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        <period>
            <startDate>2026-07-29</startDate>
            <endDate>2026-07-29</endDate>
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    <context id="offrl_1">
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    <context id="offrl_2">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001166691</identifier>
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        <period>
            <startDate>2026-07-29</startDate>
            <endDate>2026-07-29</endDate>
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    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
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    <ffd:FormTp contextRef="rc" id="ixv-375">S-4</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-376">S-4</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-377">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-378">0001166691</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-379">COMCAST CORP</dei:EntityRegistrantName>
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      contextRef="offrl_1"
      decimals="0"
      id="ixv-422"
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-423"
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      contextRef="offrl_1"
      decimals="7"
      id="ixv-424"
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      decimals="7"
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      id="ixv-431"
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    <ffd:Rule457fFlg contextRef="offrl_1" id="ixv-437">true</ffd:Rule457fFlg>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-438">(1) Represents the aggregate principal amount of the notes to be offered in the exchange offer to which the registration statement relates. (2) Calculated in accordance with Rule 457(f) of the Securities Act of 1933, as amended.</ffd:OfferingNote>
    <ffd:AmtSctiesRcvd
      contextRef="offrl_1"
      decimals="0"
      id="ixv-439"
      unitRef="Shares">1172013000</ffd:AmtSctiesRcvd>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-440"
      unitRef="USD">1.00</ffd:ValSctiesRcvdPerShr>
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      contextRef="offrl_1"
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      id="ixv-441"
      unitRef="USD">1172013000.00</ffd:ValSctiesRcvd>
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      contextRef="offrl_1"
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      id="ixv-442"
      unitRef="USD">1172013000.00</ffd:FeeNoteMaxAggtOfferingPric>
    <ffd:OfferingNote contextRef="offrl_2" id="ixv-443">(3) No separate consideration will be received for the guarantees. Each of NBCUniversal Media, LLC and Comcast Cable Communications, LLC will guarantee the notes being registered. (4) Pursuant to Rule 457(n) under the Securities Act of 1933, as amended, no additional registration fee is due for the guarantees.</ffd:OfferingNote>
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