Goodwill, Customer Relationships and Other Intangible Assets - Schedule of Goodwill, Customer Relationships, and Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 3,864			$ 3,864		$ 12,657
Indefinite-lived intangible assets	9			9		9
Total other intangible assets, net	5,744			5,744		6,166
Goodwill impairment	0	$ 8,800	$ 0	8,793	$ 0
Customer Relationships
Goodwill And Intangible Assets [Line Items]
Other intangible assets subject to amortization	4,088			4,088		4,574
Accumulated amortization	4,087			4,087		3,606
Capitalized Software
Goodwill And Intangible Assets [Line Items]
Other intangible assets subject to amortization	1,557			1,557		1,482
Accumulated amortization	3,961			3,961		3,895
Trade Names, Patents and Other
Goodwill And Intangible Assets [Line Items]
Other intangible assets subject to amortization	90			90		101
Accumulated amortization	$ 68			$ 68		188
Fully Amortized and Retired Capitalized Software
Goodwill And Intangible Assets [Line Items]
Gross carrying value						183
Fully Amortized and Retired Trade Names
Goodwill And Intangible Assets [Line Items]
Gross carrying value						$ 130