<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.22.2.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>594</ContextCount>
  <ElementCount>384</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>131</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>11</UnitCount>
  <MyReports>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>100000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>100010 - Statement - CONSOLIDATED BALANCE SHEETS (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDBALANCESHEETSUnaudited</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>100020 - Statement - CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDBALANCESHEETSUnauditedParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>100030 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDSTATEMENTSOFOPERATIONSUnaudited</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>100040 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOMELOSSUnaudited</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>100050 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN OWNERS' EQUITY AND SERIES A PREFERRED STOCK</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDSTATEMENTSOFCHANGESINOWNERSEQUITYANDSERIESAPREFERREDSTOCK</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CHANGES IN OWNERS' EQUITY AND SERIES A PREFERRED STOCK</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>100060 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN OWNERS' EQUITY AND SERIES A PREFERRED STOCK (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDSTATEMENTSOFCHANGESINOWNERSEQUITYANDSERIESAPREFERREDSTOCKParenthetical</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CHANGES IN OWNERS' EQUITY AND SERIES A PREFERRED STOCK (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>100070 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_StatementCONSOLIDATEDSTATEMENTSOFCASHFLOWSUnaudited</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>100080 - Disclosure - Organization and Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureOrganizationAndOperations</Role>
      <ShortName>Organization and Operations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>100090 - Disclosure - Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureBasisOfPresentation</Role>
      <ShortName>Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>100100 - Disclosure - Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSignificantAccountingPolicies</Role>
      <ShortName>Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>100110 - Disclosure - Joint Ventures, Divestitures and Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitions</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>100120 - Disclosure - Property, Plant and Equipment and Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentAndIntangibleAssets</Role>
      <ShortName>Property, Plant and Equipment and Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>100130 - Disclosure - Investments in Unconsolidated Affiliates</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureInvestmentsInUnconsolidatedAffiliates</Role>
      <ShortName>Investments in Unconsolidated Affiliates</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>100140 - Disclosure - Debt Obligations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligations</Role>
      <ShortName>Debt Obligations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>100150 - Disclosure - Other Long-term Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureOtherLongTermLiabilities</Role>
      <ShortName>Other Long-term Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>100160 - Disclosure - Preferred Stock</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePreferredStock</Role>
      <ShortName>Preferred Stock</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>100170 - Disclosure - Common Stock and Related Matters</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureCommonStockAndRelatedMatters</Role>
      <ShortName>Common Stock and Related Matters</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>100180 - Disclosure - Earnings per Common Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShare</Role>
      <ShortName>Earnings per Common Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>100190 - Disclosure - Derivative Instruments and Hedging Activities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivities</Role>
      <ShortName>Derivative Instruments and Hedging Activities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>100200 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureFairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>100210 - Disclosure - Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureContingencies</Role>
      <ShortName>Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>100220 - Disclosure - Revenue</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureRevenue</Role>
      <ShortName>Revenue</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>100230 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>100240 - Disclosure - Supplemental Cash Flow Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformation</Role>
      <ShortName>Supplemental Cash Flow Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>100250 - Disclosure - Segment Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformation</Role>
