Segment Information (Revenues From External Customers And Segment Operating Profit) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Income from operations	$ 817	$ 708	$ 1,670	$ 1,403
Revenue	5,245	4,850	10,360	9,610
Other Segment Items	4,386	4,100	8,644	8,119
Financial Services
Segment Reporting Information [Line Items]
Revenue	1,547	1,447	3,009	2,832
Other Segment Items	1,293	1,239	2,501	2,416
Healthcare Segment
Segment Reporting Information [Line Items]
Revenue	1,551	1,461	3,122	2,877
Other Segment Items	1,248	1,187	2,513	2,341
Products and Resources
Segment Reporting Information [Line Items]
Revenue	1,306	1,126	2,584	2,259
Other Segment Items	1,119	947	2,192	1,899
Communication, Media and Technology
Segment Reporting Information [Line Items]
Revenue	841	816	1,645	1,642
Other Segment Items	726	727	1,438	1,463
Operating Segments
Segment Reporting Information [Line Items]
Income from operations	859	750	1,716	1,491
Operating Segments \| Financial Services
Segment Reporting Information [Line Items]
Income from operations	303	274	609	536
Operating Segments \| Healthcare Segment
Segment Reporting Information [Line Items]
Income from operations	254	208	508	416
Operating Segments \| Products and Resources
Segment Reporting Information [Line Items]
Income from operations	187	179	392	360
Operating Segments \| Communications, Media and Technology
Segment Reporting Information [Line Items]
Income from operations	115	89	207	179
Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting Information [Line Items]
Unallocated costs	$ 42	$ 42	$ 46	$ 88

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