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v3.23.2

Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 5,876 | $ 5,379 | $ 11,800 | $ 10,928
Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 5,894 | 5,397 | 11,831 | 10,956
Risk and Insurance Services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 3,722 | 3,313 | 7,628 | 6,862
Fiduciary interest income | 108 | 13 | 199 | 17
Risk and Insurance Services | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 3,722 | 3,313 | 7,628 | 6,862
Fiduciary interest income | 108 | 13 | 199 | 17
Loss on consolidation of business |  |  |  | 27
Risk and Insurance Services | Total International |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,352 | 1,245 | 2,711 | 2,512
Risk and Insurance Services | EMEA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 858 | 780 | 1,790 | 1,649
Risk and Insurance Services | Asia Pacific |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 357 | 347 | 669 | 641
Risk and Insurance Services | Latin America |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 137 | 118 | 252 | 222
Risk and Insurance Services | U.S./Canada |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,686 | 1,533 | 3,071 | 2,812
Consulting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 2,172 | 2,084 | 4,203 | 4,094
Consulting | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 2,172 | 2,084 | 4,203 | 4,094
Consulting | Wealth |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 637 | 597 | 1,218 | 1,214
Consulting | Health |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 518 | 587 | 1,063 | 1,111
Consulting | Career |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 219 | 205 | 437 | 407
Oliver Wyman Group | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Loss on consolidation of business |  |  |  | 12
Small Individual Financial Advisory Business | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Pre-tax gain (loss) on sale |  |  | (17) |
Mercer U.S. Affinity Business | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Pre-tax gain (loss) on sale |  | 112 |  | 112
Marsh & Guy Carpenter | Risk and Insurance Services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 3,614 | 3,300 | 7,429 | 6,845
Marsh | Risk and Insurance Services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 3,038 | 2,778 | 5,782 | 5,324
Marsh | Risk and Insurance Services | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 3,103 | 2,787 | 5,903 | 5,336
Guy Carpenter | Risk and Insurance Services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 576 | 522 | 1,647 | 1,521
Guy Carpenter | Risk and Insurance Services | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 619 | 526 | 1,725 | 1,526
Mercer | Consulting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,374 | 1,389 | 2,718 | 2,732
Mercer | Consulting | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,374 | 1,389 | 2,718 | 2,732
Oliver Wyman Group | Consulting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 798 | 695 | 1,485 | 1,362
Oliver Wyman Group | Consulting | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 798 | $ 695 | $ 1,485 | $ 1,362

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