Reinsurance - Consolidated Property Casualty Insurance Assumed and Ceded Business (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Property Casualty Insurance Assumed And Ceded Business | ||||
| Earned premiums | $ 2,690 | $ 2,567 | $ 7,929 | $ 7,391 |
| Incurred loss and loss expenses | 1,675 | 1,540 | 5,313 | 5,168 |
| Consolidated Property And Casualty Insurance | ||||
| Property Casualty Insurance Assumed And Ceded Business | ||||
| Direct written premiums | 2,509 | 2,482 | 7,755 | 7,542 |
| Assumed written premiums | 127 | 98 | 624 | 597 |
| Ceded written premiums | (86) | (87) | (336) | (418) |
| Net written premiums | 2,550 | 2,493 | 8,043 | 7,721 |
| Direct earned premiums | 2,546 | 2,440 | 7,473 | 7,020 |
| Assumed earned premiums | 171 | 162 | 508 | 514 |
| Ceded earned premiums | (112) | (118) | (309) | (389) |
| Earned premiums | 2,605 | 2,484 | 7,672 | 7,145 |
| Direct incurred loss and loss expenses | 1,513 | 1,408 | 4,867 | 5,065 |
| Assumed incurred loss and loss expenses | 108 | 78 | 273 | 405 |
| Ceded incurred loss and loss expenses | (26) | (22) | (70) | (532) |
| Incurred loss and loss expenses | $ 1,595 | $ 1,464 | $ 5,070 | $ 4,938 |
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- Definition [Line Items] for Property Casualty Insurance Premiums Written On Assumed And Ceded Business No definition available.
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- Definition Amount of earned premiums assumed from other entities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of written premiums assumed from other entities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of earned premiums ceded to other entities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of written premiums ceded to other entities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The increase (decrease) in property and casualty insurance liabilities balances during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before effect of policies assumed or ceded, of expense related to provision for policy benefits and costs incurred. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of policy benefits and costs incurred for policies assumed. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of reduction of provision for policy benefits and costs incurred for policies ceded. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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