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v3.22.4

Segment Information (Details For MMC's Operating Segments) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Segment Reporting Information [Line Items] |  |  |
Revenue | $ 20,720 | $ 19,820 | $ 17,224
Operating Income (Loss) | 4,280 | 4,312 | 3,066
Total Assets | 33,454 | 34,388 | 33,049
Depreciation and Amortization | 719 | 747 | 741
Capital Expenditures | 470 | 406 | 348
Equity method investments | 215 | 207 |
Risk and Insurance Services |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | 12,645 | 12,085 | 10,337
Interest income, fiduciary assets | 120 | 15 | 46
Consulting |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | 8,139 | 7,789 | 6,976
Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | 20,784 | 19,874 | 17,313
Operating Income (Loss) | 4,642 | 4,584 | 3,340
Total Assets | 32,808 | 32,342 | 30,183
Depreciation and Amortization | 627 | 676 | 674
Capital Expenditures | 392 | 323 | 277
Pre-tax gain on sale |  | (50) |
Operating Segments | Risk and Insurance Services |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | 12,645 | 12,085 | 10,337
Operating Income (Loss) | 3,089 | 3,080 | 2,346
Total Assets | 22,776 | 21,996 | 20,612
Depreciation and Amortization | 469 | 505 | 500
Capital Expenditures | 283 | 214 | 170
Interest income, fiduciary assets | 120 | 15 | 46
Equity method income | 12 | 31 | 27
Gain (loss) on consolidation of business | (27) |  |
Pre-tax gain on sale |  | (50) |
Equity method investments | 50 | 53 | 165
Operating Segments | Consulting |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | 8,139 | 7,789 | 6,976
Operating Income (Loss) | 1,553 | 1,504 | 994
Total Assets | 10,032 | 10,346 | 9,571
Depreciation and Amortization | 158 | 171 | 174
Capital Expenditures | 109 | 109 | 107
Equity method income | 1 |  | 5
Equity method investments | 6 | 5 | 5
Operating Segments | Marsh India |  |  |
Segment Reporting Information [Line Items] |  |  |
Pre-tax gain on sale |  | (267) |
Corporate/Eliminations |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | (64) | (54) | (89)
Operating Income (Loss) | (362) | (272) | (274)
Total Assets | 646 | 2,046 | 2,866
Depreciation and Amortization | 92 | 71 | 67
Capital Expenditures | 78 | 83 | 71
Inter-segment | Risk and Insurance Services |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | 5 | 5 | 5
Inter-segment | Consulting |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenue | $ 59 | $ 49 | $ 84

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