Revenue Recognition - Disaggregation of Revenue by Major Products and Service Offerings (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue by Major Products/Service Offerings
Total Revenue	$ 14,462	$ 14,252
Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	14,354	14,083
Other
Revenue by Major Products/Service Offerings
Revenue	108	169
Software | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	5,899	5,591
Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	5,186	5,197
Infrastructure | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	3,076	3,098
Financing | Operating Segments
Revenue by Major Products/Service Offerings
Total Revenue	193	196
Hybrid Platform & Solutions | Software | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	4,098	3,850
Transaction Processing | Software | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	1,800	1,742
Business Transformation | Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	2,317	2,283
Application Operations | Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	1,938	1,989
Technology Consulting | Consulting | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	931	925
Hybrid Infrastructure | Infrastructure | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	1,803	1,709
Infrastructure Support | Infrastructure | Operating Segments
Revenue by Major Products/Service Offerings
Revenue	$ 1,273	$ 1,389