<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>193</ContextCount>
  <ElementCount>338</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>69</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>7</UnitCount>
  <MyReports>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - CONSOLIDATED INTERIM STATEMENTS OF OPERATIONS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMSTATEMENTSOFOPERATIONSUNAUDITED</Role>
      <ShortName>CONSOLIDATED INTERIM STATEMENTS OF OPERATIONS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - CONSOLIDATED INTERIM STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMSTATEMENTSOFCOMPREHENSIVEINCOMEUNAUDITED</Role>
      <ShortName>CONSOLIDATED INTERIM STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - CONSOLIDATED INTERIM BALANCE SHEETS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMBALANCESHEETSUNAUDITED</Role>
      <ShortName>CONSOLIDATED INTERIM BALANCE SHEETS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - CONSOLIDATED INTERIM BALANCE SHEETS (UNAUDITED) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMBALANCESHEETSUNAUDITEDParenthetical</Role>
      <ShortName>CONSOLIDATED INTERIM BALANCE SHEETS (UNAUDITED) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Statement - CONSOLIDATED INTERIM STATEMENTS OF CASH FLOWS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMSTATEMENTSOFCASHFLOWSUNAUDITED</Role>
      <ShortName>CONSOLIDATED INTERIM STATEMENTS OF CASH FLOWS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Statement - CONSOLIDATED INTERIM STATEMENTS OF CASH FLOWS (UNAUDITED) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMSTATEMENTSOFCASHFLOWSUNAUDITEDParenthetical</Role>
      <ShortName>CONSOLIDATED INTERIM STATEMENTS OF CASH FLOWS (UNAUDITED) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Statement - CONSOLIDATED INTERIM STATEMENTS OF EQUITY (DEFICIT) (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CONSOLIDATEDINTERIMSTATEMENTSOFEQUITYDEFICITUNAUDITED</Role>
      <ShortName>CONSOLIDATED INTERIM STATEMENTS OF EQUITY (DEFICIT) (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Disclosure - Background and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/BackgroundandBasisofPresentation</Role>
      <ShortName>Background and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SummaryofSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - Revenue Recognition and Contracts with Customers</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/RevenueRecognitionandContractswithCustomers</Role>
      <ShortName>Revenue Recognition and Contracts with Customers</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - Research, Development and Engineering</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/ResearchDevelopmentandEngineering</Role>
      <ShortName>Research, Development and Engineering</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - Accounts, Notes and Other Receivables-Net</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/AccountsNotesandOtherReceivablesNet</Role>
      <ShortName>Accounts, Notes and Other Receivables-Net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - Factoring and Notes Receivable</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/FactoringandNotesReceivable</Role>
      <ShortName>Factoring and Notes Receivable</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - Inventories-Net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/InventoriesNet</Role>
      <ShortName>Inventories-Net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - Other Current Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherCurrentAssets</Role>
      <ShortName>Other Current Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952167 - Disclosure - Other Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherAssets</Role>
      <ShortName>Other Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952168 - Disclosure - Supplier Financing</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SupplierFinancing</Role>
      <ShortName>Supplier Financing</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952169 - Disclosure - Accrued Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccruedLiabilities</Role>
      <ShortName>Accrued Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952170 - Disclosure - Other Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherLiabilities</Role>
      <ShortName>Other Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/Leases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - Long-term Debt and Credit Agreements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LongtermDebtandCreditAgreements</Role>
      <ShortName>Long-term Debt and Credit Agreements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/Equity</Role>
      <ShortName>Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - Financial Instruments and Fair Value Measures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasures</Role>
      <ShortName>Financial Instruments and Fair Value Measures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - Accumulated Other Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccumulatedOtherComprehensiveIncome</Role>
      <ShortName>Accumulated Other Comprehensive Income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - Earnings Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/EarningsPerShare</Role>
      <ShortName>Earnings Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9952177 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9952178 - Disclosure - Pension Benefits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/PensionBenefits</Role>
      <ShortName>Pension Benefits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9952179 - Disclosure - Segments and Concentrations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SegmentsandConcentrations</Role>
      <ShortName>Segments and Concentrations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9952180 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.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>32</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SummaryofSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/SummaryofSignificantAccountingPolicies</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Revenue Recognition and Contracts with Customers (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/RevenueRecognitionandContractswithCustomersTables</Role>
      <ShortName>Revenue Recognition and Contracts with Customers (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/RevenueRecognitionandContractswithCustomers</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Research, Development and Engineering (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/ResearchDevelopmentandEngineeringTables</Role>
