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v3.23.3

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Segment Reporting Information [Line Items] |  |  |  |
Total premiums earned | $ 1,855 | $ 1,767 | $ 4,799 | $ 4,462
Net investment income | 168 | 151 | 583 | 549
Other income | 43 | 31 | 100 | 93
Revenues before realized gains (losses) | 2,187 | 2,019 | 5,815 | 5,254
Realized gains (losses) on securities | (19) | (35) | (67) | (143)
Realized loss on subsidiary | (4) | 0 | (4) | 0
Total revenues | 2,164 | 1,984 | 5,744 | 5,111
Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total premiums earned | 1,855 | 1,767 | 4,799 | 4,462
Net investment income | 170 | 145 | 568 | 524
Other income | 5 | 2 | 13 | 12
Revenues before realized gains (losses) | 2,030 | 1,914 | 5,380 | 4,998
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues before realized gains (losses) | 157 | 105 | 435 | 256
Property and transportation | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total premiums earned | 828 | 857 | 1,837 | 1,805
Specialty casualty | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total premiums earned | 734 | 677 | 2,149 | 1,973
Specialty financial | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total premiums earned | 232 | 171 | 623 | 505
Other specialty | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total premiums earned | $ 61 | $ 62 | $ 190 | $ 179

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