Segment Information (Revenues From External Customers And Segment Operating Profit) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) Segment	Jun. 30, 2025 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| Segment			4
Income from operations	$ 874	$ 817	$ 1,717	$ 1,670
Revenue	5,481	5,245	10,894	10,360
Other Segment Items	4,604	4,428	9,174	8,752
Healthcare Segment
Segment Reporting Information [Line Items]
Revenue	1,572	1,551	3,151	3,122
Other Segment Items	1,260	1,259	2,524	2,542
Financial Services
Segment Reporting Information [Line Items]
Revenue	1,733	1,547	3,377	3,009
Other Segment Items	1,456	1,297	2,848	2,516
Products and Resources
Segment Reporting Information [Line Items]
Revenue	1,322	1,306	2,643	2,584
Other Segment Items	1,157	1,139	2,300	2,238
Communications, Media and Technology
Segment Reporting Information [Line Items]
Revenue	854	841	1,723	1,645
Other Segment Items	731	733	1,502	1,456
Operating Segments
Segment Reporting Information [Line Items]
Income from operations	877	817	1,720	1,608
Operating Segments \| Healthcare Segment
Segment Reporting Information [Line Items]
Income from operations	312	292	529	493
Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Income from operations	277	250	627	580
Operating Segments \| Products and Resources
Segment Reporting Information [Line Items]
Income from operations	165	167	343	346
Operating Segments \| Communications, Media and Technology
Segment Reporting Information [Line Items]
Income from operations	123	108	221	189
Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting Information [Line Items]
Unallocated costs	$ (3)	$ 0	$ (3)	$ 62

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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