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Schedule IV - Reinsurance (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Condensed Financial Statements, Captions [Line Items] |  |  |
Direct Premiums Written | $ 2 | $ (1) | $ (28)
Ceded Premiums Written | 35 | (1) | 31
Assumed Premiums Written | 0 | 0 | 0
Premiums Written, Net | $ (33) | $ 0 | $ (60)
Percentage of Amount Assumed to Net | 0.00% | 0.00% | 0.00%

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