<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.24.3</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>570</ContextCount>
  <ElementCount>456</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>143</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>19</UnitCount>
  <MyReports>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - Condensed Statements of Consolidated Income (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedIncomeUnaudited</Role>
      <ShortName>Condensed Statements of Consolidated Income (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - Condensed Statements of Consolidated Comprehensive Income (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedComprehensiveIncomeUnaudited</Role>
      <ShortName>Condensed Statements of Consolidated Comprehensive Income (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - Condensed Statements of Consolidated Comprehensive Income (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedComprehensiveIncomeUnauditedParenthetical</Role>
      <ShortName>Condensed Statements of Consolidated Comprehensive Income (Unaudited) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - Condensed Consolidated Balance Sheets (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedConsolidatedBalanceSheetsUnaudited</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedConsolidatedBalanceSheetsUnauditedParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Statement - Condensed Statements of Consolidated Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedCashFlowsUnaudited</Role>
      <ShortName>Condensed Statements of Consolidated Cash Flows (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Statement - Condensed Statements of Consolidated Changes in Equity (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedChangesinEquityUnaudited</Role>
      <ShortName>Condensed Statements of Consolidated Changes in Equity (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Statement - Condensed Statements of Consolidated Changes in Equity (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedChangesinEquityUnauditedParenthetical</Role>
      <ShortName>Condensed Statements of Consolidated Changes in Equity (Unaudited) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Statement - Condensed Statements of Consolidated Income (Unaudited) - Houston Electric</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedIncomeUnauditedHoustonElectric</Role>
      <ShortName>Condensed Statements of Consolidated Income (Unaudited) - Houston Electric</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Statement - Condensed Consolidated Balance Sheets (Unaudited) - Houston Electric</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedConsolidatedBalanceSheetsUnauditedHoustonElectric</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) - Houston Electric</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Statement - Condensed Consolidated Balance Sheets (Unaudited) - Houston Electric (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedConsolidatedBalanceSheetsUnauditedHoustonElectricParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) - Houston Electric (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Statement - Condensed Statements of Consolidated Cash Flows (Unaudited) - Houston Electric</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedCashFlowsUnauditedHoustonElectric</Role>
      <ShortName>Condensed Statements of Consolidated Cash Flows (Unaudited) - Houston Electric</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Statement - Condensed Statements of Consolidated Changes in Equity (Unaudited) - Houston Electric</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedChangesinEquityUnauditedHoustonElectric</Role>
      <ShortName>Condensed Statements of Consolidated Changes in Equity (Unaudited) - Houston Electric</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952164 - Statement - Condensed Statements of Consolidated Income (Unaudited) - CERC</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedIncomeUnauditedCERC</Role>
      <ShortName>Condensed Statements of Consolidated Income (Unaudited) - CERC</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952165 - Statement - Condensed Statements of Consolidated Comprehensive Income (Unaudited) - CERC</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedComprehensiveIncomeUnauditedCERC</Role>
      <ShortName>Condensed Statements of Consolidated Comprehensive Income (Unaudited) - CERC</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952166 - Statement - Condensed Statements of Consolidated Comprehensive Income (Unaudited) - CERC (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedComprehensiveIncomeUnauditedCERCParenthetical</Role>
      <ShortName>Condensed Statements of Consolidated Comprehensive Income (Unaudited) - CERC (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952167 - Statement - Condensed Consolidated Balance Sheets (Unaudited) - CERC</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedConsolidatedBalanceSheetsUnauditedCERC</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) - CERC</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952168 - Statement - Condensed Consolidated Balance Sheets (Unaudited) - CERC (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedConsolidatedBalanceSheetsUnauditedCERCParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) - CERC (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952169 - Statement - Condensed Statements of Consolidated Cash Flows (Unaudited) - CERC</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedCashFlowsUnauditedCERC</Role>
      <ShortName>Condensed Statements of Consolidated Cash Flows (Unaudited) - CERC</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952170 - Statement - Condensed Statements of Consolidated Changes in Equity (Unaudited) - CERC</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CondensedStatementsofConsolidatedChangesinEquityUnauditedCERC</Role>
      <ShortName>Condensed Statements of Consolidated Changes in Equity (Unaudited) - CERC</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - Background and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/BackgroundandBasisofPresentation</Role>
      <ShortName>Background and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - New Accounting Pronouncements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/NewAccountingPronouncements</Role>
      <ShortName>New Accounting Pronouncements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - Held for Sale and Divestitures (CenterPoint Energy and CERC)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERC</Role>
      <ShortName>Held for Sale and Divestitures (CenterPoint Energy and CERC)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - Revenue Recognition and Allowance for Credit Losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RevenueRecognitionandAllowanceforCreditLosses</Role>
      <ShortName>Revenue Recognition and Allowance for Credit Losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - Employee Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EmployeeBenefitPlans</Role>
      <ShortName>Employee Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - Regulatory Matters</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RegulatoryMatters</Role>
