Goodwill, Customer Relationships and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 0	$ 1,970
Other intangible assets, net	4,675	4,973
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, net	4,246	4,563
Accumulated amortization	3,579	3,265
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, net	429	410
Accumulated amortization	376	387
Trade names
Finite-Lived Intangible Assets [Line Items]
Other intangible assets, net	0	0
Accumulated amortization	0	$ 130
Fully Amortized and Retired Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of intangibles fully amortized and retired	$ 130