Property, Plant and Equipment - Net Property, Plant and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment, Net [Abstract]
Gross property, plant and equipment	$ 11,693	$ 11,063
Accumulated depreciation	(4,139)	(3,665)
Net property, plant and equipment	7,554	7,398
Land
Property, Plant and Equipment, Net [Abstract]
Gross property, plant and equipment	191	202
Fiber conduit and other outside plant
Property, Plant and Equipment, Net [Abstract]
Gross property, plant and equipment	$ 4,563	4,380
Fiber conduit and other outside plant | Minimum
Property, Plant and Equipment [Line Items]
Depreciable Lives	15 years
Fiber conduit and other outside plant | Maximum
Property, Plant and Equipment [Line Items]
Depreciable Lives	45 years
Central office and other network electronics
Property, Plant and Equipment, Net [Abstract]
Gross property, plant and equipment	$ 3,752	3,467
Central office and other network electronics | Minimum
Property, Plant and Equipment [Line Items]
Depreciable Lives	7 years
Central office and other network electronics | Maximum
Property, Plant and Equipment [Line Items]
Depreciable Lives	10 years
Support assets
Property, Plant and Equipment, Net [Abstract]
Gross property, plant and equipment	$ 2,278	2,252
Support assets | Minimum
Property, Plant and Equipment [Line Items]
Depreciable Lives	3 years
Support assets | Maximum
Property, Plant and Equipment [Line Items]
Depreciable Lives	30 years
Construction-in-progress
Property, Plant and Equipment, Net [Abstract]
Gross property, plant and equipment	$ 909	$ 762