      <ShortName>Regulatory Matters</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9952177 - Disclosure - Derivative Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/DerivativeInstruments</Role>
      <ShortName>Derivative Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9952178 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9952179 - Disclosure - Goodwill (CenterPoint Energy and CERC)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/GoodwillCenterPointEnergyandCERC</Role>
      <ShortName>Goodwill (CenterPoint Energy and CERC)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9952180 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergy</Role>
      <ShortName>Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9952181 - Disclosure - Short-term Borrowings and Long-term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebt</Role>
      <ShortName>Short-term Borrowings and Long-term Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9952182 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9952183 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9952184 - Disclosure - Earnings Per Share (CenterPoint Energy)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergy</Role>
      <ShortName>Earnings Per Share (CenterPoint Energy)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9952185 - Disclosure - Reportable Segments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ReportableSegments</Role>
      <ShortName>Reportable Segments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9952186 - Disclosure - Supplemental Disclosure of Cash Flow and Balance Sheet Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformation</Role>
      <ShortName>Supplemental Disclosure of Cash Flow and Balance Sheet Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9952187 - Disclosure - Related Party Transactions (Houston Electric and CERC)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERC</Role>
      <ShortName>Related Party Transactions (Houston Electric and CERC)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9952188 - Disclosure - Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/Equity</Role>
      <ShortName>Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9952189 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/Leases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>995410 - Disclosure - Pay vs Performance Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/PvpDisclosure</Role>
      <ShortName>Pay vs Performance Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9954471 - Disclosure - Background and Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/BackgroundandBasisofPresentationPolicies</Role>
      <ShortName>Background and Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/NewAccountingPronouncements</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9954472 - Disclosure - Held for Sale and Divestitures (CenterPoint Energy and CERC) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCTables</Role>
      <ShortName>Held for Sale and Divestitures (CenterPoint Energy and CERC) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERC</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9954473 - Disclosure - Revenue Recognition and Allowance for Credit Losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RevenueRecognitionandAllowanceforCreditLossesTables</Role>
      <ShortName>Revenue Recognition and Allowance for Credit Losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/RevenueRecognitionandAllowanceforCreditLosses</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9954474 - Disclosure - Employee Benefit Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EmployeeBenefitPlansTables</Role>
      <ShortName>Employee Benefit Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EmployeeBenefitPlans</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9954475 - Disclosure - Regulatory Matters (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RegulatoryMattersTables</Role>
      <ShortName>Regulatory Matters (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/RegulatoryMatters</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9954476 - Disclosure - Derivative Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/DerivativeInstrumentsTables</Role>
      <ShortName>Derivative Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/DerivativeInstruments</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9954477 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/FairValueMeasurements</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9954478 - Disclosure - Goodwill (CenterPoint Energy and CERC) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/GoodwillCenterPointEnergyandCERCTables</Role>
      <ShortName>Goodwill (CenterPoint Energy and CERC) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/GoodwillCenterPointEnergyandCERC</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9954479 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables</Role>
      <ShortName>Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergy</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9954480 - Disclosure - Short-term Borrowings and Long-term Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtTables</Role>
      <ShortName>Short-term Borrowings and Long-term Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebt</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9954481 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/IncomeTaxes</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9954482 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/CommitmentsandContingencies</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9954483 - Disclosure - Earnings Per Share (CenterPoint Energy) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergyTables</Role>
      <ShortName>Earnings Per Share (CenterPoint Energy) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergy</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9954484 - Disclosure - Reportable Segments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ReportableSegmentsTables</Role>
      <ShortName>Reportable Segments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/ReportableSegments</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9954485 - Disclosure - Supplemental Disclosure of Cash Flow and Balance Sheet Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformationTables</Role>
      <ShortName>Supplemental Disclosure of Cash Flow and Balance Sheet Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformation</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9954486 - Disclosure - Related Party Transactions (Houston Electric and CERC) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables</Role>
      <ShortName>Related Party Transactions (Houston Electric and CERC) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERC</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9954487 - Disclosure - Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquityTables</Role>
