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v3.25.3

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Net earned premiums | $ 2,013 | $ 2,055 | $ 5,240 | $ 5,186
Net investment income | 205 | 200 | 562 | 586
Other income | 30 | 26 | 84 | 92
Revenues before realized gains (losses) | 2,318 | 2,371 | 6,093 | 6,165
Realized gains (losses) on securities | 12 | (2) | 17 | 10
Realized gain on subsidiaries | 1 | 0 | 1 | 0
Total revenues | 2,331 | 2,369 | 6,111 | 6,175
Operating segments | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net earned premiums | 2,013 | 2,055 | 5,240 | 5,186
Net investment income | 205 | 195 | 554 | 589
Other income | 6 | 2 | 9 | 6
Revenues before realized gains (losses) | 2,224 | 2,252 | 5,803 | 5,781
Operating segments | Property and Casualty Insurance | Property and transportation |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net earned premiums | 935 | 989 | 2,011 | 2,061
Operating segments | Property and Casualty Insurance | Specialty casualty |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net earned premiums | 810 | 797 | 2,403 | 2,371
Operating segments | Property and Casualty Insurance | Specialty financial |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net earned premiums | 268 | 269 | 826 | 754
Operating segments | Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues before realized gains (losses) | $ 94 | $ 119 | $ 290 | $ 384

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