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 revenues	$ 1,953	$ 1,985	$ 3,899	$ 3,974
Adjustments for non-ASC 606 revenue	(244)	(241)	(486)	(478)
Total revenue from contracts with customers	1,709	1,744	3,413	3,496
Compute and Application Services
Disaggregation of Revenue [Line Items]
Total revenues	283	283	560	563
Adjustments for non-ASC 606 revenue	(126)	(127)	(254)	(254)
Total revenue from contracts with customers	157	156	306	309
IP and Data Services
Disaggregation of Revenue [Line Items]
Total revenues	883	888	1,769	1,769
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	883	888	1,769	1,769
Fiber Infrastructure Services
Disaggregation of Revenue [Line Items]
Total revenues	403	401	794	798
Adjustments for non-ASC 606 revenue	(57)	(55)	(111)	(108)
Total revenue from contracts with customers	346	346	683	690
Voice and Other
Disaggregation of Revenue [Line Items]
Total revenues	327	357	663	733
Adjustments for non-ASC 606 revenue	(4)	(3)	(8)	(5)
Total revenue from contracts with customers	323	354	655	728
Affiliate Services
Disaggregation of Revenue [Line Items]
Total revenues	57	56	113	111
Adjustments for non-ASC 606 revenue	(57)	(56)	(113)	(111)
Total revenue from contracts with customers	$ 0	$ 0	$ 0	$ 0