Segment Information (Revenues From External Customers And Segment Operating Profit) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information [Line Items]
Income from operations	$ 866	$ 738	$ 2,536	$ 2,141
Revenue	5,415	5,044	15,775	14,654
Other Segment Items	4,533	4,237	13,177	12,356
Financial Services
Segment Reporting Information [Line Items]
Revenue	1,578	1,486	4,587	4,318
Other Segment Items	1,316	1,235	3,817	3,651
Healthcare Segment
Segment Reporting Information [Line Items]
Revenue	1,604	1,514	4,726	4,391
Other Segment Items	1,290	1,261	3,803	3,602
Products and Resources
Segment Reporting Information [Line Items]
Revenue	1,383	1,228	3,967	3,487
Other Segment Items	1,192	1,027	3,384	2,926
Communication, Media and Technology
Segment Reporting Information [Line Items]
Revenue	850	816	2,495	2,458
Other Segment Items	735	714	2,173	2,177
Operating Segments
Segment Reporting Information [Line Items]
Income from operations	882	807	2,598	2,298
Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Income from operations	314	253	923	789
Operating Segments \| Healthcare Segment
Segment Reporting Information [Line Items]
Income from operations	262	251	770	667
Operating Segments \| Products and Resources
Segment Reporting Information [Line Items]
Income from operations	191	201	583	561
Operating Segments \| Communications, Media and Technology
Segment Reporting Information [Line Items]
Income from operations	115	102	322	281
Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting Information [Line Items]
Unallocated costs	$ 16	$ 69	$ 62	$ 157

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