| Document and Entity Information Document | Nov. 30, 2020 |
| Entity Central Index Key | 0000821130 |
| Entity Emerging Growth Company | false |
| Pre-commencement Issuer Tender Offer | false |
| Pre-commencement Tender Offer | false |
| Soliciting Material | false |
| Written Communications | false |
| Document Type | 8-K |
| Document Period End Date | Nov. 30, 2020 |
| Entity Incorporation, State or Country Code | DE |
| Entity Registrant Name | UNITED STATES CELLULAR CORPORATION |
| Entity File Number | 001-09712 |
| Entity Tax Identification Number | 62-1147325 |
| Entity Address, Address Line One | 8410 West Bryn Mawr |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60631 |
| City Area Code | (773) |
| Local Phone Number | 399-8900 |
| Amendment Flag | false |
| Common Shares | |
| Title of 12(b) Security | Common Shares, $1 par value |
| Trading Symbol | USM |
| Security Exchange Name | NYSE |
| 6.95% Senior Notes | |
| Title of 12(b) Security | 6.95% Senior Notes due 2060 |
| Trading Symbol | UZA |
| Security Exchange Name | NYSE |
| 7.25% 2063 Senior Notes | |
| Title of 12(b) Security | 7.25% Senior Notes due 2063 |
| Trading Symbol | UZB |
| Security Exchange Name | NYSE |
| 7.25% 2064 Senior Notes | |
| Title of 12(b) Security | 7.25% Senior Notes due 2064 |
| Trading Symbol | UZC |
| Security Exchange Name | NYSE |
| Six Point Two Five Percent 2069 Senior Notes | |
| Title of 12(b) Security | 6.25% Senior Notes due 2069 |
| Trading Symbol | UZD |
| Security Exchange Name | NYSE |
