Segment Information (Revenues From External Customers And Segment Operating Profit) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Income from operations	$ 853	$ 695
Revenue	5,115	4,760
Other Segment Items	4,258	4,019
Financial Services
Segment Reporting Information [Line Items]
Revenue	1,462	1,385
Other Segment Items	1,208	1,177
Healthcare Segment
Segment Reporting Information [Line Items]
Revenue	1,571	1,416
Other Segment Items	1,265	1,154
Products and Resources
Segment Reporting Information [Line Items]
Revenue	1,278	1,133
Other Segment Items	1,073	952
Communication, Media and Technology
Segment Reporting Information [Line Items]
Revenue	804	826
Other Segment Items	712	736
Operating Segments
Segment Reporting Information [Line Items]
Income from operations	857	741
Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Income from operations	306	262
Operating Segments \| Healthcare Segment
Segment Reporting Information [Line Items]
Income from operations	254	208
Operating Segments \| Products and Resources
Segment Reporting Information [Line Items]
Income from operations	205	181
Operating Segments \| Communications, Media and Technology
Segment Reporting Information [Line Items]
Income from operations	92	90
Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting Information [Line Items]
Unallocated costs	$ 4	$ 46

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