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Employee Benefit Plans, other Post-Retirement Benefits (Details) (Post Retirement Medical Benefits, USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Amounts included in the Consolidated Balance Sheet, before tax      
Net prior service costs $ 17,246,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax $ 18,833,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax  
Net actuarial loss (8,436,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax (20,713,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax  
Sum net prior service cost and net actuarial loss 8,810,000us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax (1,880,000)us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax  
Amounts to be amortized to net benefit cost      
Estimated net actuarial loss amortized from accumulated other comprehensive loss into net periodic benefit cost next year 300,000us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss    
Estimated prior service cost gain amortized from accumulated other comprehensive loss into net periodic benefit cost next year 3,400,000us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit    
Change in benefit obligation      
Benefit obligation at beginning of year 46,142,000us-gaap_DefinedBenefitPlanBenefitObligation 54,568,000us-gaap_DefinedBenefitPlanBenefitObligation  
Service cost 1,018,000us-gaap_DefinedBenefitPlanServiceCost 1,348,000us-gaap_DefinedBenefitPlanServiceCost 1,197,000us-gaap_DefinedBenefitPlanServiceCost
Interest cost 2,255,000us-gaap_DefinedBenefitPlanInterestCost 2,137,000us-gaap_DefinedBenefitPlanInterestCost 2,297,000us-gaap_DefinedBenefitPlanInterestCost
Plan amendments (2,057,000)us-gaap_DefinedBenefitPlanPlanAmendments    
Actuarial (gain) loss (10,897,000)us-gaap_DefinedBenefitPlanActuarialGainLoss (9,437,000)us-gaap_DefinedBenefitPlanActuarialGainLoss  
Prescription drug subsidy 264,000us-gaap_DefinedBenefitPlanGrossPrescriptionDrugSubsidyReceiptsReceived    
Employee contribution 2,216,000us-gaap_DefinedBenefitPlanContributionsByPlanParticipants 2,230,000us-gaap_DefinedBenefitPlanContributionsByPlanParticipants  
Benefits paid (4,296,000)us-gaap_DefinedBenefitPlanBenefitsPaid (4,704,000)us-gaap_DefinedBenefitPlanBenefitsPaid  
Benefit obligation at end of year 34,645,000us-gaap_DefinedBenefitPlanBenefitObligation 46,142,000us-gaap_DefinedBenefitPlanBenefitObligation 54,568,000us-gaap_DefinedBenefitPlanBenefitObligation
Change in plan assets      
Fair value of plan assets at beginning of year 49,743,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets 45,047,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets  
Actual return (loss) on plan assets 3,495,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets 6,973,000us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets  
Employee contribution 2,216,000us-gaap_DefinedBenefitPlanContributionsByPlanParticipants 2,230,000us-gaap_DefinedBenefitPlanContributionsByPlanParticipants  
Employer contribution 166,000us-gaap_DefinedBenefitPlanContributionsByEmployer 197,000us-gaap_DefinedBenefitPlanContributionsByEmployer  
Benefits paid 4,296,000us-gaap_DefinedBenefitPlanBenefitsPaid 4,704,000us-gaap_DefinedBenefitPlanBenefitsPaid  
Fair value of plan assets at end of year 51,324,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets 49,743,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets 45,047,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Funded status 16,679,000us-gaap_DefinedBenefitPlanFundedStatusOfPlan 3,601,000us-gaap_DefinedBenefitPlanFundedStatusOfPlan  
Benefit plan, investment and asset allocation      
Three year return 13.26%tds_DefinedBenefitPlanThreeYearReturnOnAssets    
Five year return 10.30%tds_DefinedBenefitPlanFiveYearReturnOnAssets    
Net periodic benefit cost      
Service cost 1,018,000us-gaap_DefinedBenefitPlanServiceCost 1,348,000us-gaap_DefinedBenefitPlanServiceCost 1,197,000us-gaap_DefinedBenefitPlanServiceCost
Interest cost 2,255,000us-gaap_DefinedBenefitPlanInterestCost 2,137,000us-gaap_DefinedBenefitPlanInterestCost 2,297,000us-gaap_DefinedBenefitPlanInterestCost
Expected return on plan assets (3,402,000)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets (3,065,000)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets (2,995,000)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
Amortization of prior service costs (3,644,000)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit [1] (3,605,000)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit [1] (3,735,000)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit [1]
Amortization of actuarial losses 1,287,000us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses [2] 2,452,000us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses [2] 2,517,000us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses [2]
Net post-retirement cost (2,486,000)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost (733,000)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost (719,000)us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
Benefit obligations      
Discount rate 4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate  
Net periodic benefit cost assumptions      
Discount rate 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate 4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate  
Expected return on plan assets 7.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets 7.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets  
Discount rate assumptions The discount rate for 2014 and 2013 was determined using a hypothetical Aa spot yield curve represented by a series of annualized individual spot discount rates from six months to 99 years. The spot rate curve was derived from a direct calculation of the implied forward rate curve based on the included bond cash flows. This yield curve, when populated with projected cash flows that represent the expected timing and amount of TDS plan benefit payments, produces a single effective interest discount rate that is used to measure the plan’s liabilities. The expected rate of return was determined using the target asset allocation for the TDS plan and rate of return expectations for each asset class. The measurement date for actuarial determination was December 31, 2014. For measurement purposes, the annual rate of increase in the per capita cost of covered health care benefits was assumed for 2014 to be 7.8% for plan participants aged 65 and above, and 7.5% for participants under age 65. For all participants the 2014 annual rate of increase is expected to decrease to 5.0% by 2022. The 2013 expected rate of increase was 7.5% for plan participants aged 65 and above, and 7.9% for participants under age 65, decreasing to 5.0% for all participants by 2021. A 1% increase or decrease in assumed health care cost trend rates would have the following effects as of and for the year ended December 31, 2014:    
Health care trend rates      
Ultimate health care cost trend rate 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate  
One percent increase effect on total service and interest cost components 25,000us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents    
One percent decrease effect on total service and interest cost components (23,000)us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1    
One percent increase effect on post-retirement benefit obligation 423,000us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation    
One percent decrease effect on post-retirement benefit obligation (393,000)us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1    
Estimated future post-retirement benefit payments      
Estimated future post-retirement benefit payments - next twelve months 1,687,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths    
Estimated future post-retirement benefit payments - 2 years 1,719,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo    
Estimated future post-retirement benefit payments - 3 years 1,662,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree    
Estimated future post-retirement benefit payments - 4 years 1,652,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour    
Estimated future post-retirement benefit payments - 5 years 1,667,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive    
Estimated future post-retirement benefit payments - 6-10 years 9,442,000us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter    
65 and older
      
