Revenue Recognition - Disaggregation Of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 4,076	$ 4,039	$ 3,960
Out-of-period adjustment
Disaggregation of Revenue [Line Items]
Immaterial error correction		During the third quarter of 2021, UScellular recorded a $9 million out-of-period error related to the timing of recognition of regulatory fee billings. This adjustment had the impact of increasing Service revenue by $9 million in 2021. UScellular determined that this adjustment was not material to any of the periods impacted.
Transferred over time
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,032	$ 3,032	2,990
Transferred over time | Retail service
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,793	2,757	2,681
Transferred over time | Retail service | Out-of-period adjustment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers		9
Transferred over time | Retail service | Revision of Prior Period, Reclassification, Adjustment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers		(8)	(5)
Transferred over time | Inbound roaming
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	67	110	152
Transferred over time | Other service
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	172	165	157
Transferred over time | Other service | Revision of Prior Period, Reclassification, Adjustment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers		8	5
Transferred at point in time | Equipment sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 1,044	$ 1,007	$ 970