Basis of Presentation - Narrative (Details)	3 Months Ended
Mar. 31, 2021
Basis of Presentation [Line Items]
Change in reportable segments	Change in Reportable SegmentsDuring the first quarter of 2021, TDS modified its reporting segment structure to combine its Wireline and Cable segments into a single reportable segment for TDS Telecom. TDS Telecom believes this presentation better articulates its progress and performance against its strategy, which includes a focus on overall broadband growth and future fiber deployment across its markets. This change also reflects TDS Telecom's progress in aligning its organizational, operational and support structures to leverage one cost base to better support its customers across all of its markets. Prior periods have been updated to conform to this revised presentation. See Note 13 — Business Segment Information for additional information on TDS' reportable segments.
UScellular
Basis of Presentation [Line Items]
TDS ownership of UScellular	82.00%

Disclosure about a restatement of previous periods' segment information resulting from a change in the composition of the entity's reportable segments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8981-108599

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