      <ShortName>Research, Development and Engineering (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/ResearchDevelopmentandEngineering</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/IncomeTaxes</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Accounts, Notes and Other Receivables-Net (Tables)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/AccountsNotesandOtherReceivablesNetTables</Role>
      <ShortName>Accounts, Notes and Other Receivables-Net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/AccountsNotesandOtherReceivablesNet</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Factoring and Notes Receivable (Tables)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/FactoringandNotesReceivableTables</Role>
      <ShortName>Factoring and Notes Receivable (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/FactoringandNotesReceivable</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Inventories-Net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/InventoriesNetTables</Role>
      <ShortName>Inventories-Net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/InventoriesNet</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Other Current Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherCurrentAssetsTables</Role>
      <ShortName>Other Current Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/OtherCurrentAssets</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Other Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherAssetsTables</Role>
      <ShortName>Other Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/OtherAssets</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Supplier Financing (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SupplierFinancingTables</Role>
      <ShortName>Supplier Financing (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/SupplierFinancing</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Accrued Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccruedLiabilitiesTables</Role>
      <ShortName>Accrued Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/AccruedLiabilities</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Other Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherLiabilitiesTables</Role>
      <ShortName>Other Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/OtherLiabilities</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/Leases</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Long-term Debt and Credit Agreements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LongtermDebtandCreditAgreementsTables</Role>
      <ShortName>Long-term Debt and Credit Agreements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/LongtermDebtandCreditAgreements</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/EquityTables</Role>
      <ShortName>Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/Equity</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Financial Instruments and Fair Value Measures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasuresTables</Role>
      <ShortName>Financial Instruments and Fair Value Measures (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasures</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Accumulated Other Comprehensive Income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccumulatedOtherComprehensiveIncomeTables</Role>
      <ShortName>Accumulated Other Comprehensive Income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/AccumulatedOtherComprehensiveIncome</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Earnings Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/EarningsPerShareTables</Role>
      <ShortName>Earnings Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/EarningsPerShare</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CommitmentsandContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/CommitmentsandContingencies</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Pension Benefits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/PensionBenefitsTables</Role>
      <ShortName>Pension Benefits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/PensionBenefits</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Segments and Concentrations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SegmentsandConcentrationsTables</Role>
      <ShortName>Segments and Concentrations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/SegmentsandConcentrations</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Background and Basis of Presentation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/BackgroundandBasisofPresentationDetails</Role>
      <ShortName>Background and Basis of Presentation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/BackgroundandBasisofPresentation</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Revenue Recognition and Contracts with Customers - Summary of Contract Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/RevenueRecognitionandContractswithCustomersSummaryofContractAssetsandLiabilitiesDetails</Role>
      <ShortName>Revenue Recognition and Contracts with Customers - Summary of Contract Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Research, Development and Engineering - Summary of Research, Development &amp; Engineering Activities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/ResearchDevelopmentandEngineeringSummaryofResearchDevelopmentEngineeringActivitiesDetails</Role>
      <ShortName>Research, Development and Engineering - Summary of Research, Development &amp; Engineering Activities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Research, Development and Engineering - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/ResearchDevelopmentandEngineeringAdditionalInformationDetails</Role>
      <ShortName>Research, Development and Engineering - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Income Taxes - Tax Expense (Benefit) and Effective Tax Rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/IncomeTaxesTaxExpenseBenefitandEffectiveTaxRateDetails</Role>
      <ShortName>Income Taxes - Tax Expense (Benefit) and Effective Tax Rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Income Taxes - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/IncomeTaxesAdditionalInformationDetails</Role>
      <ShortName>Income Taxes - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Accounts, Notes and Other Receivables-Net - Schedule of Accounts, Notes and Other Receivables-Net (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/AccountsNotesandOtherReceivablesNetScheduleofAccountsNotesandOtherReceivablesNetDetails</Role>
      <ShortName>Accounts, Notes and Other Receivables-Net - Schedule of Accounts, Notes and Other Receivables-Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Accounts, Notes and Other Receivables-Net - Additional Information (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/AccountsNotesandOtherReceivablesNetAdditionalInformationDetails</Role>
      <ShortName>Accounts, Notes and Other Receivables-Net - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Factoring and Notes Receivable - Disclosure of Detailed Information about Trade Receivables (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/FactoringandNotesReceivableDisclosureofDetailedInformationaboutTradeReceivablesDetails</Role>
      <ShortName>Factoring and Notes Receivable - Disclosure of Detailed Information about Trade Receivables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Factoring and Notes Receivable - Additional Information (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/FactoringandNotesReceivableAdditionalInformationDetails</Role>
      <ShortName>Factoring and Notes Receivable - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Factoring and Notes Receivable - Disclosure of Detailed Information about Guaranteed Bank Notes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.garrettmotion.com/role/FactoringandNotesReceivableDisclosureofDetailedInformationaboutGuaranteedBankNotesDetails</Role>
      <ShortName>Factoring and Notes Receivable - Disclosure of Detailed Information about Guaranteed Bank Notes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - Inventories-Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/InventoriesNetDetails</Role>
      <ShortName>Inventories-Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/InventoriesNetTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - Other Current Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherCurrentAssetsDetails</Role>
      <ShortName>Other Current Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/OtherCurrentAssetsTables</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - Other Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherAssetsDetails</Role>
      <ShortName>Other Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/OtherAssetsTables</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - Supplier Financing - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SupplierFinancingAdditionalInformationDetails</Role>
      <ShortName>Supplier Financing - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - Supplier Financing - Supplier Finance Program (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SupplierFinancingSupplierFinanceProgramDetails</Role>
      <ShortName>Supplier Financing - Supplier Finance Program (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - Accrued Liabilities - Summary of Accrued Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccruedLiabilitiesSummaryofAccruedLiabilitiesDetails</Role>
      <ShortName>Accrued Liabilities - Summary of Accrued Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - Accrued Liabilities - Summary of Expenses Related to the Repositioning Accruals (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccruedLiabilitiesSummaryofExpensesRelatedtotheRepositioningAccrualsDetails</Role>
      <ShortName>Accrued Liabilities - Summary of Expenses Related to the Repositioning Accruals (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - Other Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/OtherLiabilitiesDetails</Role>
      <ShortName>Other Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/OtherLiabilitiesTables</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - Leases - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LeasesAdditionalInformationDetails</Role>
      <ShortName>Leases - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>9955552 - Disclosure - Leases - Summary of Components of Lease Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LeasesSummaryofComponentsofLeaseExpenseDetails</Role>
      <ShortName>Leases - Summary of Components of Lease Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>9955553 - Disclosure - Leases - Summary of Supplemental Cash Flow Information Related to Operating Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LeasesSummaryofSupplementalCashFlowInformationRelatedtoOperatingLeasesDetails</Role>
      <ShortName>Leases - Summary of Supplemental Cash Flow Information Related to Operating Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>9955554 - Disclosure - Leases - Summary of Supplemental Balance Sheet Information Related to Operating Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LeasesSummaryofSupplementalBalanceSheetInformationRelatedtoOperatingLeasesDetails</Role>
      <ShortName>Leases - Summary of Supplemental Balance Sheet Information Related to Operating Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>9955555 - Disclosure - Leases - Schedule of Maturities of Operating Lease Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LeasesScheduleofMaturitiesofOperatingLeaseLiabilitiesDetails</Role>
      <ShortName>Leases - Schedule of Maturities of Operating Lease Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>9955556 - Disclosure - Long-term Debt and Credit Agreements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LongtermDebtandCreditAgreementsAdditionalInformationDetails</Role>
      <ShortName>Long-term Debt and Credit Agreements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>9955557 - Disclosure - Long-term Debt and Credit Agreements - Schedule of Principal Outstanding And Carrying Amount of Long term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LongtermDebtandCreditAgreementsScheduleofPrincipalOutstandingAndCarryingAmountofLongtermDebtDetails</Role>
      <ShortName>Long-term Debt and Credit Agreements - Schedule of Principal Outstanding And Carrying Amount of Long term Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>9955558 - Disclosure - Long-term Debt and Credit Agreements - Schedule of maturities of long-term debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/LongtermDebtandCreditAgreementsScheduleofmaturitiesoflongtermdebtDetails</Role>
      <ShortName>Long-term Debt and Credit Agreements - Schedule of maturities of long-term debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>9955559 - Disclosure - Equity - Summary of cash dividend paid (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/EquitySummaryofcashdividendpaidDetails</Role>
