Goodwill, Customer Relationships and Other Intangible Assets - Rollforward Goodwill (Details) - USD ($)					3 Months Ended	12 Months Ended
	Oct. 31, 2023	Oct. 31, 2021	Jul. 31, 2021	Jan. 31, 2021	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill Activity
As of beginning of period						$ 12,657,000,000	$ 15,986,000,000
Effect of foreign currency exchange rate change and other							(58,000,000)
Impairment	$ (1,900,000,000)	$ 0	$ 0	$ 0	$ (8,800,000,000)	(10,693,000,000)	(3,271,000,000)	$ 0
As of end of period						1,964,000,000	12,657,000,000	15,986,000,000
Goodwill accumulated impairment loss						21,700,000,000	11,000,000,000	7,700,000,000
Business
Goodwill Activity
As of beginning of period						7,906,000,000	11,235,000,000
Effect of foreign currency exchange rate change and other							(58,000,000)
Impairment						(7,906,000,000)	(3,271,000,000)
As of end of period						0	7,906,000,000	11,235,000,000
Mass Markets
Goodwill Activity
As of beginning of period						4,751,000,000	4,751,000,000
Effect of foreign currency exchange rate change and other							0
Impairment						(2,787,000,000)
As of end of period						$ 1,964,000,000	$ 4,751,000,000	$ 4,751,000,000