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Long-Term Debt and Credit Facilities (Details 2) (USD $)
12 Months Ended 0 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Sep. 29, 2014
May 23, 2013
Oct. 02, 2014
Nov. 27, 2013
Apr. 02, 2013
Mar. 21, 2013
Dec. 27, 2013
Dec. 03, 2014
Apr. 02, 2014
Jun. 17, 2013
Jul. 15, 2013
Aug. 15, 2013
Feb. 15, 2015
Feb. 20, 2015
Apr. 30, 2011
Oct. 01, 2014
Apr. 01, 2014
Jan. 31, 2015
Long-term Debt and Credit Facilities                                          
Repayments of notes $ 800,000,000us-gaap_RepaymentsOfDebt $ 2,010,000,000us-gaap_RepaymentsOfDebt $ 5,118,000,000us-gaap_RepaymentsOfDebt                                    
Net loss (gain) on early retirement of debt 0us-gaap_GainsLossesOnExtinguishmentOfDebt (10,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt 179,000,000us-gaap_GainsLossesOnExtinguishmentOfDebt                                    
Interest expense:                                          
Interest Costs Incurred 1,358,000,000us-gaap_InterestCostsIncurred 1,339,000,000us-gaap_InterestCostsIncurred 1,362,000,000us-gaap_InterestCostsIncurred                                    
Capitalized interest (47,000,000)us-gaap_InterestCostsCapitalized (41,000,000)us-gaap_InterestCostsCapitalized (43,000,000)us-gaap_InterestCostsCapitalized                                    
Total interest expense 1,311,000,000us-gaap_InterestExpense 1,298,000,000us-gaap_InterestExpense 1,319,000,000us-gaap_InterestExpense                                    
Qwest Corporation | Revolving credit facility                                          
Interest expense:                                          
Debt to EBITDA ratio to be maintained under the Credit Facility 2.85ctl_DebtInstrumentCovenantDebtToEBITDARatio
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
                                       
CenturyLink, Inc. | Revolving credit facility                                          
Interest expense:                                          
Debt to EBITDA ratio to be maintained under the Credit Facility 4.0ctl_DebtInstrumentCovenantDebtToEBITDARatio
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
                                       
CenturyLink, Inc. | Letter of credit                                          
Long-term Debt and Credit Facilities                                          
Maximum borrowing capacity                                   160,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_LetterOfCreditMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Letters of credit outstanding 124,000,000us-gaap_LettersOfCreditOutstandingAmount
/ us-gaap_CreditFacilityAxis
= us-gaap_LetterOfCreditMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
132,000,000us-gaap_LettersOfCreditOutstandingAmount
/ us-gaap_CreditFacilityAxis
= us-gaap_LetterOfCreditMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
                                     
CenturyLink, Inc. | Credit Facility | Letter of credit                                          
Long-term Debt and Credit Facilities                                          
Maximum borrowing capacity                     400,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_LetterOfCreditMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
                   
Senior notes | Qwest Corporation | Minimum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 6.125%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
                                       
Senior notes | Qwest Corporation | Maximum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 8.375%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
                                       
Senior notes | Qwest Corporation | 6.875% Notes due 2054                                          
Long-term Debt and Credit Facilities                                          
Aggregate principal amount of debt issuance       500,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.875percentdue2054Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                                 
Interest rate, stated percentage (as a percent)       6.875%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.875percentdue2054Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                                 
Net proceeds from issuance of debt       483,000,000us-gaap_ProceedsFromDebtNetOfIssuanceCosts
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.875percentdue2054Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                                 
Senior notes | Qwest Corporation | 6.125% Notes due 2053                                          
Long-term Debt and Credit Facilities                                          
Aggregate principal amount of debt issuance         775,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.125PercentDue2053Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                               
Interest rate, stated percentage (as a percent)         6.125%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.125PercentDue2053Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                               
Net proceeds from issuance of debt         752,000,000us-gaap_ProceedsFromDebtNetOfIssuanceCosts
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.125PercentDue2053Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                               
Principal amount of debt that was sold pursuant to an over allotment option granted to the underwriters         25,000,000ctl_DebtInstrumentFaceAmountOfDebtSoldPursuantToOverAllotmentOptionGrantedToUnderwriters
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.125PercentDue2053Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                               
Senior notes | Qwest Corporation | Notes, 7.500 percent due 2014                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent)                                     7.50%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.500percentdue2014Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
   
