Revenue Recognition - Revenue by Segment, Sales Channel and Product Category (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Total Revenue	$ 3,221	$ 3,641	$ 9,779	$ 11,040
Adjustments for non-ASC 606 revenue	(254)	(262)	(733)	(804)
Total revenue from Contracts with Customers	2,967	3,379	9,046	10,236
Business
Disaggregation of Revenue [Line Items]
Total Revenue	2,536	2,905	7,704	8,781
Mass Markets
Disaggregation of Revenue [Line Items]
Total Revenue	685	736	2,075	2,259
Operating Segments | Business
Disaggregation of Revenue [Line Items]
Total Revenue	2,536	2,905	7,704	8,781
Adjustments for non-ASC 606 revenue	(221)	(218)	(620)	(669)
Total revenue from Contracts with Customers	2,315	2,687	7,084	8,112
Operating Segments | Mass Markets
Disaggregation of Revenue [Line Items]
Total Revenue	685	736	2,075	2,259
Adjustments for non-ASC 606 revenue	(33)	(44)	(113)	(135)
Total revenue from Contracts with Customers	652	692	1,962	2,124
Operating Segments | Large Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	839	914	2,534	2,724
Adjustments for non-ASC 606 revenue	(73)	(51)	(184)	(150)
Total revenue from Contracts with Customers	766	863	2,350	2,574
Operating Segments | Mid-Market Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	471	506	1,435	1,543
Adjustments for non-ASC 606 revenue	(11)	(8)	(27)	(28)
Total revenue from Contracts with Customers	460	498	1,408	1,515
Operating Segments | Public Sector | Business
Disaggregation of Revenue [Line Items]
Total Revenue	427	445	1,295	1,292
Adjustments for non-ASC 606 revenue	(22)	(22)	(65)	(60)
Total revenue from Contracts with Customers	405	423	1,230	1,232
Operating Segments | Wholesale | Business
Disaggregation of Revenue [Line Items]
Total Revenue	706	776	2,159	2,402
Adjustments for non-ASC 606 revenue	(114)	(108)	(341)	(342)
Total revenue from Contracts with Customers	592	668	1,818	2,060
Operating Segments | International and Other | Business
Disaggregation of Revenue [Line Items]
Total Revenue	93	264	281	820
Adjustments for non-ASC 606 revenue	(1)	(29)	(3)	(89)
Total revenue from Contracts with Customers	92	235	278	731
Operating Segments | Grow | Business
Disaggregation of Revenue [Line Items]
Total Revenue	1,076	1,131	3,198	3,409
Adjustments for non-ASC 606 revenue	(174)	(166)	(478)	(509)
Total revenue from Contracts with Customers	902	965	2,720	2,900
Operating Segments | Grow | Large Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	436	429	1,287	1,278
Adjustments for non-ASC 606 revenue	(73)	(48)	(183)	(145)
Total revenue from Contracts with Customers	363	381	1,104	1,133
Operating Segments | Grow | Mid-Market Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	211	201	628	601
Adjustments for non-ASC 606 revenue	(6)	(6)	(19)	(21)
Total revenue from Contracts with Customers	205	195	609	580
Operating Segments | Grow | Public Sector | Business
Disaggregation of Revenue [Line Items]
Total Revenue	131	118	383	354
Adjustments for non-ASC 606 revenue	(21)	(22)	(62)	(60)
Total revenue from Contracts with Customers	110	96	321	294
Operating Segments | Grow | Wholesale | Business
Disaggregation of Revenue [Line Items]
Total Revenue	259	256	783	792
Adjustments for non-ASC 606 revenue	(73)	(61)	(211)	(194)
Total revenue from Contracts with Customers	186	195	572	598
Operating Segments | Grow | International and Other | Business
Disaggregation of Revenue [Line Items]
Total Revenue	39	127	117	384
Adjustments for non-ASC 606 revenue	(1)	(29)	(3)	(89)
Total revenue from Contracts with Customers	38	98	114	295
Operating Segments | Nurture | Business
Disaggregation of Revenue [Line Items]
Total Revenue	729	874	2,257	2,661
Adjustments for non-ASC 606 revenue	(6)	(5)	(20)	(19)
Total revenue from Contracts with Customers	723	869	2,237	2,642
Operating Segments | Nurture | Large Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	253	297	779	890
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	253	297	779	890
Operating Segments | Nurture | Mid-Market Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	167	203	533	632
