Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Disaggregation of Revenue [Line Items]
Total Revenue	$ 1,632	$ 1,724	$ 3,288	$ 3,516
Adjustments for non-ASC 606 revenue	(92)	(118)	(196)	(237)
Total Revenue from Contracts with Customers	1,540	1,606	3,092	3,279
Fiber Infrastructure [Member]
Disaggregation of Revenue [Line Items]
Total Revenue	496	501	994	1,005
Adjustments for non-ASC 606 revenue	(33)	(29)	(67)	(60)
Total Revenue from Contracts with Customers	463	472	927	945
Voice and Other [Member]
Disaggregation of Revenue [Line Items]
Total Revenue	442	530	902	1,073
Adjustments for non-ASC 606 revenue	(47)	(83)	(106)	(168)
Total Revenue from Contracts with Customers	395	447	796	905
IP & Data Services [Member]
Disaggregation of Revenue [Line Items]
Total Revenue	111	116	228	239
Adjustments for non-ASC 606 revenue	0	0	0	0
Total Revenue from Contracts with Customers	111	116	228	239
Affiliate Services [Member]
Disaggregation of Revenue [Line Items]
Total Revenue	583	577	1,164	1,199
Adjustments for non-ASC 606 revenue	(12)	(6)	(23)	(9)
Total Revenue from Contracts with Customers	$ 571	$ 571	$ 1,141	$ 1,190