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Schedule IV - Reinsurance (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items] |  |  |
Direct Premiums Written | $ (28) | $ (24) | $ (14)
Ceded Premiums Written | 31 | 17 | (2)
Assumed Premiums Written | 0 | 0 | 0
Premiums Written, Net | $ (60) | $ (41) | $ (12)
Percentage of Amount Assumed to Net |  | 0.00% | 0.00%

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