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v3.23.1

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Segment Reporting Information [Line Items] |  |
Total premiums earned | $ 1,437 | $ 1,302
Net investment income | 217 | 230
Other income | 32 | 30
Revenues before realized gains (losses) | 1,786 | 1,603
Realized gains (losses) on securities | (46) | (15)
Total revenues | 1,740 | 1,588
Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 1,437 | 1,302
Net investment income | 207 | 223
Other income | 5 | 4
Revenues before realized gains (losses) | 1,649 | 1,529
Other |  |
Segment Reporting Information [Line Items] |  |
Revenues before realized gains (losses) | 137 | 74
Property and transportation | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 475 | 443
Specialty casualty | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 704 | 639
Specialty financial | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | 196 | 163
Other specialty | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Total premiums earned | $ 62 | $ 57

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