<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.25.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>291</ContextCount>
  <ElementCount>300</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>111</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>7</UnitCount>
  <MyReports>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>100000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>100010 - Statement - Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/StatementCondensedConsolidatedBalanceSheets</Role>
      <ShortName>Condensed Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>100020 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/StatementCondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>100030 - Statement - Condensed Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperations</Role>
      <ShortName>Condensed Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>100040 - Statement - Condensed Consolidated Statements of Comprehensive Loss</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/StatementCondensedConsolidatedStatementsOfComprehensiveLoss</Role>
      <ShortName>Condensed Consolidated Statements of Comprehensive Loss</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>100050 - Statement - Condensed Consolidated Statements of Stockholders' Deficit</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/StatementCondensedConsolidatedStatementsOfStockholdersDeficit</Role>
      <ShortName>Condensed Consolidated Statements of Stockholders' Deficit</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>100060 - Statement - Condensed Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/StatementCondensedConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>995410 - Disclosure - Pay vs Performance Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/PvpDisclosure</Role>
      <ShortName>Pay vs Performance Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.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>9</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>995455 - Disclosure - Organization and Liquidity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureOrganizationAndLiquidity</Role>
      <ShortName>Organization and Liquidity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>995465 - Disclosure - Summary of Significant Accounting Policies and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentation</Role>
      <ShortName>Summary of Significant Accounting Policies and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>995485 - Disclosure - Disaggregation of Revenue</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDisaggregationOfRevenue</Role>
      <ShortName>Disaggregation of Revenue</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>995495 - Disclosure - Fair Value of Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurements</Role>
      <ShortName>Fair Value of Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>995505 - Disclosure - Balance Sheet Components</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponents</Role>
      <ShortName>Balance Sheet Components</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>995515 - Disclosure - Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebt</Role>
      <ShortName>Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>995525 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>995535 - Disclosure - Common Stock</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStock</Role>
      <ShortName>Common Stock</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>995545 - Disclosure - Common Stock Warrants</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockWarrants</Role>
      <ShortName>Common Stock Warrants</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>995555 - Disclosure - Stock-Based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockBasedCompensation</Role>
      <ShortName>Stock-Based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>995565 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>995575 - Disclosure - Employee Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEmployeeBenefitPlans</Role>
      <ShortName>Employee Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>995585 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureRelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>995595 - Disclosure - Entity-Wide Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEntitywideInformation</Role>
      <ShortName>Entity-Wide Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>995605 - Disclosure - Net Income (Loss) Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureNetIncomeLossPerShare</Role>
      <ShortName>Net Income (Loss) Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>995615 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>995625 - Disclosure - Summary of Significant Accounting Policies and Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentationPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies and Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentation</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>995635 - Disclosure - Summary of Significant Accounting Policies and Basis of Presentation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentationTables</Role>
      <ShortName>Summary of Significant Accounting Policies and Basis of Presentation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentation</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>995655 - Disclosure - Disaggregation of Revenue (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDisaggregationOfRevenueTables</Role>
      <ShortName>Disaggregation of Revenue (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDisaggregationOfRevenue</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>995665 - Disclosure - Fair Value of Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurementsTables</Role>
      <ShortName>Fair Value of Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurements</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>995675 - Disclosure - Balance Sheet Components (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponentsTables</Role>
      <ShortName>Balance Sheet Components (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponents</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>995685 - Disclosure - Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebtTables</Role>
      <ShortName>Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebt</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>995695 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommitmentsAndContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommitmentsAndContingencies</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>995705 - Disclosure - Common Stock (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockTables</Role>
      <ShortName>Common Stock (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStock</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>995715 - Disclosure - Common Stock Warrants (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockWarrantsTables</Role>
