Debt - Credit Facilities, Non-Cash Transaction, Guarantees (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Debt Instrument [Line Items]
Facility Capacity	$ 20,500,000,000		$ 20,500,000,000
Unused Capacity	9,941,000,000		9,941,000,000
Principal Amount Outstanding	6,720,000,000		6,720,000,000
Debt extinguishment gains (losses)	69,000,000	$ 50,000,000	139,000,000	$ (1,200,000,000)
Guarantee of Debentures of Operating Telephone Company Subsidiaries
Debt Instrument [Line Items]
Principal amount outstanding in connection with the guarantee of debt obligations	614,000,000		614,000,000
Network Equipment | Alternative Financing Facility
Debt Instrument [Line Items]
Value of purchase assets financed			719,000,000	321,000,000
Long-term debt maturing within one year	2,200,000,000		2,200,000,000		$ 1,700,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Facility Capacity	9,500,000,000		9,500,000,000
Unused Capacity	9,455,000,000		9,455,000,000
Principal Amount Outstanding	0		0
Amount drawn from credit facilities			0
Equipment Credit Facilities
Debt Instrument [Line Items]
Facility Capacity	11,000,000,000		11,000,000,000
Unused Capacity	486,000,000		486,000,000
Principal Amount Outstanding	$ 6,720,000,000		6,720,000,000
Amount drawn from credit facilities			$ 515,000,000	$ 2,000,000,000