v3.26.3
Revenues and Trade Accounts Receivable - Disaggregation of Revenue (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Disaggregation of Revenue [Line Items]        
Revenue $ 5,664 $ 5,415 $ 16,558 $ 15,775
Time-and-materials        
Disaggregation of Revenue [Line Items]        
Revenue 2,401 2,370 6,917 6,946
Fixed-price        
Disaggregation of Revenue [Line Items]        
Revenue 2,753 2,547 8,167 7,370
Transaction or volume-based        
Disaggregation of Revenue [Line Items]        
Revenue 510 498 1,474 1,459
North America        
Disaggregation of Revenue [Line Items]        
Revenue 4,258 4,028 12,437 11,794
United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 532 503 1,533 1,442
Europe, excluding United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 525 539 1,590 1,552
Europe        
Disaggregation of Revenue [Line Items]        
Revenue 1,057 1,042 3,123 2,994
Rest of World        
Disaggregation of Revenue [Line Items]        
Revenue 349 345 998 987
Consulting And Technology Services        
Disaggregation of Revenue [Line Items]        
Revenue 3,600 3,494 10,609 10,109
Outsourcing Services        
Disaggregation of Revenue [Line Items]        
Revenue 2,064 1,921 5,949 5,666
Healthcare Segment        
Disaggregation of Revenue [Line Items]        
Revenue 1,587 1,604 4,738 4,726
Healthcare Segment | Time-and-materials        
Disaggregation of Revenue [Line Items]        
Revenue 488 506 1,449 1,482
Healthcare Segment | Fixed-price        
Disaggregation of Revenue [Line Items]        
Revenue 797 791 2,406 2,332
Healthcare Segment | Transaction or volume-based        
Disaggregation of Revenue [Line Items]        
Revenue 302 307 883 912
Healthcare Segment | North America        
Disaggregation of Revenue [Line Items]        
Revenue 1,319 1,331 3,937 3,959
Healthcare Segment | United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 63 56 180 156
Healthcare Segment | Europe, excluding United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 165 174 497 500
Healthcare Segment | Europe        
Disaggregation of Revenue [Line Items]        
Revenue 228 230 677 656
Healthcare Segment | Rest of World        
Disaggregation of Revenue [Line Items]        
Revenue 40 43 124 111
Healthcare Segment | Consulting And Technology Services        
Disaggregation of Revenue [Line Items]        
Revenue 948 929 2,786 2,707
Healthcare Segment | Outsourcing Services        
Disaggregation of Revenue [Line Items]        
Revenue 639 675 1,952 2,019
Financial Services        
Disaggregation of Revenue [Line Items]        
Revenue 1,767 1,578 5,144 4,587
Financial Services | Time-and-materials        
Disaggregation of Revenue [Line Items]        
Revenue 878 829 2,506 2,405
Financial Services | Fixed-price        
Disaggregation of Revenue [Line Items]        
Revenue 826 697 2,459 2,035
Financial Services | Transaction or volume-based        
Disaggregation of Revenue [Line Items]        
Revenue 63 52 179 147
Financial Services | North America        
Disaggregation of Revenue [Line Items]        
Revenue 1,279 1,115 3,718 3,254
Financial Services | United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 179 166 515 478
Financial Services | Europe, excluding United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 161 164 494 471
Financial Services | Europe        
Disaggregation of Revenue [Line Items]        
Revenue 340 330 1,009 949
Financial Services | Rest of World        
Disaggregation of Revenue [Line Items]        
Revenue 148 133 417 384
Financial Services | Consulting And Technology Services        
Disaggregation of Revenue [Line Items]        
Revenue 1,280 1,118 3,720 3,237
Financial Services | Outsourcing Services        
Disaggregation of Revenue [Line Items]        
Revenue 487 460 1,424 1,350
Products and Resources        
Disaggregation of Revenue [Line Items]        
Revenue 1,371 1,383 4,014 3,967
Products and Resources | Time-and-materials        
Disaggregation of Revenue [Line Items]        
Revenue 537 589 1,575 1,725
Products and Resources | Fixed-price        
Disaggregation of Revenue [Line Items]        
Revenue 759 704 2,190 1,976
Products and Resources | Transaction or volume-based        
Disaggregation of Revenue [Line Items]        
Revenue 75 90 249 266
Products and Resources | North America        
Disaggregation of Revenue [Line Items]        
Revenue 961 978 2,795 2,807
Products and Resources | United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 162 156 477 441
Products and Resources | Europe, excluding United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 160 167 492 479
Products and Resources | Europe        
Disaggregation of Revenue [Line Items]        
Revenue 322 323 969 920
Products and Resources | Rest of World        
Disaggregation of Revenue [Line Items]        
Revenue 88 82 250 240
Products and Resources | Consulting And Technology Services        
Disaggregation of Revenue [Line Items]        
Revenue 926 981 2,727 2,786
Products and Resources | Outsourcing Services        
Disaggregation of Revenue [Line Items]        
Revenue 445 402 1,287 1,181
Communications, Media and Technology        
Disaggregation of Revenue [Line Items]        
Revenue 939 850 2,662 2,495
Communications, Media and Technology | Time-and-materials        
Disaggregation of Revenue [Line Items]        
Revenue 498 446 1,387 1,334
Communications, Media and Technology | Fixed-price        
Disaggregation of Revenue [Line Items]        
Revenue 371 355 1,112 1,027
Communications, Media and Technology | Transaction or volume-based        
Disaggregation of Revenue [Line Items]        
Revenue 70 49 163 134
Communications, Media and Technology | North America        
Disaggregation of Revenue [Line Items]        
Revenue 699 604 1,987 1,774
Communications, Media and Technology | United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 128 125 361 367
Communications, Media and Technology | Europe, excluding United Kingdom        
Disaggregation of Revenue [Line Items]        
Revenue 39 34 107 102
Communications, Media and Technology | Europe        
Disaggregation of Revenue [Line Items]        
Revenue 167 159 468 469
Communications, Media and Technology | Rest of World        
Disaggregation of Revenue [Line Items]        
Revenue 73 87 207 252
Communications, Media and Technology | Consulting And Technology Services        
Disaggregation of Revenue [Line Items]        
Revenue 446 466 1,376 1,379
Communications, Media and Technology | Outsourcing Services        
Disaggregation of Revenue [Line Items]        
Revenue $ 493 $ 384 $ 1,286 $ 1,116