Goodwill, Customer Relationships and Other Intangible Assets - Reconciliation of Goodwill (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
	Oct. 31, 2022	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Goodwill
As of December 31, 2022					$ 1,970
Impairment	$ (2,000)	$ (1,970)		$ 0	(1,970)	$ 0
As of June 30, 2023		0	$ 1,970		0
Accumulated impairment losses		$ 10,200	$ 8,200		$ 10,200