Summary of Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment	$ 1,227	$ 1,109
Less accumulated depreciation	(196)	(10)
Property and equipment, net	1,031	1,099
Depreciation expense	192	9
Capitalized interest costs	2
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 16	16
Building
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	25 years
Property and equipment, gross	$ 98	94
Telephony transmission equipment and distribution facilities
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 705	667
Telephony transmission equipment and distribution facilities | Minimum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	5 years
Telephony transmission equipment and distribution facilities | Maximum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	20 years
Cable transmission equipment and distribution facilities
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 94	84
Cable transmission equipment and distribution facilities | Minimum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	5 years
Cable transmission equipment and distribution facilities | Maximum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	30 years
Support equipment and systems
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 97	86
Support equipment and systems | Minimum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	3 years
Support equipment and systems | Maximum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	20 years
Fiber optic cable systems
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 69	68
Fiber optic cable systems | Minimum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	15 years
Fiber optic cable systems | Maximum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	25 years
Other
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 40	33
Other | Minimum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	2 years
Other | Maximum
Property, Plant and Equipment [Line Items]
Remaining useful lives of property and equipment	20 years
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 108	$ 61