      <ShortName>Common Stock Warrants (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockWarrants</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>995725 - Disclosure - Stock-Based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockBasedCompensationTables</Role>
      <ShortName>Stock-Based Compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockBasedCompensation</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>995735 - Disclosure - Employee Benefit Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEmployeeBenefitPlansTables</Role>
      <ShortName>Employee Benefit Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEmployeeBenefitPlans</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>995745 - Disclosure - Related Party Transactions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureRelatedPartyTransactionsTables</Role>
      <ShortName>Related Party Transactions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureRelatedPartyTransactions</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>995755 - Disclosure - Entity-Wide Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEntitywideInformationTables</Role>
      <ShortName>Entity-Wide Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEntitywideInformation</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>995765 - Disclosure - Net Income (Loss) Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureNetIncomeLossPerShareTables</Role>
      <ShortName>Net Income (Loss) Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureNetIncomeLossPerShare</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>995775 - Disclosure - Organization and Liquidity - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureOrganizationAndLiquidityAdditionalInformationDetails</Role>
      <ShortName>Organization and Liquidity - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>995785 - Disclosure - Summary of Significant Accounting Policies and Basis of Presentation - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentationAdditionalInformationDetails</Role>
      <ShortName>Summary of Significant Accounting Policies and Basis of Presentation - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>995795 - Disclosure - Summary of Significant Accounting Policies and Basis of Presentation - Schedule of Net Revenues and Accounts Receivable Concentration (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAndBasisOfPresentationScheduleOfNetRevenuesAndAccountsReceivableConcentrationDetails</Role>
      <ShortName>Summary of Significant Accounting Policies and Basis of Presentation - Schedule of Net Revenues and Accounts Receivable Concentration (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>995835 - Disclosure - Reverse Recapitalization - Schedule of outstanding common stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureReverseRecapitalizationScheduleOfOutstandingCommonStockDetails</Role>
      <ShortName>Reverse Recapitalization - Schedule of outstanding common stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>995865 - Disclosure - Reverse Recapitalization -Private Warrants and Public warrants - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureReverseRecapitalizationPrivateWarrantsAndPublicWarrantsAdditionalInformationDetails</Role>
      <ShortName>Reverse Recapitalization -Private Warrants and Public warrants - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>995885 - Disclosure - Disaggregation of Revenue - Schedule of Net Revenues Categorized by Customer Location (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDisaggregationOfRevenueScheduleOfNetRevenuesCategorizedByCustomerLocationDetails</Role>
      <ShortName>Disaggregation of Revenue - Schedule of Net Revenues Categorized by Customer Location (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>995895 - Disclosure - Disaggregation of Revenue - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDisaggregationOfRevenueAdditionalInformationDetails</Role>
      <ShortName>Disaggregation of Revenue - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>995905 - Disclosure - Fair Value of Measurements - Schedule of Financial Instruments are Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurementsScheduleOfFinancialInstrumentsAreMeasuredAtFairValueOnARecurringBasisDetails</Role>
      <ShortName>Fair Value of Measurements - Schedule of Financial Instruments are Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>995915 - Disclosure - Fair Value of Measurements - Schedule of Valuation Techniques and Inputs Used in the Fair Value Measurement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurementsScheduleOfValuationTechniquesAndInputsUsedInTheFairValueMeasurementDetails</Role>
      <ShortName>Fair Value of Measurements - Schedule of Valuation Techniques and Inputs Used in the Fair Value Measurement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>995925 - Disclosure - Fair Value of Measurements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurementsAdditionalInformationDetails</Role>
      <ShortName>Fair Value of Measurements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>995935 - Disclosure - Fair Value of Measurements - Summary of Changes in the Fair Value of the Company's Level 3 Financial Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureFairValueOfMeasurementsSummaryOfChangesInTheFairValueOfTheCompanysLevel3FinancialLiabilitiesDetails</Role>
      <ShortName>Fair Value of Measurements - Summary of Changes in the Fair Value of the Company's Level 3 Financial Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>995945 - Disclosure - Balance Sheet Components - Schedule of Inventory (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponentsScheduleOfInventoryDetails</Role>
      <ShortName>Balance Sheet Components - Schedule of Inventory (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>995955 - Disclosure - Balance Sheet Components - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponentsAdditionalInformationDetails</Role>
      <ShortName>Balance Sheet Components - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>995965 - Disclosure - Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponentsScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetails</Role>
      <ShortName>Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>995975 - Disclosure - Balance Sheet Components - Schedule of Accrued and Other Current Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureBalanceSheetComponentsScheduleOfAccruedAndOtherCurrentLiabilitiesDetails</Role>
      <ShortName>Balance Sheet Components - Schedule of Accrued and Other Current Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>995985 - Disclosure - Debt - Schedule of Outstanding Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebtScheduleOfOutstandingDebtDetails</Role>
      <ShortName>Debt - Schedule of Outstanding Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>995995 - Disclosure - Debt - Schedule of Expected Future Minimum Principal Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebtScheduleOfExpectedFutureMinimumPrincipalPaymentsDetails</Role>
