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v3.25.1

Business Segments (Revenues by Line of Business) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Total revenues | $ 3,627 | $ 3,444
Total operating revenues | 3,636 | 3,466
Net investment gains (losses) | (9) | (22)
Operating Segments | Specialty |  |
Total revenues | 1,379 | 1,372
Operating Segments | Commercial |  |
Total revenues | 1,565 | 1,386
Operating Segments | International |  |
Total revenues | 344 | 346
Operating Segments | Life & Group |  |
Total revenues | 332 | 341
Operating Segments | Corporate & Other |  |
Total revenues | 19 | 24
Eliminations |  |
Total revenues | (3) | (3)
Management & Professional Liability | Operating Segments | Specialty |  |
Total revenues | 746 | 729
Surety | Operating Segments | Specialty |  |
Total revenues | 188 | 182
Warranty & Alternative Risks | Operating Segments | Specialty |  |
Total revenues | 445 | 461
Middle Market | Operating Segments | Commercial |  |
Total revenues | 466 | 432
Construction | Operating Segments | Commercial |  |
Total revenues | 510 | 455
Small Business | Operating Segments | Commercial |  |
Total revenues | 156 | 154
Other Commercial | Operating Segments | Commercial |  |
Total revenues | 433 | 345
Canada | Operating Segments | International |  |
Total revenues | 94 | 98
Europe | Operating Segments | International |  |
Total revenues | 144 | 143
Hardy | Operating Segments | International |  |
Total revenues | $ 106 | $ 105

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