      <ShortName>Segment Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>100260 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSignificantAccountingPolicies</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>100270 - Disclosure - Joint Ventures, Divestitures and Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitionsTables</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitions</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>100280 - Disclosure - Property, Plant and Equipment and Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentAndIntangibleAssetsTables</Role>
      <ShortName>Property, Plant and Equipment and Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentAndIntangibleAssets</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>100290 - Disclosure - Investments in Unconsolidated Affiliates (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureInvestmentsInUnconsolidatedAffiliatesTables</Role>
      <ShortName>Investments in Unconsolidated Affiliates (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureInvestmentsInUnconsolidatedAffiliates</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>100300 - Disclosure - Debt Obligations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsTables</Role>
      <ShortName>Debt Obligations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligations</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>100310 - Disclosure - Other Long-term Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureOtherLongTermLiabilitiesTables</Role>
      <ShortName>Other Long-term Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureOtherLongTermLiabilities</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>100320 - Disclosure - Common Stock and Related Matters (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureCommonStockAndRelatedMattersTables</Role>
      <ShortName>Common Stock and Related Matters (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureCommonStockAndRelatedMatters</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>100330 - Disclosure - Earnings per Common Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShareTables</Role>
      <ShortName>Earnings per Common Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShare</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>100340 - Disclosure - Derivative Instruments and Hedging Activities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesTables</Role>
      <ShortName>Derivative Instruments and Hedging Activities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivities</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>100350 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureFairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureFairValueMeasurements</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>100360 - Disclosure - Revenue (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureRevenueTables</Role>
      <ShortName>Revenue (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureRevenue</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>100370 - Disclosure - Supplemental Cash Flow Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformationTables</Role>
      <ShortName>Supplemental Cash Flow Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformation</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>100380 - Disclosure - Segment Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformationTables</Role>
      <ShortName>Segment Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformation</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>100390 - Disclosure - Joint Ventures, Divestitures and Acquisitions - Additional Information Joint Ventures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitionsAdditionalInformationJointVenturesDetails</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions - Additional Information Joint Ventures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>100400 - Disclosure - Joint Ventures, Divestitures and Acquisitions - Additional Information Acquisitions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitionsAdditionalInformationAcquisitionsDetails</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions - Additional Information Acquisitions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>100410 - Disclosure - Joint Ventures, Divestitures and Acquisitions - Summary of Preliminary Fair Values Assigned to Assets Acquired and Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitionsSummaryOfPreliminaryFairValuesAssignedToAssetsAcquiredAndLiabilitiesAssumedDetails</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions - Summary of Preliminary Fair Values Assigned to Assets Acquired and Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>100420 - Disclosure - Joint Ventures, Divestitures and Acquisitions - Summary of Preliminary Fair Values Assigned to Assets Acquired and Liabilities Assumed (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/DisclosureJointVenturesDivestituresAndAcquisitionsSummaryOfPreliminaryFairValuesAssignedToAssetsAcquiredAndLiabilitiesAssumedParentheticalD</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions - Summary of Preliminary Fair Values Assigned to Assets Acquired and Liabilities Assumed (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>100430 - Disclosure - Joint Ventures, Divestitures and Acquisitions - Schedule of Unaudited Pro Forma Financial Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitionsScheduleOfUnauditedProFormaFinancialInformationDetails</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions - Schedule of Unaudited Pro Forma Financial Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>100440 - Disclosure - Joint Ventures, Divestitures and Acquisitions - Additional Information Divestitures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureJointVenturesDivestituresAndAcquisitionsAdditionalInformationDivestituresDetails</Role>
