Business Segment Information (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2024		Dec. 31, 2023		Dec. 31, 2022
Segment Reporting Information [Line Items]
Total operating revenues		$ 3,770		$ 3,906		$ 4,169
Selling, general and administrative		1,330		1,368		1,408
Expenses related to strategic alternatives review		(35)		(8)
Segment Adjusted EBITDA		845		818		790
Depreciation, amortization and accretion		(665)		(656)		(700)
Loss on impairment of licenses	$ (136)	(136)		0		(3)
Gain (loss) on asset disposals, net		(18)		(17)		(19)
Gain (loss) on license sales and exchanges, net		(3)		2		0
Gain on sale of business and other exit costs, net		0		0		1
Equity in earnings of unconsolidated entities		161		158		158
Interest and dividend income		12		10		8
Interest expense		(183)		(196)		(163)
Income (loss) before income taxes		(22)		111		72
Loss on impairment of licenses	$ (136)	(136)		0		(3)
Investments in unconsolidated entities		454		461		452
Total assets		10,449	[1]	10,750	[1]	11,119
Capital expenditures		577		611		717
Intersegment revenues
Segment Reporting Information [Line Items]
Total operating revenues		131		127		123
Operating segments excluding intersegment elimination
Segment Reporting Information [Line Items]
Total operating revenues		3,901		4,033		4,292
Intersegment eliminations
Segment Reporting Information [Line Items]
Total operating revenues		(131)		(127)		(123)
Wireless | Operating segment
Segment Reporting Information [Line Items]
Total operating revenues		3,667		3,805		4,076
Selling, general and administrative		1,298		1,334		1,376
Expenses related to strategic alternatives review		(33)		(8)
Segment Adjusted EBITDA		719		697		677
Depreciation, amortization and accretion		(620)		(610)		(655)
Loss on impairment of licenses		(136)				(3)
Gain (loss) on asset disposals, net		(17)		(19)		(19)
Gain (loss) on license sales and exchanges, net		(3)		2
Gain on sale of business and other exit costs, net						1
Loss on impairment of licenses		(136)				(3)
Capital expenditures		554		580		689
Wireless | Intersegment revenues
Segment Reporting Information [Line Items]
Total operating revenues		0		0		0
Wireless | Operating segments excluding intersegment elimination
Segment Reporting Information [Line Items]
Total operating revenues		3,667		3,805		4,076
Towers | Operating segment
Segment Reporting Information [Line Items]
Total operating revenues		103		101		93
Selling, general and administrative		32		34		32
Expenses related to strategic alternatives review		(2)		0
Segment Adjusted EBITDA		126		121		113
Depreciation, amortization and accretion		(45)		(46)		(45)
Loss on impairment of licenses		0				0
Gain (loss) on asset disposals, net		(1)		2		0
Gain (loss) on license sales and exchanges, net		0		0
Gain on sale of business and other exit costs, net						0
Loss on impairment of licenses		0				0
Capital expenditures		23		31		28
Towers | Intersegment revenues
Segment Reporting Information [Line Items]
Total operating revenues		131		127		123
Towers | Operating segments excluding intersegment elimination
Segment Reporting Information [Line Items]
Total operating revenues		234		228		216
Service
Segment Reporting Information [Line Items]
Total operating revenues		2,987		3,044		3,125
Cost of goods and services sold		724		740		755
Service | Wireless | Operating segment
Segment Reporting Information [Line Items]
Cost of goods and services sold		777		794		807
Service | Towers | Operating segment
Segment Reporting Information [Line Items]
Cost of goods and services sold		78		73		71
Equipment sales
Segment Reporting Information [Line Items]
Total operating revenues		783		862		1,044
Cost of goods and services sold		906		988		1,216
Equipment sales | Wireless | Operating segment
Segment Reporting Information [Line Items]
Cost of goods and services sold		906		988		1,216
Equipment sales | Towers | Operating segment
Segment Reporting Information [Line Items]
Cost of goods and services sold		$ 0		$ 0		$ 0

[1] The consolidated total assets as of December 31, 2024 and 2023, include assets held by consolidated variable interest entities (VIEs) of $1,011 million and $1,217 million, respectively, which are not available to be used to settle the obligations of UScellular. The consolidated total liabilities as of December 31, 2024 and 2023, include certain liabilities of consolidated VIEs of $27 million and $26 million, respectively, for which the creditors of the VIEs have no recourse to the general credit of UScellular. See Note 15 — Variable Interest Entities for additional information.