Segment Information - Segment Results and Operating Revenue (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Operating revenues by products and services
Revenues	[1]	$ 5,228	$ 5,427
Cost of services and products	[1]	2,235	2,300
Selling, general and administrative		853	932
Less: share-based compensation		(69)	(33)
Total expense		3,019	3,199
Total adjusted EBITDA		2,209	2,228
IP and Data Services
Operating revenues by products and services
Revenues		1,624	1,660
Transport and Infrastructure
Operating revenues by products and services
Revenues		1,232	1,246
Voice and Collaboration
Operating revenues by products and services
Revenues		920	967
IT and Managed Services
Operating revenues by products and services
Revenues		125	145
Broadband
Operating revenues by products and services
Revenues		722	722
Voice
Operating revenues by products and services
Revenues		421	477
Regulatory
Operating revenues by products and services
Revenues		156	157
Other
Operating revenues by products and services
Revenues		28	53
Operating segments
Operating revenues by products and services
Revenues		5,228	5,427
Cost of services and products		957	956
Selling, general and administrative		443	497
Less: share-based compensation		0	0
Total expense		1,400	1,453
Total adjusted EBITDA		3,828	3,974
Operating segments | IP and Data Services
Operating revenues by products and services
Revenues		1,624	1,660
Operating segments | Transport and Infrastructure
Operating revenues by products and services
Revenues		1,232	1,246
Operating segments | Voice and Collaboration
Operating revenues by products and services
Revenues		920	967
Operating segments | IT and Managed Services
Operating revenues by products and services
Revenues		125	145
Operating segments | Broadband
Operating revenues by products and services
Revenues		722	722
Operating segments | Voice
Operating revenues by products and services
Revenues		421	477
Operating segments | Regulatory
Operating revenues by products and services
Revenues		156	157
Operating segments | Other
Operating revenues by products and services
Revenues		28	53
Operating segments | International and Global Accounts
Operating revenues by products and services
Revenues		865	863
Cost of services and products		233	231
Selling, general and administrative		65	67
Less: share-based compensation		0	0
Total expense		298	298
Total adjusted EBITDA		567	565
Operating segments | International and Global Accounts | IP and Data Services
Operating revenues by products and services
Revenues		400	408
Operating segments | International and Global Accounts | Transport and Infrastructure
Operating revenues by products and services
Revenues		316	309
Operating segments | International and Global Accounts | Voice and Collaboration
Operating revenues by products and services
Revenues		91	89
Operating segments | International and Global Accounts | IT and Managed Services
Operating revenues by products and services
Revenues		58	57
Operating segments | International and Global Accounts | Broadband
Operating revenues by products and services
Revenues		0	0
Operating segments | International and Global Accounts | Voice
Operating revenues by products and services
Revenues		0	0
Operating segments | International and Global Accounts | Regulatory
Operating revenues by products and services
Revenues		0	0
Operating segments | International and Global Accounts | Other
Operating revenues by products and services
Revenues		0	0
Operating segments | Enterprise
Operating revenues by products and services
Revenues		1,420	1,425
Cost of services and products		447	428
Selling, general and administrative		136	148
Less: share-based compensation		0
Total expense		583	576
Total adjusted EBITDA		837	849
Operating segments | Enterprise | IP and Data Services
Operating revenues by products and services
Revenues		628	638
Operating segments | Enterprise | Transport and Infrastructure
Operating revenues by products and services
Revenues		380	347
Operating segments | Enterprise | Voice and Collaboration
Operating revenues by products and services
Revenues		356	366
Operating segments | Enterprise | IT and Managed Services
Operating revenues by products and services
Revenues		56	74
Operating segments | Enterprise | Broadband
Operating revenues by products and services
Revenues		0	0
Operating segments | Enterprise | Voice
Operating revenues by products and services
Revenues		0	0
Operating segments | Enterprise | Regulatory
Operating revenues by products and services
Revenues		0	0
Operating segments | Enterprise | Other
Operating revenues by products and services
Revenues		0	0
Operating segments | Small and Medium Business
Operating revenues by products and services
Revenues		658	700
Cost of services and products		104	105
