Segment Information (Revenues From External Customers And Segment Operating Profit) (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) Segment	Sep. 30, 2025 USD ($)
Segment Reporting [Line Items]
Number of Reportable Segments \| Segment			4
Income from operations	$ 872	$ 866	$ 2,589	$ 2,536
Revenue	5,664	5,415	16,558	15,775
Other Segment Items	4,741	4,549	13,915	13,301
Healthcare Segment
Segment Reporting [Line Items]
Revenue	1,587	1,604	4,738	4,726
Other Segment Items	1,266	1,293	3,790	3,835
Financial Services
Segment Reporting [Line Items]
Revenue	1,767	1,578	5,144	4,587
Other Segment Items	1,484	1,313	4,332	3,829
Products and Resources
Segment Reporting [Line Items]
Revenue	1,371	1,383	4,014	3,967
Other Segment Items	1,184	1,205	3,484	3,443
Communications, Media and Technology
Segment Reporting [Line Items]
Revenue	939	850	2,662	2,495
Other Segment Items	807	738	2,309	2,194
Operating Segments
Segment Reporting [Line Items]
Income from operations	923	866	2,643	2,474
Operating Segments \| Healthcare Segment
Segment Reporting [Line Items]
Income from operations	321	311	812	758
Operating Segments \| Financial Services
Segment Reporting [Line Items]
Income from operations	283	265	948	891
Operating Segments \| Products and Resources
Segment Reporting [Line Items]
Income from operations	187	178	530	524
Operating Segments \| Communications, Media and Technology
Segment Reporting [Line Items]
Income from operations	132	112	353	301
Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting [Line Items]
Unallocated costs	$ (51)	$ 0	$ (54)	$ 62

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