<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2025"
  xmlns:lbrda="http://libertybroadband.com/20260819"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:us-gaap="http://fasb.org/us-gaap/2025"
  xmlns:xbrldi="http://xbrl.org/2006/xbrldi"
  xmlns:xlink="http://www.w3.org/1999/xlink">
    <link:schemaRef xlink:href="lbrda-20260819.xsd" xlink:type="simple"/>
    <context id="c20260819to20260819">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001611983</identifier>
        </entity>
        <period>
            <startDate>2026-08-19</startDate>
            <endDate>2026-08-19</endDate>
        </period>
    </context>
    <context id="c20260819to20260819_StatementClassOfStockAxis_CommonClassCMember">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001611983</identifier>
            <segment>
                <xbrldi:explicitMember dimension="us-gaap:StatementClassOfStockAxis">us-gaap:CommonClassCMember</xbrldi:explicitMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-08-19</startDate>
            <endDate>2026-08-19</endDate>
        </period>
    </context>
    <context id="c20260819to20260819_StatementClassOfStockAxis_CommonClassAMember">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001611983</identifier>
            <segment>
                <xbrldi:explicitMember dimension="us-gaap:StatementClassOfStockAxis">us-gaap:CommonClassAMember</xbrldi:explicitMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-08-19</startDate>
            <endDate>2026-08-19</endDate>
        </period>
    </context>
    <context id="c20260819to20260819_StatementClassOfStockAxis_SeriesACumulativeRedeemablePreferredStockMember">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001611983</identifier>
            <segment>
                <xbrldi:explicitMember dimension="us-gaap:StatementClassOfStockAxis">lbrda:SeriesACumulativeRedeemablePreferredStockMember</xbrldi:explicitMember>
            </segment>
        </entity>
        <period>
            <startDate>2026-08-19</startDate>
            <endDate>2026-08-19</endDate>
        </period>
    </context>
    <dei:AmendmentFlag
      contextRef="c20260819to20260819"
      id="Fact_c3ffd5b41dc04ccaae5076312566ac40">false</dei:AmendmentFlag>
    <dei:CurrentFiscalYearEndDate
      contextRef="c20260819to20260819"
      id="Fact_c9124b6e63cc4240ad7840ebeee1f82a">--12-31</dei:CurrentFiscalYearEndDate>
    <dei:EntityCentralIndexKey
      contextRef="c20260819to20260819"
      id="Fact_f240b5bfeadc4921b35fa859b54c43f0">0001611983</dei:EntityCentralIndexKey>
    <dei:SecurityExchangeName
      contextRef="c20260819to20260819_StatementClassOfStockAxis_SeriesACumulativeRedeemablePreferredStockMember"
      id="Fact_9ef5a5b0ee59460383c210d5c47deef8">NASDAQ</dei:SecurityExchangeName>
    <dei:SecurityExchangeName
      contextRef="c20260819to20260819_StatementClassOfStockAxis_CommonClassCMember"
      id="Fact_ee33c060a1f547b782c9967a81f57ac4">NASDAQ</dei:SecurityExchangeName>
    <dei:SecurityExchangeName
      contextRef="c20260819to20260819_StatementClassOfStockAxis_CommonClassAMember"
      id="Fact_a5c046fe5d1d4328b623c2767210457b">NASDAQ</dei:SecurityExchangeName>
    <dei:DocumentType
      contextRef="c20260819to20260819"
      id="Fact_056a5e8851b74a91a4189a367795f1ec">8-K</dei:DocumentType>
    <dei:DocumentPeriodEndDate
      contextRef="c20260819to20260819"
      id="Fact_263fd350ebc942f5b467441c5dba7879">2026-08-19</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName
      contextRef="c20260819to20260819"
      id="Fact_038197d6d02a41cb8948ef4c490a71d0">LIBERTY BROADBAND CORPORATION</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode
      contextRef="c20260819to20260819"
      id="Fact_71dd5f208aac4859a912b44bbd649235">DE</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber
      contextRef="c20260819to20260819"
      id="Fact_37f2edf1022b4acd849d943dc56ea944">001-36713</dei:EntityFileNumber>
    <dei:EntityTaxIdentificationNumber
      contextRef="c20260819to20260819"
      id="Fact_41ac962bc038407bafdef1053ad8c027">47-1211994</dei:EntityTaxIdentificationNumber>
    <dei:EntityAddressAddressLine1
      contextRef="c20260819to20260819"
      id="Fact_4057d52e083c407ca7508f08ef61b176">400 Washington Blvd.</dei:EntityAddressAddressLine1>
    <dei:EntityAddressCityOrTown
      contextRef="c20260819to20260819"
      id="Fact_5c2010a5c0614d90ad369e8f8c283157">Stamford</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince
      contextRef="c20260819to20260819"
      id="Fact_8b3f02134fd24fb08cb625afbe730729">CT</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode
      contextRef="c20260819to20260819"
      id="Fact_0b41d08e93fd431fa6a5fd1cacfcf27f">06902</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode
      contextRef="c20260819to20260819"
      id="Fact_66bea720f1e9488c8a420b10e15c987f">203</dei:CityAreaCode>
    <dei:LocalPhoneNumber
      contextRef="c20260819to20260819"
      id="Fact_5e507aa664c94cf58598eb30b974f0b4">905-7801</dei:LocalPhoneNumber>
    <dei:WrittenCommunications
      contextRef="c20260819to20260819"
      id="Fact_3970c8f5f3554f3487c88be8ff8ca74e">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial
      contextRef="c20260819to20260819"
      id="Fact_21414486a3a246118ae9db903822fac3">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer
      contextRef="c20260819to20260819"
      id="Fact_94e17ac05d7248f192e36c3716d3e168">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer
      contextRef="c20260819to20260819"
      id="Fact_82986d2e375b46a9ac3aabf33c496c23">false</dei:PreCommencementIssuerTenderOffer>
    <dei:Security12bTitle
      contextRef="c20260819to20260819_StatementClassOfStockAxis_CommonClassAMember"
      id="Fact_b9ee1695a5ba4d528d10e3d3a48c51d5">Series A common stock</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="c20260819to20260819_StatementClassOfStockAxis_CommonClassAMember"
      id="Fact_78874b3cdad04b55b953dfebb30404d4">LBRDA</dei:TradingSymbol>
    <dei:Security12bTitle
      contextRef="c20260819to20260819_StatementClassOfStockAxis_CommonClassCMember"
      id="Fact_34b61353ec8244e3a0505c10a816b726">Series C common stock</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="c20260819to20260819_StatementClassOfStockAxis_CommonClassCMember"
      id="Fact_a0599bd554104c5cb0fe3c444d230d8c">LBRDK</dei:TradingSymbol>
    <dei:Security12bTitle
      contextRef="c20260819to20260819_StatementClassOfStockAxis_SeriesACumulativeRedeemablePreferredStockMember"
      id="Fact_323d2afdbd3847cab81cb879cf565f31">Series A Cumulative Redeemable preferred stock</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="c20260819to20260819_StatementClassOfStockAxis_SeriesACumulativeRedeemablePreferredStockMember"
      id="Fact_671979cb079448d383fea6ad94607974">LBRDP</dei:TradingSymbol>
    <dei:EntityEmergingGrowthCompany
      contextRef="c20260819to20260819"
      id="Fact_cf7bf064760f4cc9aa83483d3c5717bb">false</dei:EntityEmergingGrowthCompany>
</xbrl>
