Revenue Recognition - Disaggregation of Revenue by Major Products and Service Offerings (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021		Sep. 30, 2022	Sep. 30, 2021
Revenue by Major Products/Service Offerings
Total Revenue	$ 14,107	$ 13,251	[1]	$ 43,840	$ 40,656	[1]
Business Segments
Revenue by Major Products/Service Offerings
Total Revenue	14,037	12,969		43,365	39,812
Other
Revenue by Major Products/Service Offerings
Revenue	70	282		475	844
Software | Business Segments
Revenue by Major Products/Service Offerings
Revenue	5,811	5,406		17,749	16,339
Total Revenue	5,811	5,406		17,749	16,339
Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	4,700	4,457		14,337	13,098
Total Revenue	4,700	4,457		14,337	13,098
Infrastructure | Business Segments
Revenue by Major Products/Service Offerings
Revenue	3,352	2,921		10,805	9,774
Total Revenue	3,352	2,921		10,805	9,774
Financing | Business Segments
Revenue by Major Products/Service Offerings
Revenue	174	184		474	601
Total Revenue	174	184		474	601
Hybrid Platform & Solutions | Software | Business Segments
Revenue by Major Products/Service Offerings
Revenue	4,172	4,074		12,641	12,082
Transaction Processing | Software | Business Segments
Revenue by Major Products/Service Offerings
Revenue	1,640	1,332		5,107	4,257
Business Transformation | Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	2,165	2,068		6,646	6,070
Technology Consulting | Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	943	889		2,826	2,538
Application Operations | Consulting | Business Segments
Revenue by Major Products/Service Offerings
Revenue	1,593	1,501		4,865	4,489
Hybrid Infrastructure | Infrastructure | Business Segments
Revenue by Major Products/Service Offerings
Revenue	1,931	1,453		6,392	5,294
Infrastructure Support | Infrastructure | Business Segments
Revenue by Major Products/Service Offerings
Revenue	$ 1,421	$ 1,468		$ 4,413	$ 4,480

[1] Reclassified to reflect discontinued operations presentation.