<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.7.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>302</ContextCount>
  <ElementCount>286</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>112</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>13</UnitCount>
  <MyReports>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1002000 - Statement - Condensed Consolidated Income Statements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CondensedConsolidatedIncomeStatements</Role>
      <ShortName>Condensed Consolidated Income Statements</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1003000 - Statement - Condensed Consolidated Statements of Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CondensedConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>Condensed Consolidated Statements of Comprehensive Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1004000 - Statement - Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CondensedConsolidatedBalanceSheets</Role>
      <ShortName>Condensed Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1004001 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1005000 - Statement - Condensed Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CondensedConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1006000 - Statement - Condensed Consolidated Statements of Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CondensedConsolidatedStatementsOfEquity</Role>
      <ShortName>Condensed Consolidated Statements of Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Nature of Operations and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/NatureOfOperationsAndBasisOfPresentation</Role>
      <ShortName>Nature of Operations and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2105100 - Disclosure - Disposition of Business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/DispositionOfBusiness</Role>
      <ShortName>Disposition of Business</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Marketable Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/MarketableSecurities</Role>
      <ShortName>Marketable Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2108100 - Disclosure - GM Financial Receivables</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/GmFinancialReceivables</Role>
      <ShortName>GM Financial Receivables</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - Inventories</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/Inventories</Role>
      <ShortName>Inventories</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2115100 - Disclosure - Equipment on Operating Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EquipmentOnOperatingLeases</Role>
      <ShortName>Equipment on Operating Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2122100 - Disclosure - Equity In Net Assets of Nonconsolidated Affiliates</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EquityInNetAssetsOfNonconsolidatedAffiliates</Role>
      <ShortName>Equity In Net Assets of Nonconsolidated Affiliates</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2127100 - Disclosure - Variable Interest Entities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/VariableInterestEntities</Role>
      <ShortName>Variable Interest Entities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2132100 - Disclosure - Automotive and GM Financial Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/AutomotiveAndGmFinancialDebt</Role>
      <ShortName>Automotive and GM Financial Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2133100 - Disclosure - Derivative Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/DerivativeFinancialInstruments</Role>
      <ShortName>Derivative Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2135100 - Disclosure - Product Warranty and Related Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/ProductWarrantyAndRelatedLiabilities</Role>
      <ShortName>Product Warranty and Related Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2136100 - Disclosure - Pensions and Other Postretirement Benefits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/PensionsAndOtherPostretirementBenefits</Role>
      <ShortName>Pensions and Other Postretirement Benefits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2139100 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2140100 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2142100 - Disclosure - Restructuring and Other Initiatives</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/RestructuringAndOtherInitiatives</Role>
      <ShortName>Restructuring and Other Initiatives</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2143100 - Disclosure - Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/StockholdersEquity</Role>
      <ShortName>Stockholders' Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2144100 - Disclosure - Earnings Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EarningsPerShare</Role>
      <ShortName>Earnings Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2145100 - Disclosure - Segment Reporting</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/SegmentReporting</Role>
      <ShortName>Segment Reporting</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2201201 - Disclosure - Nature of Operations and Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/NatureOfOperationsAndBasisOfPresentationPolicies</Role>
      <ShortName>Nature of Operations and Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Marketable Securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/MarketableSecuritiesTables</Role>
      <ShortName>Marketable Securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/MarketableSecurities</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2308301 - Disclosure - GM Financial Receivables (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/GmFinancialReceivablesTables</Role>
      <ShortName>GM Financial Receivables (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/GmFinancialReceivables</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2310301 - Disclosure - Inventories (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/InventoriesTables</Role>