Repayments of notes           600,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.500percentdue2014Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                             
Senior notes | CenturyLink, Inc. | Minimum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 5.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
                                       
Senior notes | CenturyLink, Inc. | Maximum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 7.65%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
                                       
Senior notes | CenturyLink, Inc. | 6.750% Notes due 2023                                          
Long-term Debt and Credit Facilities                                          
Aggregate principal amount of debt issuance             750,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.750PercentDue2023Member
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                           
Interest rate, stated percentage (as a percent)             6.75%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.750PercentDue2023Member
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                           
Net proceeds from issuance of debt             742,000,000us-gaap_ProceedsFromDebtNetOfIssuanceCosts
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.750PercentDue2023Member
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                           
Senior notes | CenturyLink, Inc. | 5.50% Notes                                          
Long-term Debt and Credit Facilities                                          
Repayments of notes               176,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes5.50PercentMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                         
Senior notes | CenturyLink, Inc. | 5.625% Notes due 2020                                          
Long-term Debt and Credit Facilities                                          
Aggregate principal amount of debt issuance                 1,000,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes5.625PercentDue2020Member
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                       
Interest rate, stated percentage (as a percent)                 5.625%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes5.625PercentDue2020Member
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                       
Net proceeds from issuance of debt                 988,000,000us-gaap_ProceedsFromDebtNetOfIssuanceCosts
/ us-gaap_DebtInstrumentAxis
= ctl_Notes5.625PercentDue2020Member
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                       
Senior notes | QCII | 7.125% Notes due 2018                                          
Long-term Debt and Credit Facilities                                          
Aggregate principal amount of debt issuance             800,000,000us-gaap_DebtInstrumentFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                           
Interest rate, stated percentage (as a percent)             7.125%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
    7.125%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                     
Repayments of long-term debt, including extinguishment fees and accrued interest             646,000,000ctl_RepaymentofLongTermDebtIncludingExtinguishmentFeesandAccruedInterest
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
    196,000,000ctl_RepaymentofLongTermDebtIncludingExtinguishmentFeesandAccruedInterest
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                     
Debt Instrument, Repurchased Face Amount             614,000,000us-gaap_DebtInstrumentRepurchasedFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
    186,000,000us-gaap_DebtInstrumentRepurchasedFaceAmount
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                     
Net loss (gain) on early retirement of debt             (7,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
    (3,000,000)us-gaap_GainsLossesOnExtinguishmentOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                     
Percentage of principal amount of notes for which tender offer was received and accepted (percent)             77.00%ctl_PercentageOfPrincipalAmountOfNotesForWhichTenderOfferIsAccepted
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.125PercentDue2018Member
/ dei_LegalEntityAxis
= ctl_QwestCommunicationsInternationalIncMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
                           
Senior notes | Embarq Corporation | Minimum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 7.082%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
                                       
Senior notes | Embarq Corporation | Maximum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 7.995%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
                                       
Interest expense:                                          
Percentage of net tangible assets allowed to secure senior notes (percent) 15.00%ctl_PercentageOfNetTangibleAssetsAllowedToSecureNotes
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
                                       
Line of credit | CenturyLink, Inc. | Credit Facility | Revolving credit facility                                          
Long-term Debt and Credit Facilities                                          
Revolving Credit Facility, Subsidiary Guarantors, Number                     9ctl_RevolvingCreditFacilitySubsidiaryGuarantorsNumber
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
                   
Maximum borrowing capacity                     2,000,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
                   
Number of lenders of Credit Facility                     16ctl_LendersofCreditFacilityNumber
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
                   
Line of credit | CenturyLink, Inc. | Credit Facility | Minimum | Revolving credit facility                                          
Long-term Debt and Credit Facilities                                          
Lender commitment                     3,500,000ctl_LineOfCreditFacilityLendingCommitmentPerLender
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
                   
Line of credit | CenturyLink, Inc. | Credit Facility | Minimum | Revolving credit facility | Base Rate                                          
Long-term Debt and Credit Facilities                                          
Interest rate margin (as a percent)                     0.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_VariableRateAxis
= us-gaap_BaseRateMember
                   
