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v3.24.1.u1

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Segment Reporting Information [Line Items] |  |
Total premiums earned | $ 1,546 | $ 1,437
Net investment income | 198 | 217
Other income | 39 | 32
Revenues before realized gains (losses) | 1,892 | 1,786
Realized gains (losses) on securities | 14 | (46)
Total revenues | 1,906 | 1,740
Operating Segments | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 1,546 | 1,437
Net investment income | 205 | 207
Other income | 2 | 5
Revenues before realized gains (losses) | 1,753 | 1,649
Operating Segments | Property and Casualty Insurance | Property and transportation |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 513 | 475
Operating Segments | Property and Casualty Insurance | Specialty casualty |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 730 | 704
Operating Segments | Property and Casualty Insurance | Specialty financial |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 243 | 196
Operating Segments | Property and Casualty Insurance | Other specialty |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 60 | 62
Operating Segments | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues before realized gains (losses) | $ 139 | $ 137

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