      <ShortName>Inventories (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/Inventories</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2315301 - Disclosure - Equipment on Operating Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EquipmentOnOperatingLeasesTables</Role>
      <ShortName>Equipment on Operating Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/EquipmentOnOperatingLeases</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2322301 - Disclosure - Equity In Net Assets of Nonconsolidated Affiliates (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EquityInNetAssetsOfNonconsolidatedAffiliatesTables</Role>
      <ShortName>Equity In Net Assets of Nonconsolidated Affiliates (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/EquityInNetAssetsOfNonconsolidatedAffiliates</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2327301 - Disclosure - Variable Interest Entities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/VariableInterestEntitiesTables</Role>
      <ShortName>Variable Interest Entities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/VariableInterestEntities</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2332301 - Disclosure - Automotive and GM Financial Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/AutomotiveAndGmFinancialDebtTables</Role>
      <ShortName>Automotive and GM Financial Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/AutomotiveAndGmFinancialDebt</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2333301 - Disclosure - Derivative Financial Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/DerivativeFinancialInstrumentsTables</Role>
      <ShortName>Derivative Financial Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/DerivativeFinancialInstruments</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2335301 - Disclosure - Product Warranty and Related Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/ProductWarrantyAndRelatedLiabilitiesTables</Role>
      <ShortName>Product Warranty and Related Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/ProductWarrantyAndRelatedLiabilities</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2336301 - Disclosure - Pensions and Other Postretirement Benefits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/PensionsAndOtherPostretirementBenefitsTables</Role>
      <ShortName>Pensions and Other Postretirement Benefits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/PensionsAndOtherPostretirementBenefits</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2342301 - Disclosure - Restructuring and Other Initiatives (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/RestructuringAndOtherInitiativesTables</Role>
      <ShortName>Restructuring and Other Initiatives (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/RestructuringAndOtherInitiatives</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2343301 - Disclosure - Stockholders' Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/StockholdersEquityTables</Role>
      <ShortName>Stockholders' Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/StockholdersEquity</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2344301 - Disclosure - Earnings Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EarningsPerShareTables</Role>
      <ShortName>Earnings Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/EarningsPerShare</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2345301 - Disclosure - Segment Reporting (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/SegmentReportingTables</Role>
      <ShortName>Segment Reporting (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.gm.com/role/SegmentReporting</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2401402 - Disclosure - Nature of Operations and Basis of Presentation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/NatureOfOperationsAndBasisOfPresentationDetails</Role>
      <ShortName>Nature of Operations and Basis of Presentation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/NatureOfOperationsAndBasisOfPresentationPolicies</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2405401 - Disclosure - Disposition of Business (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/DispositionOfBusinessDetails</Role>
      <ShortName>Disposition of Business (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/DispositionOfBusiness</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2406402 - Disclosure - Marketable Securities Fair Value of Cash Equivalents and Marketable Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/MarketableSecuritiesFairValueOfCashEquivalentsAndMarketableSecuritiesDetails</Role>
      <ShortName>Marketable Securities Fair Value of Cash Equivalents and Marketable Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2406403 - Disclosure - Marketable Securities Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/MarketableSecuritiesReconciliationOfCashCashEquivalentsAndRestrictedCashDetails</Role>
      <ShortName>Marketable Securities Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2408402 - Disclosure - GM Financial Receivables Summary of Finance Receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/GmFinancialReceivablesSummaryOfFinanceReceivablesDetails</Role>
      <ShortName>GM Financial Receivables Summary of Finance Receivables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2408403 - Disclosure - GM Financial Receivables Allowance for Loan Losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/GmFinancialReceivablesAllowanceForLoanLossesDetails</Role>
      <ShortName>GM Financial Receivables Allowance for Loan Losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2408404 - Disclosure - GM Financial Receivables Retail Finance Receivables Delinquencies and TDRs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/GmFinancialReceivablesRetailFinanceReceivablesDelinquenciesAndTdrsDetails</Role>
      <ShortName>GM Financial Receivables Retail Finance Receivables Delinquencies and TDRs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2408405 - Disclosure - GM Financial Receivables Commercial Finance Receivables Credit Quality Indicators (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/GmFinancialReceivablesCommercialFinanceReceivablesCreditQualityIndicatorsDetails</Role>
