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v3.24.3

Segment Information (Details of Operating Segment Revenue) (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] |  |  |  |
Revenue | $ 5,697 | $ 5,382 | $ 18,391 | $ 17,182
Total Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 5,715 | 5,396 | 18,440 | 17,227
Total Segments | Risk and Insurance Services |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 3,453 | 3,190 | 11,748 | 10,818
Total Segments | Risk and Insurance Services | Marsh |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 3,023 | 2,782 | 9,446 | 8,685
Total Segments | Risk and Insurance Services | Guy Carpenter |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 430 | 408 | 2,302 | 2,133
Total Segments | Consulting |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 2,262 | 2,206 | 6,692 | 6,409
Total Segments | Consulting | Mercer |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 1,452 | 1,425 | 4,256 | 4,143
Total Segments | Consulting | Oliver Wyman Group |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 810 | 781 | 2,436 | 2,266
Corporate/Eliminations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | $ (18) | $ (14) | $ (49) | $ (45)

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