      <ShortName>Joint Ventures, Divestitures and Acquisitions - Additional Information Divestitures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>100450 - Disclosure - Property, Plant and Equipment and Intangible Assets - Property, Plant and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentAndIntangibleAssetsPropertyPlantAndEquipmentDetails</Role>
      <ShortName>Property, Plant and Equipment and Intangible Assets - Property, Plant and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>100460 - Disclosure - Property, Plant and Equipment and Intangible Assets - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentAndIntangibleAssetsAdditionalInformationDetails</Role>
      <ShortName>Property, Plant and Equipment and Intangible Assets - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>100470 - Disclosure - Property, Plant and Equipment and Intangible Assets - Schedule of Changes in Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentAndIntangibleAssetsScheduleOfChangesInIntangibleAssetsDetails</Role>
      <ShortName>Property, Plant and Equipment and Intangible Assets - Schedule of Changes in Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>100480 - Disclosure - Investments in Unconsolidated Affiliates - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureInvestmentsInUnconsolidatedAffiliatesAdditionalInformationDetails</Role>
      <ShortName>Investments in Unconsolidated Affiliates - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>100490 - Disclosure - Investments in Unconsolidated Affiliates - Activity Related to Partnership's Investments in Unconsolidated Affiliates (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureInvestmentsInUnconsolidatedAffiliatesActivityRelatedToPartnershipSInvestmentsInUnconsolidatedAffiliatesDetails</Role>
      <ShortName>Investments in Unconsolidated Affiliates - Activity Related to Partnership's Investments in Unconsolidated Affiliates (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>100500 - Disclosure - Investments in Unconsolidated Affiliates - Activity Related to Partnership's Investments in Unconsolidated Affiliates (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureInvestmentsInUnconsolidatedAffiliatesActivityRelatedToPartnershipSInvestmentsInUnconsolidatedAffiliatesParentheticalDetails</Role>
      <ShortName>Investments in Unconsolidated Affiliates - Activity Related to Partnership's Investments in Unconsolidated Affiliates (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>100510 - Disclosure - Debt Obligations - Summary Of Debt Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsSummaryOfDebtObligationsDetails</Role>
      <ShortName>Debt Obligations - Summary Of Debt Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>100520 - Disclosure - Debt Obligations - Summary Of Debt Obligations (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsSummaryOfDebtObligationsParentheticalDetails</Role>
      <ShortName>Debt Obligations - Summary Of Debt Obligations (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>100530 - Disclosure - Debt Obligations - Range of Interest Rates and Weighted Average Interest Rate Incurred on Variable Rate Debt Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsRangeOfInterestRatesAndWeightedAverageInterestRateIncurredOnVariableRateDebtObligationsDetails</Role>
      <ShortName>Debt Obligations - Range of Interest Rates and Weighted Average Interest Rate Incurred on Variable Rate Debt Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>100540 - Disclosure - Debt Obligations - Compliance with Debt Covenants - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsComplianceWithDebtCovenantsAdditionalInformationDetails</Role>
      <ShortName>Debt Obligations - Compliance with Debt Covenants - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>100550 - Disclosure - Debt Obligations - Partnership's Accounts Receivable Securitization Facility - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsPartnershipSAccountsReceivableSecuritizationFacilityAdditionalInformationDetails</Role>
      <ShortName>Debt Obligations - Partnership's Accounts Receivable Securitization Facility - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>100560 - Disclosure - Debt Obligations - TRGP Revolver - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsTRGPRevolverAdditionalInformationDetails</Role>
      <ShortName>Debt Obligations - TRGP Revolver - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>100570 - Disclosure - Debt Obligations - Term Loan Facility - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsTermLoanFacilityAdditionalInformationDetails</Role>
      <ShortName>Debt Obligations - Term Loan Facility - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>100580 - Disclosure - Debt Obligations - Commercial Paper Program - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsCommercialPaperProgramAdditionalInformationDetails</Role>
      <ShortName>Debt Obligations - Commercial Paper Program - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>100590 - Disclosure - Debt Obligations - Senior Unsecured Notes Redemptions and Issuance - Additional Information (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsSeniorUnsecuredNotesRedemptionsAndIssuanceAdditionalInformationDetails</Role>
      <ShortName>Debt Obligations - Senior Unsecured Notes Redemptions and Issuance - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>100600 - Disclosure - Debt Obligations - Summary of Payment Obligations for Debt Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDebtObligationsSummaryOfPaymentObligationsForDebtInstrumentsDetails</Role>
