Credit Losses on Financial Instruments - Finance Receivable, Allowance for Credit Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss
Beginning balance	$ 36	$ 38	$ 61
Provision for expected losses	66	60	27
Write-offs charged against the allowance	(69)	(64)	(54)
Recoveries collected	1	2	4
Ending balance	34	36	38
Business
Financing Receivable, Allowance for Credit Loss
Beginning balance	20	19	25
Provision for expected losses	20	13	10
Write-offs charged against the allowance	(26)	(14)	(19)
Recoveries collected	0	2	3
Ending balance	14	20	19
Mass Markets
Financing Receivable, Allowance for Credit Loss
Beginning balance	16	19	36
Provision for expected losses	46	47	17
Write-offs charged against the allowance	(43)	(50)	(35)
Recoveries collected	1	0	1
Ending balance	$ 20	$ 16	$ 19