      <ShortName>GM Financial Receivables Commercial Finance Receivables Credit Quality Indicators (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2410402 - Disclosure - Inventories (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/InventoriesDetails</Role>
      <ShortName>Inventories (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/InventoriesTables</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2415402 - Disclosure - Equipment on Operating Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EquipmentOnOperatingLeasesDetails</Role>
      <ShortName>Equipment on Operating Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/EquipmentOnOperatingLeasesTables</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2422402 - Disclosure - Equity In Net Assets of Nonconsolidated Affiliates (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EquityInNetAssetsOfNonconsolidatedAffiliatesDetails</Role>
      <ShortName>Equity In Net Assets of Nonconsolidated Affiliates (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/EquityInNetAssetsOfNonconsolidatedAffiliatesTables</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2427402 - Disclosure - Variable Interest Entities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/VariableInterestEntitiesDetails</Role>
      <ShortName>Variable Interest Entities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/VariableInterestEntitiesTables</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2432402 - Disclosure - Automotive and GM Financial Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/AutomotiveAndGmFinancialDebtDetails</Role>
      <ShortName>Automotive and GM Financial Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/AutomotiveAndGmFinancialDebtTables</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2432403 - Disclosure - Automotive and GM Financial Debt Other Disclosures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/AutomotiveAndGmFinancialDebtOtherDisclosuresDetails</Role>
      <ShortName>Automotive and GM Financial Debt Other Disclosures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2433402 - Disclosure - Derivative Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/DerivativeFinancialInstrumentsDetails</Role>
      <ShortName>Derivative Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/DerivativeFinancialInstrumentsTables</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2435402 - Disclosure - Product Warranty and Related Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/ProductWarrantyAndRelatedLiabilitiesDetails</Role>
      <ShortName>Product Warranty and Related Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/ProductWarrantyAndRelatedLiabilitiesTables</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2436402 - Disclosure - Pensions and Other Postretirement Benefits Schedule of Net Benefit Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/PensionsAndOtherPostretirementBenefitsScheduleOfNetBenefitCostsDetails</Role>
      <ShortName>Pensions and Other Postretirement Benefits Schedule of Net Benefit Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2439401 - Disclosure - Commitments and Contingencies Litigation-Related Liability and Tax Administrative Matters (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CommitmentsAndContingenciesLitigationRelatedLiabilityAndTaxAdministrativeMattersDetails</Role>
      <ShortName>Commitments and Contingencies Litigation-Related Liability and Tax Administrative Matters (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2439402 - Disclosure - Commitments and Contingencies Other Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/CommitmentsAndContingenciesOtherContingenciesDetails</Role>
      <ShortName>Commitments and Contingencies Other Contingencies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2440401 - Disclosure - Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/IncomeTaxesDetails</Role>
      <ShortName>Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/IncomeTaxes</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2442402 - Disclosure - Restructuring and Other Initiatives (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/RestructuringAndOtherInitiativesDetails</Role>
      <ShortName>Restructuring and Other Initiatives (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/RestructuringAndOtherInitiativesTables</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2443402 - Disclosure - Stockholders' Equity Preferred and Common Stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/StockholdersEquityPreferredAndCommonStockDetails</Role>
      <ShortName>Stockholders' Equity Preferred and Common Stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2443403 - Disclosure - Stockholders' Equity Accumulated Other Comprehensive Loss (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/StockholdersEquityAccumulatedOtherComprehensiveLossDetails</Role>
      <ShortName>Stockholders' Equity Accumulated Other Comprehensive Loss (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2444402 - Disclosure - Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/EarningsPerShareDetails</Role>
      <ShortName>Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/EarningsPerShareTables</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="gm-20170331.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2445402 - Disclosure - Segment Reporting (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.gm.com/role/SegmentReportingDetails</Role>
      <ShortName>Segment Reporting (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.gm.com/role/SegmentReportingTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>gm-20170331.xml</File>
    <File>gm-20170331.xsd</File>
    <File>gm-20170331_cal.xml</File>
    <File>gm-20170331_def.xml</File>
    <File>gm-20170331_lab.xml</File>
    <File>gm-20170331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies/>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
