Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions |
Jun. 30, 2024 |
Dec. 31, 2023 |
|---|---|---|
| Goodwill by segment | ||
| Goodwill | $ 4,250 | $ 3,976 |
| Reportable Segments [Member] | Business Insurance [Member] | ||
| Goodwill by segment | ||
| Goodwill | 2,580 | 2,585 |
| Reportable Segments [Member] | Bond & Specialty Insurance [Member] | ||
| Goodwill by segment | ||
| Goodwill | 835 | 550 |
| Reportable Segments [Member] | Bond & Specialty Insurance [Member] | Corvus [Member] | ||
| Goodwill by segment | ||
| Goodwill | 285 | |
| Amount of goodwill expected to be deductible for tax purposes | 0 | |
| Reportable Segments [Member] | Personal Insurance [Member] | ||
| Goodwill by segment | ||
| Goodwill | 809 | 815 |
| Other [Member] | ||
| Goodwill by segment | ||
| Goodwill | $ 26 | $ 26 |
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- Definition The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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