Additional Financial Information - Schedule of Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Supplemental Financial Statement Elements [Abstract]
Accounts payable	$ 5,573	$ 7,213
Payroll and related benefits	1,142	1,236
Property and other taxes, including payroll	1,704	1,657
Accrued interest	818	731
Commissions and contract termination costs	317	523
Toll and interconnect	161	227
Other	658	688
Accounts payable and accrued liabilities	10,373	12,275
Accounts Payable and Accrued Liabilities
Accounts Payable and Accrued Liabilities [Line Items]
Outstanding checks	$ 740	$ 720