 0
Net Amount | $ 4 | $ 5 | $ (3)
Percentage of Amount Assumed to Net | 0.00% | 0.00% | 0.00%

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