Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Series A Common and Common shares	Additional paid-in capital	Treasury shares	Retained earnings	Total U.S. Cellular shareholders' equity	Noncontrolling interests
Beginning balance at Dec. 31, 2014	$ 3,313	$ 88	$ 1,473	$ (169)	$ 1,910	$ 3,302	$ 11
Net income attributable to U.S. Cellular shareholders	243				243	243
Net loss attributable to noncontrolling interests classified as equity	2						2
Repurchase of Common shares	(5)			(5)		(5)
Incentive and compensation plans	(2)			14	(16)	(2)
Stock-based compensation awards	17		17			17
Distributions to noncontrolling interests	(1)						(1)
Acquisition of assets in common control transaction	(1)		1		(2)	(1)
Ending balance at Sep. 30, 2015	3,566	88	1,491	(160)	2,135	3,554	12
Beginning balance at Dec. 31, 2015	3,571	88	1,497	(157)	2,133	3,561	10
Net income attributable to U.S. Cellular shareholders	53				53	53
Net loss attributable to noncontrolling interests classified as equity	1						1
Repurchase of Common shares	(2)			(2)		(2)
Incentive and compensation plans	4			23	(19)	4
Stock-based compensation awards	19		19			19
Distributions to noncontrolling interests	(1)						(1)
Ending balance at Sep. 30, 2016	$ 3,645	$ 88	$ 1,516	$ (136)	$ 2,167	$ 3,635	$ 10