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Schedule IV - Reinsurance (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items] |  |  |
Direct Premiums Written | $ (1) | $ (28) | $ (24)
Ceded Premiums Written | (1) | 31 | 17
Assumed Premiums Written | 0 | 0 | 0
Premiums Written, Net | $ 0 | $ (60) | $ (41)
Percentage of Amount Assumed to Net | 0.00% | 0.00% | 0.00%

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- Definition Amount of written premiums assumed from other entities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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- Definition Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
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