Goodwill, Customer Relationships and Other Intangible Assets - Schedule of Goodwill and Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2021	Jan. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 15,986	$ 0	$ 18,870	$ 21,534
Indefinite-lived intangible assets	9		278
Total other intangible assets, net	6,970		8,219
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	5,365		6,344
Accumulated amortization	11,740		11,060
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	1,459		1,520
Accumulated amortization	3,624		3,279
Trade names, patents and other
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	137		77
Accumulated amortization	$ 160		$ 120