v3.25.4

Segment Information (Segments and Geographic Areas) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | $ 26,981 | $ 24,458 | $ 22,736
Compensation and benefits | 15,577 | 13,996 | 13,099
Depreciation and amortization expense | 361 | 369 | 370
Identified intangible amortization expense | 549 | 377 | 343
Other operating expenses | 4,271 | 3,899 | 3,642
Operating income | 6,223 | 5,817 | 5,282
Risk and Insurance Services |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Fiduciary interest income | 403 | 497 | 453
Operating Segments |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | 27,059 | 24,528 | 22,798
Compensation and benefits | 15,421 | 13,857 | 12,951
Depreciation and amortization expense | 304 | 306 | 296
Identified intangible amortization expense | 549 | 377 | 343
Other operating expenses | 4,253 | 3,853 | 3,597
Operating income | 6,532 | 6,135 | 5,611
Operating Segments | Risk and Insurance Services |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | 17,265 | 15,395 | 14,089
Compensation and benefits | 9,711 | 8,499 | 7,702
Depreciation and amortization expense | 204 | 192 | 190
Identified intangible amortization expense | 475 | 326 | 297
Other operating expenses | 2,239 | 2,013 | 1,955
Operating income | 4,636 | 4,365 | 3,945
Fiduciary interest income | 403 | 497 | 453
Gain related to investments in private equity funds and other investments | 24 | 22 | 18
Operating Segments | Risk and Insurance Services | Disposal Group, Disposed of by Sale, Not Discontinued Operations |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Pre-tax gain (loss) on sale | 28 |  |
Operating Segments | Consulting |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | 9,794 | 9,133 | 8,709
Compensation and benefits | 5,710 | 5,358 | 5,249
Depreciation and amortization expense | 100 | 114 | 106
Identified intangible amortization expense | 74 | 51 | 46
Other operating expenses | 2,014 | 1,840 | 1,642
Operating income | 1,896 | 1,770 | 1,666
Operating Segments | Consulting | Marsh Management Consulting |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | 3,604 | 3,390 | 3,122
Pre-tax gain (loss) on sale |  | 20 |
Operating Segments | Consulting | U.S. Health And Benefits And U.K Pension Administration Businesses |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Pre-tax gain (loss) on sale |  | 35 |
Corporate/Eliminations |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | (78) | (70) | (62)
Compensation and benefits | 156 | 139 | 148
Depreciation and amortization expense | 57 | 63 | 74
Identified intangible amortization expense | 0 | 0 | 0
Other operating expenses | 18 | 46 | 45
Operating income | (309) | (318) | (329)
Inter-segment | Consulting |  |  |
Segment Reporting, Asset Reconciling Item [Line Items] |  |  |
Revenue | $ 73 | $ 60 | $ 56

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