Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Series A Common and Common shares	Capital in excess of par value	Treasury shares	Accumulated other comprehensive income (loss)	Retained earnings	Total TDS shareholders' equity	Noncontrolling interests
Cumulative effect of accounting changes	$ 193				$ (1)	$ 163	$ 162	$ 31
Beginning balance at Dec. 31, 2017	4,892	$ 1	$ 2,413	$ (669)	(1)	2,525	4,269	623
Net income attributable to TDS shareholders	72					72	72
Net income attributable to noncontrolling interests classified as equity	16						0	16
Other comprehensive loss	(1)				(1)		(1)
TDS Common and Series A Common share dividends	(36)					(36)	(36)
Dividend reinvestment plan	6			13		(7)	6
Incentive and compensation plans	7			32		(25)	7
Adjust investment in subsidiaries for repurchases, issuances and other compensation plans	18		(1)				(1)	19
Stock-based compensation awards	6		6				6
Distributions to noncontrolling interests	(1)						0	(1)
Ending balance at Jun. 30, 2018	5,172	1	2,418	(624)	(3)	2,692	4,484	688
Cumulative effect of accounting changes	(1)					(1)	(1)
Beginning balance at Mar. 31, 2018	5,139	1	2,421	(643)	(3)	2,696	4,472	667
Net income attributable to TDS shareholders	33					33	33
Net income attributable to noncontrolling interests classified as equity	10						0	10
TDS Common and Series A Common share dividends	(18)					(18)	(18)
Dividend reinvestment plan	2			6		(4)	2
Incentive and compensation plans	(1)			13		(14)	(1)
Adjust investment in subsidiaries for repurchases, issuances and other compensation plans	6		(6)				(6)	12
Stock-based compensation awards	3		3				3
Distributions to noncontrolling interests	(1)						0	(1)
Ending balance at Jun. 30, 2018	5,172	1	2,418	(624)	(3)	2,692	4,484	688
Beginning balance at Dec. 31, 2018	5,293		2,432	(519)	(10)	2,656	4,560	733
Net income attributable to TDS shareholders	92					92	92
Net income attributable to noncontrolling interests classified as equity	17						0	17
TDS Common and Series A Common share dividends	(38)					(38)	(38)
Dividend reinvestment plan	9			11		(2)	9
Incentive and compensation plans	(6)			20		(26)	(6)
Adjust investment in subsidiaries for repurchases, issuances and other compensation plans	18		(2)				(2)	20
Stock-based compensation awards	8		8				8
Distributions to noncontrolling interests	(2)						0	(2)
Ending balance at Jun. 30, 2019	5,393	1	2,438	(488)	(10)	2,684	4,625	768
Cumulative effect of accounting changes	2					2	2
Beginning balance at Mar. 31, 2019	5,357	1	2,442	(505)	(10)	2,683	4,611	746
Net income attributable to TDS shareholders	33					33	33
Net income attributable to noncontrolling interests classified as equity	6						0	6
TDS Common and Series A Common share dividends	(19)					(19)	(19)
Dividend reinvestment plan	5			6		(1)	5
Incentive and compensation plans	(3)			11		(14)	(3)
Adjust investment in subsidiaries for repurchases, issuances and other compensation plans	9		(8)				(8)	17
Stock-based compensation awards	4		4				4
Distributions to noncontrolling interests	(1)						0	(1)
Ending balance at Jun. 30, 2019	$ 5,393	$ 1	$ 2,438	$ (488)	$ (10)	$ 2,684	$ 4,625	$ 768