Health care trend rates      
Health care cost trend rate 7.80%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ tds_DefinedBenefitPlanParticipantsAxis
= tds_DefinedBenefitParticipantsMedicareEligibleMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 7.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ tds_DefinedBenefitPlanParticipantsAxis
= tds_DefinedBenefitParticipantsMedicareEligibleMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		  
Under 65
      
Health care trend rates      
Health care cost trend rate 7.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ tds_DefinedBenefitPlanParticipantsAxis
= tds_DefinedBenefitParticipantsNotMedicareEligibleMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 7.90%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ tds_DefinedBenefitPlanParticipantsAxis
= tds_DefinedBenefitParticipantsNotMedicareEligibleMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		  
Level 1
      
Change in plan assets      
Fair value of plan assets at end of year 51,323,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 49,732,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		  
Level 2
      
Change in plan assets      
Fair value of plan assets at end of year 1,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member		 11,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member		  
Bond Mutual Funds
      
Change in plan assets      
Fair value of plan assets at beginning of year 12,697,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 [3]    
Fair value of plan assets at end of year 12,842,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 [3]    
Benefit plan, investment and asset allocation      
Investment strategy of mutual fund The funds seek to achieve a maximum total return, consistent with preservation of capital and prudent investment management by investing in a wide spectrum of fixed income instruments including bonds, debt securities and other similar instruments issued by government and private-sector entities.    
Target asset allocation 30.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		    
Actual asset allocation 29.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 29.10%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		  
Bond Mutual Funds | Level 1
      
Change in plan assets      
Fair value of plan assets at end of year 12,842,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 [3] 12,697,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_DebtSecuritiesMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 [3]  
Equity Mutual Funds | U.S. Large Cap
      