Line of credit | CenturyLink, Inc. | Credit Facility | Minimum | Revolving credit facility | London Interbank Offered Rate (LIBOR)                                          
Long-term Debt and Credit Facilities                                          
Interest rate margin (as a percent)                     1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember
                   
Line of credit | CenturyLink, Inc. | Credit Facility | Maximum | Revolving credit facility                                          
Long-term Debt and Credit Facilities                                          
Lender commitment                     198,500,000ctl_LineOfCreditFacilityLendingCommitmentPerLender
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
                   
Line of credit | CenturyLink, Inc. | Credit Facility | Maximum | Revolving credit facility | Base Rate                                          
Long-term Debt and Credit Facilities                                          
Interest rate margin (as a percent)                     1.25%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_VariableRateAxis
= us-gaap_BaseRateMember
                   
Line of credit | CenturyLink, Inc. | Credit Facility | Maximum | Revolving credit facility | London Interbank Offered Rate (LIBOR)                                          
Long-term Debt and Credit Facilities                                          
Interest rate margin (as a percent)                     2.25%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
/ us-gaap_CreditFacilityAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_DebtInstrumentAxis
= ctl_CreditFacilityMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_LineOfCreditMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_VariableRateAxis
= us-gaap_LondonInterbankOfferedRateLIBORMember
                   
First mortgage bonds | Embarq Corporation                                          
Interest expense:                                          
Percentage of subsidiary property, plant and equipment securing debt, (percent) 10.00%ctl_SubsidiaryPropertyPlantandEquipmentSecuringDebtPercent
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_MortgagesMember
                                       
First mortgage bonds | Embarq Corporation | Minimum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 7.125%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_MortgagesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
                                       
First mortgage bonds | Embarq Corporation | Maximum                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 8.77%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_MortgagesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
                                       
First mortgage bonds | Embarq Corporation | Notes, 7.460 Percent Due 2014                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent)                                       7.46%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.460PercentDue2014Member
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_MortgagesMember
 
Repayments of notes                       30,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes7.460PercentDue2014Member
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_MortgagesMember
                 
Other | Qwest Corporation | Floating interest rate notes                                          
Long-term Debt and Credit Facilities                                          
Repayments of notes                         750,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_NotesBearingFloatingInterestRateDue2013Member
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
               
Other | CenturyLink, Inc. | 5.50% Notes                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent)               5.50%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes5.50PercentMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
                         
Other | Embarq Corporation                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent) 9.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
                                       
Other | Embarq Corporation | 6.875% Notes                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent)                           6.875%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.875PercentMember
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
             
Repayments of notes                           59,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.875PercentMember
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
             
Other | Embarq Corporation | Notes 6.75 Percent                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent)                             6.75%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.75PercentMember
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
           
Repayments of notes                             50,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_Notes6.75PercentMember
/ dei_LegalEntityAxis
= ctl_EmbarqMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_NotesPayableOtherPayablesMember
           
Subsequent Event | CenturyLink, Inc. | Line of credit                                          
Long-term Debt and Credit Facilities                                          
Maximum borrowing capacity                                         100,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
/ us-gaap_CreditFacilityAxis
= us-gaap_LineOfCreditMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
Number of lenders of revolving line of credit                                         1ctl_LendersofRevolvingLineofCreditNumber
/ us-gaap_CreditFacilityAxis
= us-gaap_LineOfCreditMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
Subsequent Event | Senior notes | CenturyLink, Inc. | Series M 5.00% Notes                                          
Long-term Debt and Credit Facilities                                          
Interest rate, stated percentage (as a percent)                               5.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= ctl_SeriesM5.00NotesMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
         
Repayments of notes                               350,000,000us-gaap_RepaymentsOfDebt
/ us-gaap_DebtInstrumentAxis
= ctl_SeriesM5.00NotesMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_SeniorNotesMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
         
Subsequent Event | Term loan | Qwest Corporation                                          
Long-term Debt and Credit Facilities                                          
Aggregate principal amount of debt issuance                                 100,000,000us-gaap_DebtInstrumentFaceAmount
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= ctl_TermLoanMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
       
Interest expense:                                          
Proceeds from Issuance of Debt                                 $ 100,000,000us-gaap_ProceedsFromIssuanceOfDebt
/ dei_LegalEntityAxis
= ctl_QwestCorporationMember
/ us-gaap_LongtermDebtTypeAxis
= ctl_TermLoanMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember