Property, Plant And Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 350,914	$ 339,891
Accumulated depreciation and amortization	222,043	211,402
Property, plant and equipment – net	128,871	128,489	$ 127,445
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	1,372	1,377
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 39,947	39,380
Buildings and improvements | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Buildings and improvements | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	44 years
Central office equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 101,607	100,264
Central office equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Central office equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Cable, wiring and conduit
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 95,217	90,109
Cable, wiring and conduit | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	15 years
Cable, wiring and conduit | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	50 years
Other equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 87,656	85,379
Other equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Other equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 17,663	17,742
Software | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Software | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years
Under construction
Property, Plant and Equipment [Line Items]
Property, plant and equipment, at cost	$ 7,452	$ 5,640