Name:	us-gaap_AssetsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Variable Interest Entities VIEs (Details) (USD $)	3 Months Ended	12 Months Ended
Variable Interest Entities VIEs (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Assets
Cash and cash equivalents	$ 336,893,000	$ 211,513,000	$ 398,541,000	$ 342,065,000
Other current assets	18,112,000us-gaap_OtherAssetsCurrent	90,834,000us-gaap_OtherAssetsCurrent
Licenses	1,827,102,000	1,443,438,000
Property, plant and equipment, net	2,645,117,000us-gaap_PropertyPlantAndEquipmentNet	2,728,217,000us-gaap_PropertyPlantAndEquipmentNet
Other assets and deferred charges	211,453,000us-gaap_OtherAssetsNoncurrent	276,218,000us-gaap_OtherAssetsNoncurrent
Liabilities
Current liabilities	861,834,000us-gaap_LiabilitiesCurrent	856,894,000us-gaap_LiabilitiesCurrent
Variable Interest Entities, Other Disclosures
Total winning bid	338,300,000usm_FccLicenseAuctionTotalWinningBid
Variable Interest Entities (VIE's)
Assets
Cash and cash equivalents	11,670,000	2,588,000
Other current assets	234,000	278,000
Licenses	651,281,000	312,977,000
Property, plant and equipment, net	10,129,000	10,671,000
Other assets and deferred charges	247,000	60,059,000
Total assets	673,561,000	386,573,000
Liabilities
Current liabilities	3,634,000	110,000
Deferred liabilities and credits	599,000	622,000
Total liabilities	4,233,000	732,000
Variable Interest Entities, Other Disclosures
Capital contributions, loans or advances	280,600,000
Advantage Spectrum L.P.
Variable Interest Entities, Other Disclosures
Federal Communications Commission deposit		60,000,000
Total winning bid	338,300,000
Other auction charges	2,300,000
Designated entity auction discount	25.00%
Licenses won	124
King Street Wireless L.P.
Variable Interest Entities, Other Disclosures
Cash distributions paid	60,000,000
King Street Wireless, L.P. distribution paid to U.S. Cellular	54,000,000
King Street Wireless, Inc.
Variable Interest Entities, Other Disclosures
King Street Wireless, L.P. distribution paid to King Street Wireless, Inc.	$ 6,000,000