      <ShortName>Debt Obligations - Summary of Payment Obligations for Debt Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>100610 - Disclosure - Debt Obligations - Summary of Payment Obligations for Debt Instruments (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/DisclosureDebtObligationsSummaryOfPaymentObligationsForDebtInstrumentsParentheticalDetails</Role>
      <ShortName>Debt Obligations - Summary of Payment Obligations for Debt Instruments (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>100620 - Disclosure - Other Long-term Liabilities - Schedule of Other Long-term Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureOtherLongTermLiabilitiesScheduleOfOtherLongTermLiabilitiesDetails</Role>
      <ShortName>Other Long-term Liabilities - Schedule of Other Long-term Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>100630 - Disclosure - Other Long-term Liabilities - Deferred Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureOtherLongTermLiabilitiesDeferredRevenueDetails</Role>
      <ShortName>Other Long-term Liabilities - Deferred Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>100640 - Disclosure - Preferred Stock - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosurePreferredStockAdditionalInformationDetails</Role>
      <ShortName>Preferred Stock - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>100650 - Disclosure - Common Stock and Related Matters - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureCommonStockAndRelatedMattersAdditionalInformationDetails</Role>
      <ShortName>Common Stock and Related Matters - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>100660 - Disclosure - Common Stock and Related Matters - Dividends Declared And Or Paid (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureCommonStockAndRelatedMattersDividendsDeclaredAndOrPaidDetails</Role>
      <ShortName>Common Stock and Related Matters - Dividends Declared And Or Paid (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>100670 - Disclosure - Earnings per Common Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShareDetails</Role>
      <ShortName>Earnings per Common Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShareTables</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>100680 - Disclosure - Earnings per Common Share - Summary of Potential Common Stock Equivalents Excluded from Determination of Diluted Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShareSummaryOfPotentialCommonStockEquivalentsExcludedFromDeterminationOfDilutedEarningsPerShareDetails</Role>
      <ShortName>Earnings per Common Share - Summary of Potential Common Stock Equivalents Excluded from Determination of Diluted Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>100690 - Disclosure - Earnings per Common Share - Summary of Potential Common Stock Equivalents Excluded from Determination of Diluted Earnings Per Share (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureEarningsPerCommonShareSummaryOfPotentialCommonStockEquivalentsExcludedFromDeterminationOfDilutedEarningsPerShareParentheticalDetails</Role>
      <ShortName>Earnings per Common Share - Summary of Potential Common Stock Equivalents Excluded from Determination of Diluted Earnings Per Share (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>100700 - Disclosure - Derivative Instruments and Hedging Activities - Notional Volumes Of The Partnership's Commodity Derivative Contracts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesNotionalVolumesOfThePartnershipSCommodityDerivativeContractsDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities - Notional Volumes Of The Partnership's Commodity Derivative Contracts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>100710 - Disclosure - Derivative Instruments and Hedging Activities, Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesFairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities, Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>100720 - Disclosure - Derivative Instruments and Hedging Activities - Pro Forma Impact Of Offsetting Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesProFormaImpactOfOffsettingAssetsDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities - Pro Forma Impact Of Offsetting Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>100730 - Disclosure - Derivative Instruments and Hedging Activities - Pro Forma Impact Of Offsetting Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesProFormaImpactOfOffsettingLiabilitiesDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities - Pro Forma Impact Of Offsetting Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>100740 - Disclosure - Derivative Instruments and Hedging Activities, Pro Forma Impact - Offsetting Collateral (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesProFormaImpactOffsettingCollateralDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities, Pro Forma Impact - Offsetting Collateral (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>100750 - Disclosure - Derivative Instruments and Hedging Activities - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesAdditionalInformationDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>100760 - Disclosure - Derivative Instruments and Hedging Activities - Amounts Included in OCI, Income and AOCI (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureDerivativeInstrumentsAndHedgingActivitiesAmountsIncludedInOCIIncomeAndAOCIDetails</Role>
