Revenue Recognition (Disaggregation Of Revenue) (Details) - USD ($) $ in Millions	4 Months Ended	8 Months Ended	12 Months Ended
	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 2,120	$ 3,958	$ 5,733	$ 6,781
Subsidy and other revenue	111	222	54	374
Total revenue	2,231	4,180	5,787	7,155
Data And Internet Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,125	2,224	3,390	3,478
Voice Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	647	1,091	1,498	2,085
Video Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	223	397	520	789
Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	125	246	325	429
Consumer [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,133	2,125	3,116	3,609
Business And Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 987	$ 1,833	$ 2,617	$ 3,172