Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total operating revenues	$ 1,261		$ 1,257
Selling, general and administrative	411		397
Depreciation, amortization and accretion	235		227
(Gain) loss on asset disposals, net	4		(5)
(Gain) loss on sale of business and other exit costs, net	0		(2)
(Gain) loss on license sales and exchanges, net	0		(2)
Operating income	72		94
Equity in earnings of unconsolidated entities	45		44
Interest and dividend income	6		9
Interest expense	(37)		(43)
Other, net	0
Income before income taxes	86		104
Income tax expense (benefit)	3		34
Net income	83		70
Depreciation, amortization and accretion	235		227
(Gain) loss on asset disposals, net	4		(5)
(Gain) loss on sale of business and other exit costs, net	0		(2)
(Gain) loss on license sales and exchanges, net	0		(2)
Interest expense	37		43
Income tax expense	3		34
Adjusted EBITDA	362		365
Investments in unconsolidated entities	509		507	$ 488
Total assets	10,895	[1]	10,787	$ 10,781	[1]
Capital expenditures	292		147
Service
Segment Reporting Information [Line Items]
Total operating revenues	1,026		995
Cost of goods and services	293		284
Equipment and product sales
Segment Reporting Information [Line Items]
Total operating revenues	235		262
Cost of goods and services	246		264
U.S. Cellular
Segment Reporting Information [Line Items]
Total operating revenues	963		966
Selling, general and administrative	335		326
Depreciation, amortization and accretion	177		169
(Gain) loss on asset disposals, net	4		2
(Gain) loss on sale of business and other exit costs, net			(2)
(Gain) loss on license sales and exchanges, net			(2)
Operating income	50		64
Equity in earnings of unconsolidated entities	45		44
Interest and dividend income	4		6
Interest expense	(24)		(29)
Other, net	1
Income before income taxes	76		85
Income tax expense (benefit)	4		27
Net income	72		58
Depreciation, amortization and accretion	177		169
(Gain) loss on asset disposals, net	4		2
(Gain) loss on sale of business and other exit costs, net			(2)
(Gain) loss on license sales and exchanges, net			(2)
Interest expense	24		29
Income tax expense	4		27
Adjusted EBITDA	281		281
Investments in unconsolidated entities	469		468
Total assets	8,251		8,229
Capital expenditures	236		102
U.S. Cellular | Service
Segment Reporting Information [Line Items]
Total operating revenues	762		741
Cost of goods and services	180		176
U.S. Cellular | Equipment and product sales
Segment Reporting Information [Line Items]
Total operating revenues	201		225
Cost of goods and services	217		233
TDS Telecom Total
Segment Reporting Information [Line Items]
Total operating revenues	240		230
Selling, general and administrative	65		61
Depreciation, amortization and accretion	52		50
(Gain) loss on asset disposals, net	0		(7)
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Operating income	28		37
Equity in earnings of unconsolidated entities	0		0
Interest and dividend income	2		3
Interest expense	1		0
Other, net	0
Income before income taxes	31		40
Income tax expense (benefit)	4		10
Net income	28		31
Depreciation, amortization and accretion	52		50
(Gain) loss on asset disposals, net	0		(7)
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Interest expense	(1)		0
Income tax expense	4		10
Adjusted EBITDA	82		83
Investments in unconsolidated entities	4		4
Total assets	2,221		1,986
Capital expenditures	54		42
TDS Telecom Total | Service
Segment Reporting Information [Line Items]
Total operating revenues	240		230
Cost of goods and services	95		88
TDS Telecom Total | Equipment and product sales
Segment Reporting Information [Line Items]
Total operating revenues	0		0
Cost of goods and services	0		0
TDS Telecom Wireline
Segment Reporting Information [Line Items]
Total operating revenues	169		171
Selling, general and administrative	48		47
Depreciation, amortization and accretion	32		34
(Gain) loss on asset disposals, net	0		(7)
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Operating income	23		34
Equity in earnings of unconsolidated entities	0		0
Interest and dividend income	2		3
Interest expense	1		1
Other, net	0
Income before income taxes	26		38
Depreciation, amortization and accretion	32		34
(Gain) loss on asset disposals, net	0		(7)
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Interest expense	(1)		(1)
Adjusted EBITDA	57		63
Investments in unconsolidated entities	4		4
Total assets	1,497		1,353
Capital expenditures	39		29
TDS Telecom Wireline | Service
Segment Reporting Information [Line Items]
Total operating revenues	169		170
Cost of goods and services	65		63
TDS Telecom Wireline | Equipment and product sales
Segment Reporting Information [Line Items]
Total operating revenues	0		0
Cost of goods and services	0		0
TDS Telecom Cable
Segment Reporting Information [Line Items]
Total operating revenues	71		60
Selling, general and administrative	17		14
Depreciation, amortization and accretion	19		17
(Gain) loss on asset disposals, net	0		0
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Operating income	5		2
Equity in earnings of unconsolidated entities	0		0
Interest and dividend income	0		0
Interest expense	0		0
Other, net	0
Income before income taxes	5		3
Depreciation, amortization and accretion	19		17
(Gain) loss on asset disposals, net	0		0
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Interest expense	0		0
Adjusted EBITDA	25		20
Investments in unconsolidated entities	0		0
Total assets	733		641
Capital expenditures	15		13
TDS Telecom Cable | Service
Segment Reporting Information [Line Items]
Total operating revenues	71		60
Cost of goods and services	30		26
TDS Telecom Cable | Equipment and product sales
Segment Reporting Information [Line Items]
Total operating revenues	0		0
Cost of goods and services	0		0
Corporate, Eliminations and Other
Segment Reporting Information [Line Items]
Total operating revenues	58		61
Selling, general and administrative	11		10
Depreciation, amortization and accretion	6		8
(Gain) loss on asset disposals, net	0		0
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Operating income	(6)		(7)
Equity in earnings of unconsolidated entities	0		0
Interest and dividend income	0		0
Interest expense	(14)		(14)
Other, net	(1)
Income before income taxes	(21)		(21)
Income tax expense (benefit)	(5)		(3)
Net income	(17)		(19)
Depreciation, amortization and accretion	6		8
(Gain) loss on asset disposals, net	0		0
(Gain) loss on sale of business and other exit costs, net			0
(Gain) loss on license sales and exchanges, net			0
Interest expense	14		14
Income tax expense	(5)		(3)
Adjusted EBITDA	(1)		1
Investments in unconsolidated entities	36		35
Total assets	423		572
Capital expenditures	2		3
Corporate, Eliminations and Other | Service
Segment Reporting Information [Line Items]
Total operating revenues	24		24
Cost of goods and services	18		20
Corporate, Eliminations and Other | Equipment and product sales
Segment Reporting Information [Line Items]
Total operating revenues	34		37
Cost of goods and services	$ 29		$ 31

[1] The consolidated total assets as of March 31, 2020 and December 31, 2019, include assets held by consolidated variable interest entities (VIEs) of $917 million and $915 million, respectively, which are not available to be used to settle the obligations of TDS. The consolidated total liabilities as of March 31, 2020 and December 31, 2019, include certain liabilities of consolidated VIEs of $18 million and $20 million, respectively, for which the creditors of the VIEs have no recourse to the general credit of TDS. See Note 10 — Variable Interest Entities for additional information.