Revenue Recognition - Disaggregation of Revenue by Major Products and Service Offerings (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021		Jun. 30, 2022	Jun. 30, 2021
Revenue by Major Products/Service Offerings
Total Revenue	$ 15,535	$ 14,218	[1]	$ 29,732	$ 27,405	[1]
Business Segments
Revenue by Major Products/Service Offerings
Total Revenue	15,355	13,941		29,328	26,843
Other
Revenue by Major Products/Service Offerings
Revenue	180	277		404	561
Software | Business Segments
Revenue by Major Products/Service Offerings
Revenue	6,166	5,795		11,938	10,933
Total Revenue	6,166	5,795		11,938	10,933
Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	4,809	4,378		9,637	8,641
Total Revenue	4,809	4,378		9,637	8,641
Infrastructure | Business Segments
Revenue by Major Products/Service Offerings
Revenue	4,235	3,560		7,453	6,853
Total Revenue	4,235	3,560		7,453	6,853
Financing | Business Segments
Revenue by Major Products/Service Offerings
Revenue	146	209		300	417
Total Revenue	146	209		300	417
Hybrid Platform & Solutions | Software | Business Segments
Revenue by Major Products/Service Offerings
Revenue	4,390	4,208		8,470	8,008
Transaction Processing | Software | Business Segments
Revenue by Major Products/Service Offerings
Revenue	1,776	1,587		3,468	2,925
Business Transformation | Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	2,227	2,049		4,482	4,002
Technology Consulting | Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	928	814		1,884	1,649
Application Operations | Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	1,653	1,514		3,272	2,989
Hybrid Infrastructure | Infrastructure | Business Segments
Revenue by Major Products/Service Offerings
Revenue	2,760	2,059		4,461	3,841
Infrastructure Support | Infrastructure | Business Segments
Revenue by Major Products/Service Offerings
Revenue	$ 1,474	$ 1,501		$ 2,993	$ 3,012

[1] Reclassified to reflect discontinued operations presentation.