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v3.24.2

Segment Information (Details of Operating Segment Revenue) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Segment Reporting Information [Line Items] |  |  |  |
Revenue | $ 6,221 | $ 5,876 | $ 12,694 | $ 11,800
Total Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 6,238 | 5,894 | 12,725 | 11,831
Total Segments | Risk and Insurance Services |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 4,022 | 3,722 | 8,295 | 7,628
Total Segments | Risk and Insurance Services | Marsh |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 3,342 | 3,103 | 6,423 | 5,903
Total Segments | Risk and Insurance Services | Guy Carpenter |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 680 | 619 | 1,872 | 1,725
Total Segments | Consulting |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 2,216 | 2,172 | 4,430 | 4,203
Total Segments | Consulting | Mercer |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 1,379 | 1,374 | 2,804 | 2,718
Total Segments | Consulting | Oliver Wyman Group |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | 837 | 798 | 1,626 | 1,485
Corporate/Eliminations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenue | $ (17) | $ (18) | $ (31) | $ (31)

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