Revenue Recognition - Revenue by Segment, Sales Channel and Product Category (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	$ 4,612	$ 4,924	$ 9,288	$ 9,953
Operating Segments
Disaggregation of Revenue [Line Items]
Total revenue	4,612	4,924	9,288	9,953
Adjustments for non-ASC 606 revenue	(353)	(471)	(768)	(945)
Total revenue from contracts with customers	4,259	4,453	8,520	9,008
Operating Segments | Business
Disaggregation of Revenue [Line Items]
Total revenue	3,416	3,522	6,817	7,117
Adjustments for non-ASC 606 revenue	(273)	(273)	(548)	(547)
Total revenue from contracts with customers	3,143	3,249	6,269	6,570
Operating Segments | Business | Compute and Application Services
Disaggregation of Revenue [Line Items]
Total revenue	453	435	880	866
Adjustments for non-ASC 606 revenue	(132)	(135)	(266)	(267)
Total revenue from contracts with customers	321	300	614	599
Operating Segments | Business | IP and Data Services
Disaggregation of Revenue [Line Items]
Total revenue	1,495	1,549	3,017	3,127
Adjustments for non-ASC 606 revenue	(1)	(2)	(2)	(3)
Total revenue from contracts with customers	1,494	1,547	3,015	3,124
Operating Segments | Business | Fiber Infrastructure
Disaggregation of Revenue [Line Items]
Total revenue	564	552	1,099	1,109
Adjustments for non-ASC 606 revenue	(77)	(74)	(153)	(152)
Total revenue from contracts with customers	487	478	946	957
Operating Segments | Business | Voice and Other
Disaggregation of Revenue [Line Items]
Total revenue	904	986	1,821	2,015
Adjustments for non-ASC 606 revenue	(63)	(62)	(127)	(125)
Total revenue from contracts with customers	841	924	1,694	1,890
Operating Segments | Business | International and Global Accounts ("IGAM")
Disaggregation of Revenue [Line Items]
Total revenue	996	1,011	1,995	2,031
Adjustments for non-ASC 606 revenue	(106)	(102)	(213)	(201)
Total revenue from contracts with customers	890	909	1,782	1,830
Operating Segments | Business | International and Global Accounts ("IGAM") | Compute and Application Services
Disaggregation of Revenue [Line Items]
Total revenue	184	181	367	364
Adjustments for non-ASC 606 revenue	(71)	(70)	(144)	(139)
Total revenue from contracts with customers	113	111	223	225
Operating Segments | Business | International and Global Accounts ("IGAM") | IP and Data Services
Disaggregation of Revenue [Line Items]
Total revenue	417	427	840	856
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	417	427	840	856
Operating Segments | Business | International and Global Accounts ("IGAM") | Fiber Infrastructure
Disaggregation of Revenue [Line Items]
Total revenue	224	217	443	434
Adjustments for non-ASC 606 revenue	(35)	(32)	(69)	(62)
Total revenue from contracts with customers	189	185	374	372
Operating Segments | Business | International and Global Accounts ("IGAM") | Voice and Other
Disaggregation of Revenue [Line Items]
Total revenue	171	186	345	377
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	171	186	345	377
Operating Segments | Business | Large Enterprise
Disaggregation of Revenue [Line Items]
Total revenue	884	945	1,761	1,898
Adjustments for non-ASC 606 revenue	(26)	(27)	(53)	(57)
Total revenue from contracts with customers	858	918	1,708	1,841
Operating Segments | Business | Large Enterprise | Compute and Application Services
Disaggregation of Revenue [Line Items]
Total revenue	162	174	325	343
Adjustments for non-ASC 606 revenue	(15)	(15)	(29)	(30)
Total revenue from contracts with customers	147	159	296	313
Operating Segments | Business | Large Enterprise | IP and Data Services
Disaggregation of Revenue [Line Items]
Total revenue	385	396	773	798
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	385	396	773	798
Operating Segments | Business | Large Enterprise | Fiber Infrastructure
Disaggregation of Revenue [Line Items]