      <ShortName>Debt - Schedule of Expected Future Minimum Principal Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>996005 - Disclosure - Debt - Convertible Promissory Notes - Additional Information (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebtConvertiblePromissoryNotesAdditionalInformationDetails</Role>
      <ShortName>Debt - Convertible Promissory Notes - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>996015 - Disclosure - Debt - Borrowings Pursuant to Term Loan and Security Agreements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureDebtBorrowingsPursuantToTermLoanAndSecurityAgreementsAdditionalInformationDetails</Role>
      <ShortName>Debt - Borrowings Pursuant to Term Loan and Security Agreements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>996025 - Disclosure - Commitments and Contingencies - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetails</Role>
      <ShortName>Commitments and Contingencies - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>996035 - Disclosure - Commitments and Contingencies - Summary of Carrying Amounts Related to Collateral Provided to Anapass, Inc (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommitmentsAndContingenciesSummaryOfCarryingAmountsRelatedToCollateralProvidedToAnapassIncDetails</Role>
      <ShortName>Commitments and Contingencies - Summary of Carrying Amounts Related to Collateral Provided to Anapass, Inc (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>996045 - Disclosure - Common Stock - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockAdditionalInformationDetails</Role>
      <ShortName>Common Stock - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>996065 - Disclosure - Common Stock - Summary of Reserved Shares of Common Stock for Issuance (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockSummaryOfReservedSharesOfCommonStockForIssuanceDetails</Role>
      <ShortName>Common Stock - Summary of Reserved Shares of Common Stock for Issuance (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>996075 - Disclosure - Common Stock Warrants - Summary of Warrants to Purchase Shares of Common Stock Outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureCommonStockWarrantsSummaryOfWarrantsToPurchaseSharesOfCommonStockOutstandingDetails</Role>
      <ShortName>Common Stock Warrants - Summary of Warrants to Purchase Shares of Common Stock Outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>996085 - Disclosure - Stock-Based Compensation - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockbasedCompensationAdditionalInformationDetails</Role>
      <ShortName>Stock-Based Compensation - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>996095 - Disclosure - Stock-Based Compensation - Summary of Stock Options Outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockbasedCompensationSummaryOfStockOptionsOutstandingDetails</Role>
      <ShortName>Stock-Based Compensation - Summary of Stock Options Outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>996105 - Disclosure - Stock-Based Compensation - Summary of RSUs Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockbasedCompensationSummaryOfRsusActivityDetails</Role>
      <ShortName>Stock-Based Compensation - Summary of RSUs Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>996115 - Disclosure - Stock-Based Compensation - Restricted Stock Units - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockbasedCompensationRestrictedStockUnitsAdditionalInformationDetails</Role>
      <ShortName>Stock-Based Compensation - Restricted Stock Units - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>996125 - Disclosure - Stock-Based Compensation - Summary of Stock-Based Compensation Included in Consolidated Statements of Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureStockbasedCompensationSummaryOfStockbasedCompensationIncludedInConsolidatedStatementsOfOperationsDetails</Role>
      <ShortName>Stock-Based Compensation - Summary of Stock-Based Compensation Included in Consolidated Statements of Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>996135 - Disclosure - Income Taxes - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetails</Role>
      <ShortName>Income Taxes - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>996145 - Disclosure - Employee Benefit Plans - Summary of Net Liability for Severance Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEmployeeBenefitPlansSummaryOfNetLiabilityForSeverancePaymentsDetails</Role>
      <ShortName>Employee Benefit Plans - Summary of Net Liability for Severance Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>996155 - Disclosure - Related Party Transactions - Summary of Balances and Transactions With Related Parties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureRelatedPartyTransactionsSummaryOfBalancesAndTransactionsWithRelatedPartiesDetails</Role>
      <ShortName>Related Party Transactions - Summary of Balances and Transactions With Related Parties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>996165 - Disclosure - Related Party Transactions - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformationDetails</Role>
      <ShortName>Related Party Transactions - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>996175 - Disclosure - Entity-Wide Information - Summary of Long-lived Assets by Geographic Region (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureEntitywideInformationSummaryOfLonglivedAssetsByGeographicRegionDetails</Role>
      <ShortName>Entity-Wide Information - Summary of Long-lived Assets by Geographic Region (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>996185 - Disclosure - Net Income (Loss) Per Share - Schedule of Potentially Dilutive Common Stock Equivalents Excluded From Computation of Diluted Net Income (Loss) Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureNetIncomeLossPerShareScheduleOfPotentiallyDilutiveCommonStockEquivalentsExcludedFromComputationOfDilutedNetIncomeLossPerShare</Role>
      <ShortName>Net Income (Loss) Per Share - Schedule of Potentially Dilutive Common Stock Equivalents Excluded From Computation of Diluted Net Income (Loss) Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureNetIncomeLossPerShareTables</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="gcts-20250331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>996195 - Disclosure - Subsequent Events - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://investors.gctsemi.com/20250331/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetails</Role>
      <ShortName>Subsequent Events - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</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="gcts-20250331.htm">gcts-20250331.htm</File>
    <File>gcts-20250331.xsd</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="656">http://fasb.org/us-gaap/2024</BaseTaxonomy>
    <BaseTaxonomy items="33">http://xbrl.sec.gov/dei/2024</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2024</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>false</HasPresentationLinkbase>
  <HasCalculationLinkbase>false</HasCalculationLinkbase>
</FilingSummary>
