<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2025"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:xlink="http://www.w3.org/1999/xlink">
    <link:schemaRef xlink:href="tcrt-20260302.xsd" xlink:type="simple"/>
    <context id="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001107421</identifier>
        </entity>
        <period>
            <startDate>2026-03-02</startDate>
            <endDate>2026-03-02</endDate>
        </period>
    </context>
    <dei:AmendmentFlag
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_571389b4-f72d-4891-99f0-c9ae87c4bc6e">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_fe4c2bd5-4225-40f2-b744-734620b04daf">0001107421</dei:EntityCentralIndexKey>
    <dei:DocumentType
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_669cbc71-5d7e-446e-a75f-cbc7301ebbd3">8-K</dei:DocumentType>
    <dei:DocumentPeriodEndDate
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_fb787efb-c7ed-484c-afda-8f3e2ede1a95">2026-05-18</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_d9dfbd69-6099-4a37-a99d-bf43f0ddbb7c">Alaunos Therapeutics, Inc.</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_97312b63-3006-4a6c-bcf7-76be149dea79">DE</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_bd9fc472-5a7b-4380-9104-7d8fd0b57a25">001-33038</dei:EntityFileNumber>
    <dei:EntityTaxIdentificationNumber
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_a5d7dd7e-4b54-42a9-abcc-b4198e480e2b">84-1475642</dei:EntityTaxIdentificationNumber>
    <dei:EntityAddressAddressLine1
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_6b0c3ce1-6c96-4e4a-a30e-1fdff6b17699">501 E. Las Olas Blvd.</dei:EntityAddressAddressLine1>
    <dei:EntityAddressAddressLine2
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_3efdd7df-e6be-42cc-8f50-7c4e27e39a27">Suite 300</dei:EntityAddressAddressLine2>
    <dei:EntityAddressCityOrTown
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_c66d07e8-8ffb-47a7-a225-7fd0774fd144">Fort Lauderdale</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_570e8a7b-6dcf-411a-aba9-ea677e5093cc">FL</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_5ca586c1-fb79-42d2-9635-f5c9653449c2">33301</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_8acea5e0-8c7c-43a6-8ab7-2035aa273367">346</dei:CityAreaCode>
    <dei:LocalPhoneNumber
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_6b86d89d-d83e-499e-b7f2-7591961f5705">355-4099</dei:LocalPhoneNumber>
    <dei:WrittenCommunications
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_cc04b6cd-d66c-43a8-8aa2-bd9aadb9987c">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_ff40e363-6cf9-4f2d-9742-a9c2e1e781cc">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_5ee2cd0f-c565-44b5-b6d5-e98f6ec7d0bf">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_cc44333b-7ae6-4260-8c3a-8735b1fdd9c7">false</dei:PreCommencementIssuerTenderOffer>
    <dei:Security12bTitle
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_e0aae60f-e95d-464b-8d4f-972083867290">Common Stock, par value $0.001 per share</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_dc058910-dd80-4e24-860d-e8638ad377e0">TCRT</dei:TradingSymbol>
    <dei:SecurityExchangeName
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_091e06d3-4496-49e0-ad5e-4f9de67cefd0">NASDAQ</dei:SecurityExchangeName>
    <dei:EntityEmergingGrowthCompany
      contextRef="C_a966c6ed-c6cb-4ebd-8565-4b91c36e6bc9"
      id="F_31e43f90-1f6a-49da-8533-b20b49f168e7">false</dei:EntityEmergingGrowthCompany>
</xbrl>