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	167	203	533	632
Operating Segments | Nurture | Public Sector | Business
Disaggregation of Revenue [Line Items]
Total Revenue	87	98	262	298
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	87	98	262	298
Operating Segments | Nurture | Wholesale | Business
Disaggregation of Revenue [Line Items]
Total Revenue	183	206	562	627
Adjustments for non-ASC 606 revenue	(6)	(5)	(20)	(19)
Total revenue from Contracts with Customers	177	201	542	608
Operating Segments | Nurture | International and Other | Business
Disaggregation of Revenue [Line Items]
Total Revenue	39	70	121	214
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	39	70	121	214
Operating Segments | Harvest | Business
Disaggregation of Revenue [Line Items]
Total Revenue	549	662	1,697	2,059
Adjustments for non-ASC 606 revenue	(37)	(43)	(116)	(132)
Total revenue from Contracts with Customers	512	619	1,581	1,927
Operating Segments | Harvest | Large Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	106	131	337	403
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	106	131	337	403
Operating Segments | Harvest | Mid-Market Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	83	93	248	283
Adjustments for non-ASC 606 revenue	(1)	(1)	(3)	(3)
Total revenue from Contracts with Customers	82	92	245	280
Operating Segments | Harvest | Public Sector | Business
Disaggregation of Revenue [Line Items]
Total Revenue	86	96	272	290
Adjustments for non-ASC 606 revenue	(1)	0	(3)	0
Total revenue from Contracts with Customers	85	96	269	290
Operating Segments | Harvest | Wholesale | Business
Disaggregation of Revenue [Line Items]
Total Revenue	261	312	807	974
Adjustments for non-ASC 606 revenue	(35)	(42)	(110)	(129)
Total revenue from Contracts with Customers	226	270	697	845
Operating Segments | Harvest | International and Other | Business
Disaggregation of Revenue [Line Items]
Total Revenue	13	30	33	109
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	13	30	33	109
Operating Segments | Other | Business
Disaggregation of Revenue [Line Items]
Total Revenue	182	238	552	652
Adjustments for non-ASC 606 revenue	(4)	(4)	(6)	(9)
Total revenue from Contracts with Customers	178	234	546	643
Operating Segments | Other | Large Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	44	57	131	153
Adjustments for non-ASC 606 revenue	0	(3)	(1)	(5)
Total revenue from Contracts with Customers	44	54	130	148
Operating Segments | Other | Mid-Market Enterprise | Business
Disaggregation of Revenue [Line Items]
Total Revenue	10	9	26	27
Adjustments for non-ASC 606 revenue	(4)	(1)	(5)	(4)
Total revenue from Contracts with Customers	6	8	21	23
Operating Segments | Other | Public Sector | Business
Disaggregation of Revenue [Line Items]
Total Revenue	123	133	378	350
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	123	133	378	350
Operating Segments | Other | Wholesale | Business
Disaggregation of Revenue [Line Items]
Total Revenue	3	2	7	9
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	3	2	7	9
Operating Segments | Other | International and Other | Business
Disaggregation of Revenue [Line Items]
Total Revenue	2	37	10	113
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from Contracts with Customers	2	37	10	113
Operating Segments | Fiber Broadband | Mass Markets
Disaggregation of Revenue [Line Items]
Total Revenue	190	163	541	473
Adjustments for non-ASC 606 revenue	(3)	(4)	(10)	(12)
Total revenue from Contracts with Customers	187	159	531	461
Operating Segments | Other Broadband | Mass Markets
Disaggregation of Revenue [Line Items]
Total Revenue	282	341	895	1,065
Adjustments for non-ASC 606 revenue	(25)	(31)	(80)	(96)
Total revenue from Contracts with Customers	257	310	815	969
Operating Segments | Voice and Other | Mass Markets
Disaggregation of Revenue [Line Items]
Total Revenue	213	232	639	721
Adjustments for non-ASC 606 revenue	(5)	(9)	(23)	(27)
Total revenue from Contracts with Customers	$ 208	$ 223	$ 616	$ 694