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Schedule IV - (Reinsurance) (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Supplemental Schedule of Reinsurance Premiums for Insurance Companies [Abstract] |  |  |
Direct Amount | $ (3) | $ 8 | $ 1
Ceded to Others | 0 | 2 | 1
Assumed From Other Companies | 0 | 0 | 0
Net Amount | $ (3) | $ 6 | $ 0
Percentage of Amount Assumed to Net | 0.00% | 0.00% | 0.00%

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