Change in plan assets      
Fair value of plan assets at beginning of year 20,861,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesLargeCapMutualFundMember		 [4]    
Fair value of plan assets at end of year 20,191,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesLargeCapMutualFundMember		 [4]    
Benefit plan, investment and asset allocation      
Investment strategy of mutual fund The funds seek to track the performance of several benchmark indices that measure the investment return of large-capitalization stocks. The funds attempt to replicate the indices by investing substantially all of their assets in the stocks that make up the various indices in approximately the same proportion as the weighting in the indices.    
Equity Mutual Funds | U.S. Large Cap | Level 1
      
Change in plan assets      
Fair value of plan assets at end of year 20,191,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesLargeCapMutualFundMember		 [4] 20,861,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesLargeCapMutualFundMember		 [4]  
Equity Mutual Funds | U.S. Small Cap
      
Change in plan assets      
Fair value of plan assets at beginning of year 4,500,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesSmallCapMutualFundMember		 [5]    
Fair value of plan assets at end of year 4,234,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesSmallCapMutualFundMember		 [5]    
Benefit plan, investment and asset allocation      
Investment strategy of mutual fund The fund seeks to track the performance of a benchmark index that measures the investment return of small-capitalization stocks. The fund attempts to replicate the index by investing substantially all of its assets in the stocks that make up the index in approximately the same proportion as the weighting in the index.    
Equity Mutual Funds | U.S. Small Cap | Level 1
      
Change in plan assets      
Fair value of plan assets at end of year 4,234,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesSmallCapMutualFundMember		 [5] 4,500,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesSmallCapMutualFundMember		 [5]  
Equity Mutual Funds | International
      
Change in plan assets      
Fair value of plan assets at beginning of year 9,876,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		 [6]    
Fair value of plan assets at end of year 12,003,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		 [6]    
Benefit plan, investment and asset allocation      
Investment strategy of mutual fund The funds seek to provide long-term capital appreciation by investing in the stocks of companies located outside the United States that are considered to have the potential for above-average capital appreciation.    
Target asset allocation 24.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		    
Actual asset allocation 23.40%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		 19.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		  
Equity Mutual Funds | International | Level 1
      
Change in plan assets      
Fair value of plan assets at end of year 12,003,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		 [6] 9,876,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_InvestmentTypeAxis
= tds_InternationalMutualFundMember		 [6]  
Equity Mutual Funds | United States
      
Benefit plan, investment and asset allocation      
Target asset allocation 46.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesMutualFundsMember		    
Actual asset allocation 47.60%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesMutualFundsMember		 51.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_EquityFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_InvestmentTypeAxis
= tds_UnitedStatesMutualFundsMember		  
Money Market Mutual Funds
      
Change in plan assets      
Fair value of plan assets at beginning of year 1,798,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 [7]    
Fair value of plan assets at end of year 2,053,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 [7]    
Benefit plan, investment and asset allocation      
Investment strategy of mutual fund The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity by investing in a diversified portfolio of high-quality, dollar-denominated short-term debt securities.    
Money Market Mutual Funds | Level 1
      
Change in plan assets      
Fair value of plan assets at end of year 2,053,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 [7] 1,798,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 [7]  
Other
      
Change in plan assets      
Fair value of plan assets at end of year 1,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		 11,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember		  
Other | Level 2
      
Change in plan assets      
Fair value of plan assets at end of year $ 1,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member		 $ 11,000us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_OtherAggregatedInvestmentsMember
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_DefinedBenefitPostretirementHealthCoverageMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member		  
[1] Based on straight-line amortization over the average time remaining before active employees become fully eligible for plan benefits.
[2] Based on straight-line amortization over the average time remaining before active employees retire.
[3] Bond - The funds seek to achieve a maximum total return, consistent with preservation of capital and prudent investment management by investing in a wide spectrum of fixed income instruments including bonds, debt securities and other similar instruments issued by government and private-sector entities.
[4] US large cap - The funds seek to track the performance of several benchmark indices that measure the investment return of large-capitalization stocks. The funds attempt to replicate the indices by investing substantially all of their assets in the stocks that make up the various indices in approximately the same proportion as the weighting in the indices.
[5] US small cap - The fund seeks to track the performance of a benchmark index that measures the investment return of small-capitalization stocks. The fund attempts to replicate the index by investing substantially all of its assets in the stocks that make up the index in approximately the same proportion as the weighting in the index.
[6] International equity - The appreciation by investing in the stocks of companies located outside the United States that are considered to have the potential for above-average capital appreciation. funds seek to provide long-term capital.
[7] Money market - The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity by investing in a diversified portfolio of high-quality, dollar-denominated short-term debt securities.