<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:xlink="http://www.w3.org/1999/xlink">
    <link:schemaRef xlink:href="ftci-20261104.xsd" xlink:type="simple"/>
    <context id="C_00cec599-b714-4f71-b98b-966fa2cfa80a">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001828161</identifier>
        </entity>
        <period>
            <startDate>2026-11-04</startDate>
            <endDate>2026-11-04</endDate>
        </period>
    </context>
    <dei:AmendmentFlag
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_6b849beb-7e53-49b4-8e66-7dbf49d3a87e">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_ad17606a-9791-42d9-a31f-6f00d57b7c9d">0001828161</dei:EntityCentralIndexKey>
    <dei:DocumentType
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_e922311a-1e23-4ff0-a188-c38ca8e9844e">8-K</dei:DocumentType>
    <dei:DocumentPeriodEndDate
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_11d81f18-8cf1-4139-88e1-89d90addbd20">2026-11-04</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_c8d46ac7-cd72-479b-a9ce-5074aaa5ae8b">FTC Solar, Inc.</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_d5fe1c70-45cd-4709-b43d-b96eb10944f5">DE</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_92f66953-8bf8-4c6f-bc29-a54d10b5c4e3">001-40350</dei:EntityFileNumber>
    <dei:EntityTaxIdentificationNumber
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_2d6aac41-b42a-4bd1-b51b-dce1dd893dd0">81-4816270</dei:EntityTaxIdentificationNumber>
    <dei:EntityAddressAddressLine1
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_2edce3ea-8bcc-497e-83fb-08eb13daa27f">10900 Stonelake Blvd</dei:EntityAddressAddressLine1>
    <dei:EntityAddressAddressLine2
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_d5e13576-6be6-4f9a-a6fe-313ae987d4a6">Suite 100</dei:EntityAddressAddressLine2>
    <dei:EntityAddressAddressLine3
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_4c05d71c-4694-4f3b-909a-81afda4ad999">Quarry Oaks II Building</dei:EntityAddressAddressLine3>
    <dei:EntityAddressCityOrTown
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_60e5f68c-981f-4bd7-9d18-8dbc5ffd8aee">Austin</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_d4940ec2-283e-41e6-8729-e05719d878d8">TX</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_78b525ab-752b-4826-b341-be6b558e7d51">78759</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_81834ece-92b6-4957-88ab-873a71642bf9">512</dei:CityAreaCode>
    <dei:LocalPhoneNumber
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_ef5476d0-fd24-45dc-8964-cfd28eb62acd">481-4271</dei:LocalPhoneNumber>
    <dei:WrittenCommunications
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_b491505e-cc10-408a-a6f8-13480d2b600b">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_1c7d6610-0047-499e-b09a-1e852a3f1616">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_3914f875-c380-4f92-8e6d-ff384df1fea2">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_15196508-3134-48d2-a543-eba597fef6cd">false</dei:PreCommencementIssuerTenderOffer>
    <dei:Security12bTitle
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_4ab58d8d-d5a9-48f9-9fd8-9155fa0e30ce">Common Stock, $0.0001 par value</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_1442c75e-c1a4-4c98-9c72-0cf6289b1cd8">FTCI</dei:TradingSymbol>
    <dei:SecurityExchangeName
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_23c64e40-ec42-4c38-a25c-33c5771290c7">NASDAQ</dei:SecurityExchangeName>
    <dei:EntityEmergingGrowthCompany
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_0c875a1b-15af-46a1-8a3d-c69ff21bdeca">true</dei:EntityEmergingGrowthCompany>
    <dei:EntityExTransitionPeriod
      contextRef="C_00cec599-b714-4f71-b98b-966fa2cfa80a"
      id="F_5ec4a551-69b0-4466-ba10-12b1e1a583f4">false</dei:EntityExTransitionPeriod>
</xbrl>