Selling, general and administrative		110	124
Less: share-based compensation		0
Total expense		214	229
Total adjusted EBITDA		444	471
Operating segments | Small and Medium Business | IP and Data Services
Operating revenues by products and services
Revenues		269	276
Operating segments | Small and Medium Business | Transport and Infrastructure
Operating revenues by products and services
Revenues		89	95
Operating segments | Small and Medium Business | Voice and Collaboration
Operating revenues by products and services
Revenues		290	317
Operating segments | Small and Medium Business | IT and Managed Services
Operating revenues by products and services
Revenues		10	12
Operating segments | Small and Medium Business | Broadband
Operating revenues by products and services
Revenues		0	0
Operating segments | Small and Medium Business | Voice
Operating revenues by products and services
Revenues		0	0
Operating segments | Small and Medium Business | Regulatory
Operating revenues by products and services
Revenues		0	0
Operating segments | Small and Medium Business | Other
Operating revenues by products and services
Revenues		0	0
Operating segments | Wholesale
Operating revenues by products and services
Revenues		958	1,030
Cost of services and products		131	134
Selling, general and administrative		17	14
Less: share-based compensation		0
Total expense		148	148
Total adjusted EBITDA		810	882
Operating segments | Wholesale | IP and Data Services
Operating revenues by products and services
Revenues		327	338
Operating segments | Wholesale | Transport and Infrastructure
Operating revenues by products and services
Revenues		447	495
Operating segments | Wholesale | Voice and Collaboration
Operating revenues by products and services
Revenues		183	195
Operating segments | Wholesale | IT and Managed Services
Operating revenues by products and services
Revenues		1	2
Operating segments | Wholesale | Broadband
Operating revenues by products and services
Revenues		0	0
Operating segments | Wholesale | Voice
Operating revenues by products and services
Revenues		0	0
Operating segments | Wholesale | Regulatory
Operating revenues by products and services
Revenues		0	0
Operating segments | Wholesale | Other
Operating revenues by products and services
Revenues		0	0
Operating segments | Consumer
Operating revenues by products and services
Revenues		1,327	1,409
Cost of services and products		42	58
Selling, general and administrative		115	144
Less: share-based compensation		0
Total expense		157	202
Total adjusted EBITDA		1,170	1,207
Operating segments | Consumer | IP and Data Services
Operating revenues by products and services
Revenues		0	0
Operating segments | Consumer | Transport and Infrastructure
Operating revenues by products and services
Revenues		0	0
Operating segments | Consumer | Voice and Collaboration
Operating revenues by products and services
Revenues		0	0
Operating segments | Consumer | IT and Managed Services
Operating revenues by products and services
Revenues		0	0
Operating segments | Consumer | Broadband
Operating revenues by products and services
Revenues		722	722
Operating segments | Consumer | Voice
Operating revenues by products and services
Revenues		421	477
Operating segments | Consumer | Regulatory
Operating revenues by products and services
Revenues		156	157
Operating segments | Consumer | Other
Operating revenues by products and services
Revenues		28	53
Operations and Other
Operating revenues by products and services
Revenues		0	0
Cost of services and products		1,278	1,344
Selling, general and administrative		410	435
Less: share-based compensation		(69)	(33)
Total expense		1,619	1,746
Total adjusted EBITDA		(1,619)	(1,746)
Operations and Other | IP and Data Services
Operating revenues by products and services
Revenues		0	0
Operations and Other | Transport and Infrastructure
Operating revenues by products and services
Revenues		0	0
Operations and Other | Voice and Collaboration
Operating revenues by products and services
Revenues		0	0
Operations and Other | IT and Managed Services
Operating revenues by products and services
Revenues		0	0
Operations and Other | Broadband
Operating revenues by products and services
Revenues		0	0
Operations and Other | Voice
Operating revenues by products and services
Revenues		0	0
Operations and Other | Regulatory
Operating revenues by products and services
Revenues		0	0
Operations and Other | Other
Operating revenues by products and services
Revenues		$ 0	$ 0

[1] Reclassifications were made within certain 2019 comparative figures due to the retrospective application of an accounting policy election during the first quarter of 2020. Refer to Note 1 - Background and our Form 8-K filing dated April 30, 2020 for further information.