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v3.25.2

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 6,974 | $ 6,221 | $ 14,035 | $ 12,694
Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 6,996 | 6,238 | 14,072 | 12,725
Risk and Insurance Services | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Fiduciary interest income | 99 | 125 | 202 | 247
Revenue | 4,625 | 4,022 | 9,387 | 8,295
Risk and Insurance Services | Subtotal | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 4,526 | 3,897 | 9,185 | 8,048
Risk and Insurance Services | Marsh | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 3,849 | 3,265 | 7,302 | 6,268
Revenue | 3,915 | 3,342 | 7,435 | 6,423
Risk and Insurance Services | Guy Carpenter | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 677 | 632 | 1,883 | 1,780
Revenue | 710 | 680 | 1,952 | 1,872
Risk and Insurance Services | Total International | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 1,547 | 1,440 | 3,065 | 2,926
Risk and Insurance Services | EMEA | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 1,006 | 912 | 2,065 | 1,937
Risk and Insurance Services | Asia Pacific | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 409 | 391 | 744 | 727
Risk and Insurance Services | Latin America | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 132 | 137 | 256 | 262
Risk and Insurance Services | U.S./Canada | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue, excluding fiduciary interest income | 2,302 | 1,825 | 4,237 | 3,342
Consulting | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 2,371 | 2,216 | 4,685 | 4,430
Consulting | Mercer | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,498 | 1,379 | 2,994 | 2,804
Consulting | Mercer | Wealth | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 685 | 612 | 1,355 | 1,284
Consulting | Mercer | Health | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 594 | 547 | 1,202 | 1,085
Consulting | Mercer | Career | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 219 | 220 | 437 | 435
Consulting | Oliver Wyman Group | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 873 | $ 837 | $ 1,691 | $ 1,626

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