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Basis of Presentation - Narrative (Details) - USD ($) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2022 | Sep. 30, 2021
Basis of Presentation [Line Items] |  |
Software license costs incurred but not yet paid | $ 135 | $ 15
TDS | UScellular |  |
Basis of Presentation [Line Items] |  |
Ownership percentage | 83.00% |

X
- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Used to group disclosures related to significant accounting policies. + References No definition available. + Details
Name: | usm_BasisOfPresentationLineItems
Namespace Prefix: | usm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Future cash outflow for software license agreements incurred but not yet paid. + References No definition available. + Details
Name: | usm_SoftwareLicenseCostsIncurredButNotYetPaid
Namespace Prefix: | usm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=usm_TelephoneandDataSystemsInc.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_OwnershipAxis=usm_UnitedStatesCellularCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |