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v3.25.2

Revenue from Contracts with Customers - Schedule of 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] |  |  |  |
Total revenue | $ 4,155 | $ 3,760 | $ 8,884 | $ 7,830
U.S. |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 2,040 | 1,837 | 4,042 | 3,349
Americas other than U.S. |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 395 | 362 | 769 | 685
U.K. |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 610 | 548 | 1,231 | 1,131
Ireland |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 46 | 35 | 91 | 68
Europe, Middle East, & Africa other than U.K. and Ireland |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 634 | 566 | 1,896 | 1,775
Asia Pacific |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 430 | 412 | 855 | 822
Operating Segments | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 2,866 | 2,650 | 6,057 | 5,625
Operating Segments | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 1,291 | 1,125 | 2,836 | 2,228
Operating Segments | U.S. | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 1,324 | 1,217 | 2,545 | 2,295
Operating Segments | U.S. | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 718 | 635 | 1,506 | 1,077
Operating Segments | Americas other than U.S. | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 285 | 260 | 539 | 487
Operating Segments | Americas other than U.S. | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 110 | 102 | 230 | 198
Operating Segments | U.K. | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 411 | 379 | 841 | 790
Operating Segments | U.K. | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 199 | 169 | 390 | 341
Operating Segments | Ireland | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 24 | 20 | 46 | 36
Operating Segments | Ireland | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 22 | 15 | 45 | 32
Operating Segments | Europe, Middle East, & Africa other than U.K. and Ireland | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 469 | 428 | 1,415 | 1,356
Operating Segments | Europe, Middle East, & Africa other than U.K. and Ireland | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 165 | 138 | 481 | 419
Operating Segments | Asia Pacific | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 353 | 346 | 671 | 661
Operating Segments | Asia Pacific | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 77 | 66 | 184 | 161
Eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | (2) | (15) | (9) | (23)
Eliminations | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 1 | 10 | 5 | 16
Eliminations | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 2 | 5 | 4 | 7
Corporate/Eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | (2) | (15) | (9) | (23)
Corporate/Eliminations | U.S. |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | (2) | (15) | (9) | (23)
Corporate/Eliminations | Americas other than U.S. |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 0 | 0 | 0 | 0
Corporate/Eliminations | U.K. |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 0 | 0 | 0 | 0
Corporate/Eliminations | Ireland |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 0 | 0 | 0 | 0
Corporate/Eliminations | Europe, Middle East, & Africa other than U.K. and Ireland |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 0 | 0 | 0 | 0
Corporate/Eliminations | Asia Pacific |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 0 | 0 | 0 | 0
Commercial Risk Solutions | Operating Segments | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 2,178 | 2,015 | 4,180 | 3,823
Reinsurance Solutions | Operating Segments | Risk Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 688 | 635 | 1,877 | 1,802
Health Solutions | Operating Segments | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | 772 | 662 | 1,798 | 1,395
Wealth Solutions | Operating Segments | Human Capital |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total revenue | $ 519 | $ 463 | $ 1,038 | $ 833

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