Goodwill, Customer Relationships and Other Intangible Assets - Schedule of Goodwill, Customer Relationships, and Other Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Goodwill	$ 15,976	$ 15,986
Indefinite-life intangible assets	9	9
Total other intangible assets, net	6,785	6,970
Customer relationships
Goodwill [Line Items]
Finite-lived intangible assets, net	5,180	5,365
Accumulated amortization	3,268	11,740
Capitalized software
Goodwill [Line Items]
Finite-lived intangible assets, net	1,469	1,459
Accumulated amortization	3,656	3,624
Trade names, patents and other
Goodwill [Line Items]
Finite-lived intangible assets, net	127	137
Accumulated amortization	162	$ 160
Fully amortized and retired customer relationships
Goodwill [Line Items]
Gross carrying value	$ 8,700