<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>100</ContextCount>
  <ElementCount>210</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>51</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>8</UnitCount>
  <MyReports>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSUNAUDITED</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - CONSOLIDATED BALANCE SHEETS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CONSOLIDATEDBALANCESHEETSUNAUDITED</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CONSOLIDATEDBALANCESHEETSUNAUDITEDParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSUNAUDITED</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSUNAUDITEDParenthetical</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Statement - CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUNAUDITED</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Disclosure - Background</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/Background</Role>
      <ShortName>Background</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Disclosure - Divestiture</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/Divestiture</Role>
      <ShortName>Divestiture</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - Goodwill and Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/GoodwillandIntangibleAssets</Role>
      <ShortName>Goodwill and Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - Revenue Recognition</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognition</Role>
      <ShortName>Revenue Recognition</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - Long-Term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LongTermDebt</Role>
      <ShortName>Long-Term Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - Fair Value of Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/FairValueofFinancialInstruments</Role>
      <ShortName>Fair Value of Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - Affiliate Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/AffiliateTransactions</Role>
      <ShortName>Affiliate Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - Commitments, Contingencies and Other Items</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CommitmentsContingenciesandOtherItems</Role>
      <ShortName>Commitments, Contingencies and Other Items</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - Other Financial Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/OtherFinancialInformation</Role>
      <ShortName>Other Financial Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - Labor Union Contracts</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LaborUnionContracts</Role>
      <ShortName>Labor Union Contracts</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Background (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/BackgroundPolicies</Role>
      <ShortName>Background (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Divestiture (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/DivestitureTables</Role>
      <ShortName>Divestiture (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/Divestiture</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Goodwill and Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/GoodwillandIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/GoodwillandIntangibleAssets</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Revenue Recognition (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionTables</Role>
      <ShortName>Revenue Recognition (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/RevenueRecognition</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Long-Term Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LongTermDebtTables</Role>
      <ShortName>Long-Term Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/LongTermDebt</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Fair Value of Financial Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/FairValueofFinancialInstrumentsTables</Role>
      <ShortName>Fair Value of Financial Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/FairValueofFinancialInstruments</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Affiliate Transactions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/AffiliateTransactionsTables</Role>
      <ShortName>Affiliate Transactions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/AffiliateTransactions</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Other Financial Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/OtherFinancialInformationTables</Role>
      <ShortName>Other Financial Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.lumen.com/role/OtherFinancialInformation</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Background - General (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/BackgroundGeneralDetails</Role>
      <ShortName>Background - General (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Background - Segments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/BackgroundSegmentsDetails</Role>
      <ShortName>Background - Segments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Divestiture - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/DivestitureAdditionalInformationDetails</Role>
      <ShortName>Divestiture - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Divestiture - Balance Sheet at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/DivestitureBalanceSheetatFairValueDetails</Role>
      <ShortName>Divestiture - Balance Sheet at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Goodwill and Intangible Assets - Goodwill Rollforward (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/GoodwillandIntangibleAssetsGoodwillRollforwardDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Goodwill Rollforward (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Goodwill and Intangible Assets - Intangible Assets, Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/GoodwillandIntangibleAssetsIntangibleAssetsNetDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Intangible Assets, Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - Goodwill and Intangible Assets - Amortization Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/GoodwillandIntangibleAssetsAmortizationExpenseDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Amortization Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Revenue Recognition - Disaggregation of Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionDisaggregationofRevenueDetails</Role>
      <ShortName>Revenue Recognition - Disaggregation of Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Revenue Recognition - Operating Lease Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionOperatingLeaseRevenueDetails</Role>
      <ShortName>Revenue Recognition - Operating Lease Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Revenue Recognition - Customer Receivables and Contract Balances (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionCustomerReceivablesandContractBalancesDetails</Role>
      <ShortName>Revenue Recognition - Customer Receivables and Contract Balances (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Revenue Recognition - Contract Liabilities, Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionContractLiabilitiesAdditionalInformationDetails</Role>
      <ShortName>Revenue Recognition - Contract Liabilities, Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Revenue Recognition - Performance Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionPerformanceObligationsDetails</Role>
      <ShortName>Revenue Recognition - Performance Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Revenue Recognition - Contract Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/RevenueRecognitionContractCostsDetails</Role>
      <ShortName>Revenue Recognition - Contract Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Long-Term Debt - Schedule of Long Term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LongTermDebtScheduleofLongTermDebtDetails</Role>
      <ShortName>Long-Term Debt - Schedule of Long Term Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Long-Term Debt - Schedule of Debt Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LongTermDebtScheduleofDebtMaturityDetails</Role>
      <ShortName>Long-Term Debt - Schedule of Debt Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Long-Term Debt - Subsequent Event (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LongTermDebtSubsequentEventDetails</Role>
      <ShortName>Long-Term Debt - Subsequent Event (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Fair Value of Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/FairValueofFinancialInstrumentsDetails</Role>
      <ShortName>Fair Value of Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.lumen.com/role/FairValueofFinancialInstrumentsTables</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Affiliate Transactions - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/AffiliateTransactionsAdditionalInformationDetails</Role>
      <ShortName>Affiliate Transactions - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Affiliate Transactions - Affiliate Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/AffiliateTransactionsAffiliateRevenueDetails</Role>
      <ShortName>Affiliate Transactions - Affiliate Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Commitments, Contingencies and Other Items (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/CommitmentsContingenciesandOtherItemsDetails</Role>
      <ShortName>Commitments, Contingencies and Other Items (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.lumen.com/role/CommitmentsContingenciesandOtherItems</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Other Financial Information - Other Current Assets, Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/OtherFinancialInformationOtherCurrentAssetsNetDetails</Role>
      <ShortName>Other Financial Information - Other Current Assets, Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Other Financial Information - Current Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/OtherFinancialInformationCurrentLiabilitiesDetails</Role>
      <ShortName>Other Financial Information - Current Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Other Financial Information - Other Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/OtherFinancialInformationOtherLiabilitiesDetails</Role>
      <ShortName>Other Financial Information - Other Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="lumn-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Labor Union Contracts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.lumen.com/role/LaborUnionContractsDetails</Role>
      <ShortName>Labor Union Contracts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.lumen.com/role/LaborUnionContracts</ParentRole>
      <Position>50</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-Q" isDefinitelyFs="true" isUsgaap="true" original="lumn-20260331.htm">lumn-20260331.htm</File>
    <File>lumn-20260331.xsd</File>
    <File>lumn-20260331_cal.xml</File>
    <File>lumn-20260331_def.xml</File>
    <File>lumn-20260331_lab.xml</File>
    <File>lumn-20260331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="383">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="32">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