Total revenue	129	130	242	260
Adjustments for non-ASC 606 revenue	(11)	(12)	(24)	(27)
Total revenue from contracts with customers	118	118	218	233
Operating Segments | Business | Large Enterprise | Voice and Other
Disaggregation of Revenue [Line Items]
Total revenue	208	245	421	497
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	208	245	421	497
Operating Segments | Business | Mid-Market Enterprise
Disaggregation of Revenue [Line Items]
Total revenue	626	661	1,262	1,354
Adjustments for non-ASC 606 revenue	(10)	(13)	(20)	(24)
Total revenue from contracts with customers	616	648	1,242	1,330
Operating Segments | Business | Mid-Market Enterprise | Compute and Application Services
Disaggregation of Revenue [Line Items]
Total revenue	34	32	67	64
Adjustments for non-ASC 606 revenue	(7)	(9)	(14)	(17)
Total revenue from contracts with customers	27	23	53	47
Operating Segments | Business | Mid-Market Enterprise | IP and Data Services
Disaggregation of Revenue [Line Items]
Total revenue	408	428	823	870
Adjustments for non-ASC 606 revenue	(1)	(2)	(2)	(3)
Total revenue from contracts with customers	407	426	821	867
Operating Segments | Business | Mid-Market Enterprise | Fiber Infrastructure
Disaggregation of Revenue [Line Items]
Total revenue	50	50	99	106
Adjustments for non-ASC 606 revenue	(2)	(2)	(4)	(4)
Total revenue from contracts with customers	48	48	95	102
Operating Segments | Business | Mid-Market Enterprise | Voice and Other
Disaggregation of Revenue [Line Items]
Total revenue	134	151	273	314
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	134	151	273	314
Operating Segments | Business | Wholesale
Disaggregation of Revenue [Line Items]
Total revenue	910	905	1,799	1,834
Adjustments for non-ASC 606 revenue	(131)	(131)	(262)	(265)
Total revenue from contracts with customers	779	774	1,537	1,569
Operating Segments | Business | Wholesale | Compute and Application Services
Disaggregation of Revenue [Line Items]
Total revenue	73	48	121	95
Adjustments for non-ASC 606 revenue	(39)	(41)	(79)	(81)
Total revenue from contracts with customers	34	7	42	14
Operating Segments | Business | Wholesale | IP and Data Services
Disaggregation of Revenue [Line Items]
Total revenue	285	298	581	603
Adjustments for non-ASC 606 revenue	0	0	0	0
Total revenue from contracts with customers	285	298	581	603
Operating Segments | Business | Wholesale | Fiber Infrastructure
Disaggregation of Revenue [Line Items]
Total revenue	161	155	315	309
Adjustments for non-ASC 606 revenue	(29)	(28)	(56)	(59)
Total revenue from contracts with customers	132	127	259	250
Operating Segments | Business | Wholesale | Voice and Other
Disaggregation of Revenue [Line Items]
Total revenue	391	404	782	827
Adjustments for non-ASC 606 revenue	(63)	(62)	(127)	(125)
Total revenue from contracts with customers	328	342	655	702
Operating Segments | Mass Markets
Disaggregation of Revenue [Line Items]
Total revenue	1,196	1,402	2,471	2,836
Adjustments for non-ASC 606 revenue	(80)	(198)	(220)	(398)
Total revenue from contracts with customers	1,116	1,204	2,251	2,438
Operating Segments | Mass Markets | Fiber Broadband
Disaggregation of Revenue [Line Items]
Total revenue	151	130	296	252
Adjustments for non-ASC 606 revenue	(5)	0	(10)	0
Total revenue from contracts with customers	146	130	286	252
Operating Segments | Mass Markets | Other Broadband
Disaggregation of Revenue [Line Items]
Total revenue	596	632	1,206	1,280
Adjustments for non-ASC 606 revenue	(55)	(55)	(111)	(110)
Total revenue from contracts with customers	541	577	1,095	1,170
Operating Segments | Mass Markets | Voice and Other
Disaggregation of Revenue [Line Items]
Total revenue	449	640	969	1,304
Adjustments for non-ASC 606 revenue	(20)	(143)	(99)	(288)
Total revenue from contracts with customers	$ 429	$ 497	$ 870	$ 1,016