      <ShortName>Derivative Instruments and Hedging Activities - Amounts Included in OCI, Income and AOCI (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>100770 - Disclosure - Fair Value Measurements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetails</Role>
      <ShortName>Fair Value Measurements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>100780 - Disclosure - Fair Value Measurements - Breakdown by Fair Value Hierarchy Category for Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureFairValueMeasurementsBreakdownByFairValueHierarchyCategoryForFinancialInstrumentsDetails</Role>
      <ShortName>Fair Value Measurements - Breakdown by Fair Value Hierarchy Category for Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>100790 - Disclosure - Contingencies - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureContingenciesAdditionalInformationDetails</Role>
      <ShortName>Contingencies - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>100800 - Disclosure - Revenue - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureRevenueAdditionalInformationDetails</Role>
      <ShortName>Revenue - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>100810 - Disclosure - Revenue - Estimated Minimum Revenue Expected to be Recognized in Future Related to Unsatisfied Performance Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureRevenueEstimatedMinimumRevenueExpectedToBeRecognizedInFutureRelatedToUnsatisfiedPerformanceObligationsDetails</Role>
      <ShortName>Revenue - Estimated Minimum Revenue Expected to be Recognized in Future Related to Unsatisfied Performance Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>100820 - Disclosure - Income Taxes - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetails</Role>
      <ShortName>Income Taxes - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>100830 - Disclosure - Supplemental Cash Flow Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformationDetails</Role>
      <ShortName>Supplemental Cash Flow Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformationTables</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>100840 - Disclosure - Supplemental Cash Flow Information (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformationParentheticalDetails</Role>
      <ShortName>Supplemental Cash Flow Information (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSupplementalCashFlowInformationTables</ParentRole>
      <Position>85</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>100850 - Disclosure - Segment Information - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformationAdditionalInformationDetails</Role>
      <ShortName>Segment Information - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>100860 - Disclosure - Segment Information - Revenues and Operating Margin (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformationRevenuesAndOperatingMarginDetails</Role>
      <ShortName>Segment Information - Revenues and Operating Margin (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>100870 - Disclosure - Segment Information - Other Financial Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformationOtherFinancialInformationDetails</Role>
      <ShortName>Segment Information - Other Financial Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>100880 - Disclosure - Segment Information - Summary of Consolidated Revenues Disaggregated by Product and Service (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformationSummaryOfConsolidatedRevenuesDisaggregatedByProductAndServiceDetails</Role>
      <ShortName>Segment Information - Summary of Consolidated Revenues Disaggregated by Product and Service (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="trgp-20220930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>100890 - Disclosure - Segment Information - Reconciliation of Reportable Segment Operating Margin to Income (Loss) Before Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.targaresources.com/20220930/taxonomy/role/Role_DisclosureSegmentInformationReconciliationOfReportableSegmentOperatingMarginToIncomeLossBeforeIncomeTaxesDetails</Role>
      <ShortName>Segment Information - Reconciliation of Reportable Segment Operating Margin to Income (Loss) Before Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Warning">[ix-0514-Hidden-Fact-Eligible-For-Transform] WARN: 37 fact(s) appearing in ix:hidden were eligible for transformation: us-gaap:CommitmentsAndContingencies, us-gaap:DebtInstrumentMaturityDate, us-gaap:PropertyPlantAndEquipmentEstimatedUsefulLives, us-gaap:RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1 -  trgp-20220930.htm 8</Log>
  </Logs>
  <InputFiles>
    <File doctype="10-Q" original="trgp-20220930.htm">trgp-20220930.htm</File>
    <File>trgp-20220930.xsd</File>
    <File>trgp-20220930_cal.xml</File>
    <File>trgp-20220930_def.xml</File>
    <File>trgp-20220930_lab.xml</File>
    <File>trgp-20220930_pre.xml</File>
    <File>trgp-ex10_1.htm</File>
    <File>trgp-ex10_2.htm</File>
    <File>trgp-ex10_3.htm</File>
    <File>trgp-ex10_4.htm</File>
    <File>trgp-ex10_5.htm</File>
    <File>trgp-ex10_6.htm</File>
    <File>trgp-ex22_1.htm</File>
    <File>trgp-ex31_1.htm</File>
    <File>trgp-ex31_2.htm</File>
    <File>trgp-ex32_1.htm</File>
    <File>trgp-ex32_2.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>img100071242_0.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="1">http://fasb.org/srt/2022</BaseTaxonomy>
    <BaseTaxonomy items="1379">http://fasb.org/us-gaap/2022</BaseTaxonomy>
    <BaseTaxonomy items="30">http://xbrl.sec.gov/dei/2022</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
