Revenue Recognition - Disaggregation of Revenue by Major Products and Service Offerings (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenue by Major Products/Service Offerings
Total Revenue	$ 15,770	$ 15,475	$ 30,231	$ 29,727
Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	15,732	15,322	30,085	29,406
Other
Revenue by Major Products/Service Offerings
Revenue	38	152	146	321
Software | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	6,739	6,294	12,637	11,885
Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	5,179	5,226	10,365	10,423
Infrastructure | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	3,645	3,618	6,721	6,716
Financing | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	169	185	362	380
Hybrid Platform & Solutions | Software | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	4,575	4,350	8,673	8,200
Transaction Processing | Software | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	2,164	1,943	3,964	3,685
Business Transformation | Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	2,360	2,295	4,677	4,578
Application Operations | Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	1,902	1,991	3,840	3,980
Technology Consulting | Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	917	941	1,848	1,866
Hybrid Infrastructure | Infrastructure | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	2,360	2,260	4,163	3,969
Infrastructure Support | Infrastructure | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	$ 1,285	$ 1,358	$ 2,558	$ 2,747