      <ShortName>Equity - Summary of cash dividend paid (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>9955560 - Disclosure - Equity - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/EquityAdditionalInformationDetails</Role>
      <ShortName>Equity - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>9955561 - Disclosure - Financial Instruments and Fair Value Measures - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasuresAdditionalInformationDetails</Role>
      <ShortName>Financial Instruments and Fair Value Measures - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>9955562 - Disclosure - Financial Instruments and Fair Value Measures - Summary of Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasuresSummaryofFinancialAssetsandLiabilitiesAccountedforatFairValueonRecurringBasisDetails</Role>
      <ShortName>Financial Instruments and Fair Value Measures - Summary of Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>9955563 - Disclosure - Financial Instruments and Fair Value Measures - Effect of derivatives on Income Statement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasuresEffectofderivativesonIncomeStatementDetails</Role>
      <ShortName>Financial Instruments and Fair Value Measures - Effect of derivatives on Income Statement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>9955564 - Disclosure - Financial Instruments and Fair Value Measures - Derivatives not designated (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasuresDerivativesnotdesignatedDetails</Role>
      <ShortName>Financial Instruments and Fair Value Measures - Derivatives not designated (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>9955565 - Disclosure - Financial Instruments and Fair Value Measures - Summary of Financial Assets and Liabilities Not Carried at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/FinancialInstrumentsandFairValueMeasuresSummaryofFinancialAssetsandLiabilitiesNotCarriedatFairValueDetails</Role>
      <ShortName>Financial Instruments and Fair Value Measures - Summary of Financial Assets and Liabilities Not Carried at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>9955566 - Disclosure - Accumulated Other Comprehensive Income - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccumulatedOtherComprehensiveIncomeSummaryofChangesinAccumulatedOtherComprehensiveIncomeLossDetails</Role>
      <ShortName>Accumulated Other Comprehensive Income - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>9955567 - Disclosure - Accumulated Other Comprehensive Income - Reclassification Out of Accumulated Other Comprehensive Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/AccumulatedOtherComprehensiveIncomeReclassificationOutofAccumulatedOtherComprehensiveIncomeDetails</Role>
      <ShortName>Accumulated Other Comprehensive Income - Reclassification Out of Accumulated Other Comprehensive Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>9955568 - Disclosure - Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/EarningsPerShareDetails</Role>
      <ShortName>Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/EarningsPerShareTables</ParentRole>
      <Position>90</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>9955569 - Disclosure - Commitments and Contingencies - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CommitmentsandContingenciesAdditionalInformationDetails</Role>
      <ShortName>Commitments and Contingencies - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>9955570 - Disclosure - Commitments and Contingencies - Summary Information Concerning our Recorded Obligations for Product Warranties and Product Performance Guarantees (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/CommitmentsandContingenciesSummaryInformationConcerningourRecordedObligationsforProductWarrantiesandProductPerformanceGuaranteesDetails</Role>
      <ShortName>Commitments and Contingencies - Summary Information Concerning our Recorded Obligations for Product Warranties and Product Performance Guarantees (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>9955571 - Disclosure - Pension Benefits - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/PensionBenefitsAdditionalInformationDetails</Role>
      <ShortName>Pension Benefits - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>9955572 - Disclosure - Pension Benefits - Summary of Net Periodic Benefit Cost (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/PensionBenefitsSummaryofNetPeriodicBenefitCostDetails</Role>
      <ShortName>Pension Benefits - Summary of Net Periodic Benefit Cost (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>9955573 - Disclosure - Segments and Concentrations - Summary of Net Sales by Region and Channel (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SegmentsandConcentrationsSummaryofNetSalesbyRegionandChannelDetails</Role>
      <ShortName>Segments and Concentrations - Summary of Net Sales by Region and Channel (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>9955574 - Disclosure - Segments and Concentrations - Segment information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SegmentsandConcentrationsSegmentinformationDetails</Role>
      <ShortName>Segments and Concentrations - Segment information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>9955575 - Disclosure - Segments and Concentrations - Additional information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SegmentsandConcentrationsAdditionalinformationDetails</Role>
      <ShortName>Segments and Concentrations - Additional information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="gtx-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>9955576 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.garrettmotion.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.garrettmotion.com/role/SubsequentEvents</ParentRole>
      <Position>98</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="gtx-20260331.htm">gtx-20260331.htm</File>
    <File>gtx-20260331.xsd</File>
    <File>gtx-20260331_cal.xml</File>
    <File>gtx-20260331_def.xml</File>
    <File>gtx-20260331_lab.xml</File>
    <File>gtx-20260331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>gtx-20260331_g1.jpg</File>
    <File>gtx-20260331_g2.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="2">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="732">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="35">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="19">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>