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v3.25.3

Premium Income by Major Line of Business within Each Segment (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information |  |  |  |
Premium Income | $ 2,688.0 | $ 2,628.8 | $ 8,138.9 | $ 7,866.3
Operating Segments |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 2,688.0 | 2,628.8 | 8,138.9 | 7,866.3
Operating Segments | Unum US |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 1,755.4 | 1,723.5 | 5,334.9 | 5,161.8
Operating Segments | Unum US | Group Long-term Disability |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 499.2 | 522.1 | 1,511.5 | 1,560.3
Operating Segments | Unum US | Group Short-term Disability |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 286.0 | 271.3 | 853.6 | 810.7
Operating Segments | Unum US | Group Life |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 468.3 | 447.8 | 1,404.5 | 1,337.9
Operating Segments | Unum US | Accidental Death & Dismemberment |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 48.9 | 47.1 | 146.3 | 139.3
Operating Segments | Unum US | Voluntary Benefits |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 231.6 | 219.3 | 700.2 | 665.1
Operating Segments | Unum US | Individual Disability |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 140.0 | 140.4 | 475.4 | 424.6
Operating Segments | Unum US | Dental and Vision |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 81.4 | 75.5 | 243.4 | 223.9
Operating Segments | Unum International |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 281.1 | 246.6 | 798.9 | 707.1
Operating Segments | Unum International | Group Long-term Disability |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 111.3 | 106.6 | 319.4 | 312.4
Operating Segments | Unum International | Group Life |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 71.9 | 58.8 | 201.6 | 156.3
Operating Segments | Unum International | Supplemental |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 47.4 | 41.4 | 136.3 | 125.1
Operating Segments | Unum International | Unum Poland |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 50.5 | 39.8 | 141.6 | 113.3
Operating Segments | Colonial Life |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 456.5 | 441.9 | 1,375.9 | 1,335.0
Operating Segments | Colonial Life | Accident, Sickness, and Disability |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 247.5 | 240.6 | 743.7 | 725.5
Operating Segments | Colonial Life | Life |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 118.7 | 113.1 | 360.7 | 342.6
Operating Segments | Colonial Life | Cancer and Critical Illness Colonial |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 90.3 | 88.2 | 271.5 | 266.9
Operating Segments | Closed Block |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 195.0 | 216.8 | 629.2 | 662.4
Operating Segments | Closed Block | Long-term Care |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | 158.6 | 173.7 | 510.7 | 521.5
Operating Segments | Closed Block | Other Insurance Product Line |  |  |  |
Segment Reporting Information |  |  |  |
Premium Income | $ 36.4 | $ 43.1 | $ 118.5 | $ 140.9

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