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v3.24.3

Segment Information (Financial Information with Respect to Business Segments) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | $ 1,577.7 | $ 1,522.7 | $ 4,694.5 | $ 4,496.5
Net realized and unrealized investment losses | (12.4) | (6.1) | (41.4) | (31.8)
Total revenues | 1,565.3 | 1,516.6 | 4,653.1 | 4,464.7
Net investment income | 91.8 | 84.2 | 271.9 | 250.5
Operating income (loss) before interest expense and income taxes | 150.6 | 13.7 | 395.7 | (52.5)
Interest on debt | (8.5) | (8.5) | (25.6) | (25.6)
Operating income (loss) before income taxes | 142.1 | 5.2 | 370.1 | (78.1)
Other non-operating | 0.0 |  | (2.4) | 0.8
Income (loss) from continuing operations before income taxes | 129.7 | (0.9) | 326.3 | (109.1)
Core Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 576.6 | 557.1 | 1,727.6 | 1,658.2
Underwriting (loss) income | 14.6 | 5.3 | 88.3 | 1.0
Net investment income | 42.1 | 38.4 | 124.3 | 114.2
Other income (expense) | (0.8) | (0.6) | (2.0) | (0.8)
Operating income (loss) before interest expense and income taxes | 55.9 | 43.1 | 210.6 | 114.4
Specialty [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 353.7 | 340.9 | 1,049.0 | 1,011.6
Underwriting (loss) income | 52.6 | 52.7 | 113.5 | 119.5
Net investment income | 20.9 | 18.0 | 61.7 | 53.6
Other income (expense) | (0.5) | (0.4) | (0.8) | (0.1)
Operating income (loss) before interest expense and income taxes | 73.0 | 70.3 | 174.4 | 173.0
Personal Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 644.9 | 620.5 | 1,908.5 | 1,815.1
Underwriting (loss) income | (6.7) | (127.3) | (74.4) | (422.4)
Net investment income | 26.3 | 24.3 | 77.9 | 73.3
Other income (expense) | 2.1 | 2.6 | 6.7 | 8.0
Operating income (loss) before interest expense and income taxes | 21.7 | (100.4) | 10.2 | (341.1)
Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 2.5 | 4.2 | 9.4 | 11.6
Net investment income | 2.5 | 3.5 | 8.0 | 9.4
Other income (expense) | $ (2.5) | (2.8) | (7.5) | (8.2)
Operating income (loss) before interest expense and income taxes |  | $ 0.7 | $ 0.5 | $ 1.2

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