Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue	$ 7,952	$ 7,933	$ 7,773
Adjustments for Non-ASC 606 Revenue	(959)	(919)	(893)
Total Revenue from Contracts with Customers	6,993	7,014	6,880
Transferred at Point in Time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue from Contracts with Customers	13	15	0
Transferred over Time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue from Contracts with Customers	6,980	6,999	6,880
Compute and Application Services
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue	1,141	1,098	1,063
Adjustments for Non-ASC 606 Revenue	(504)	(494)	(506)
Total Revenue from Contracts with Customers	637	604	557
IP and Data Services
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue	3,555	3,522	3,528
Adjustments for Non-ASC 606 Revenue	0	0	0
Total Revenue from Contracts with Customers	3,555	3,522	3,528
Fiber Infrastructure Services
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue	1,612	1,507	1,392
Adjustments for Non-ASC 606 Revenue	(220)	(209)	(198)
Total Revenue from Contracts with Customers	1,392	1,298	1,194
Voice and Other
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue	1,421	1,598	1,610
Adjustments for Non-ASC 606 Revenue	(12)	(8)	(9)
Total Revenue from Contracts with Customers	1,409	1,590	1,601
Affiliate Services
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue	223	208	180
Adjustments for Non-ASC 606 Revenue	(223)	(208)	(180)
Total Revenue from Contracts with Customers	$ 0	$ 0	$ 0