      <ShortName>Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergy</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9954488 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/LeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/Leases</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9954489 - Disclosure - Background and Basis of Presentation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/BackgroundandBasisofPresentationDetails</Role>
      <ShortName>Background and Basis of Presentation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/BackgroundandBasisofPresentationPolicies</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9954490 - Disclosure - Held for Sale and Divestitures (CenterPoint Energy and CERC) - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCNarrativeDetails</Role>
      <ShortName>Held for Sale and Divestitures (CenterPoint Energy and CERC) - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCTables</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9954491 - Disclosure - Held for Sale and Divestitures (CenterPoint Energy and CERC) - Asset and Liabilities Held for Sale (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCAssetandLiabilitiesHeldforSaleDetails</Role>
      <ShortName>Held for Sale and Divestitures (CenterPoint Energy and CERC) - Asset and Liabilities Held for Sale (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCTables</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9954492 - Disclosure - Held for Sale and Divestitures (CenterPoint Energy and CERC) - Pre Tax Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCPreTaxIncomeDetails</Role>
      <ShortName>Held for Sale and Divestitures (CenterPoint Energy and CERC) - Pre Tax Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/HeldforSaleandDivestituresCenterPointEnergyandCERCTables</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9954493 - Disclosure - Revenue Recognition and Allowance for Credit Losses - Disaggregation of Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RevenueRecognitionandAllowanceforCreditLossesDisaggregationofRevenueDetails</Role>
      <ShortName>Revenue Recognition and Allowance for Credit Losses - Disaggregation of Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9954494 - Disclosure - Revenue Recognition and Allowance for Credit Losses - Schedule of Contract Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RevenueRecognitionandAllowanceforCreditLossesScheduleofContractAssetsandLiabilitiesDetails</Role>
      <ShortName>Revenue Recognition and Allowance for Credit Losses - Schedule of Contract Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9954495 - Disclosure - Employee Benefit Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EmployeeBenefitPlansDetails</Role>
      <ShortName>Employee Benefit Plans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EmployeeBenefitPlansTables</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9954496 - Disclosure - Regulatory Matters - Schedule of Allowed Equity Return Recognized (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RegulatoryMattersScheduleofAllowedEquityReturnRecognizedDetails</Role>
      <ShortName>Regulatory Matters - Schedule of Allowed Equity Return Recognized (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9954497 - Disclosure - Regulatory Matters - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RegulatoryMattersNarrativeDetails</Role>
      <ShortName>Regulatory Matters - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9954498 - Disclosure - Derivative Instruments - Interest Rate Hedging and Weather Hedges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/DerivativeInstrumentsInterestRateHedgingandWeatherHedgesDetails</Role>
      <ShortName>Derivative Instruments - Interest Rate Hedging and Weather Hedges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>9954499 - Disclosure - Derivative Instruments - Schedule of Derivative Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/DerivativeInstrumentsScheduleofDerivativeActivityDetails</Role>
      <ShortName>Derivative Instruments - Schedule of Derivative Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>9954500 - Disclosure - Derivative Instruments - Gross Indexed Securities and Credit Risk Contingent Features (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/DerivativeInstrumentsGrossIndexedSecuritiesandCreditRiskContingentFeaturesDetails</Role>
      <ShortName>Derivative Instruments - Gross Indexed Securities and Credit Risk Contingent Features (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>9954501 - Disclosure - Fair Value Measurements - Schedule of Assets and Liabilities Measured On Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/FairValueMeasurementsScheduleofAssetsandLiabilitiesMeasuredOnRecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements - Schedule of Assets and Liabilities Measured On Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>9954502 - Disclosure - Fair Value Measurements - Schedule of Estimated Fair Value of Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/FairValueMeasurementsScheduleofEstimatedFairValueofFinancialInstrumentsDetails</Role>
      <ShortName>Fair Value Measurements - Schedule of Estimated Fair Value of Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>9954503 - Disclosure - Goodwill (CenterPoint Energy and CERC) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/GoodwillCenterPointEnergyandCERCDetails</Role>
      <ShortName>Goodwill (CenterPoint Energy and CERC) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/GoodwillCenterPointEnergyandCERCTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>9954504 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Gain (Loss) On Equity Securities (CenterPoint Energy) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyScheduleofGainLossOnEquitySecuritiesCenterPointEnergyDetails</Role>
      <ShortName>Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Gain (Loss) On Equity Securities (CenterPoint Energy) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>9954505 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Securities Classified as Trading (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyScheduleofSecuritiesClassifiedasTradingDetails</Role>
      <ShortName>Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Securities Classified as Trading (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>9954506 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyNarrativeDetails</Role>
      <ShortName>Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>9954507 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Reference Shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyScheduleofReferenceSharesDetails</Role>
      <ShortName>Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Reference Shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables</ParentRole>
      <Position>79</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>9954508 - Disclosure - Short-term Borrowings and Long-term Debt - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtNarrativeDetails</Role>
      <ShortName>Short-term Borrowings and Long-term Debt - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>9954509 - Disclosure - Short-term Borrowings and Long-term Debt - Schedule of Revolving Credit Facilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtScheduleofRevolvingCreditFacilitiesDetails</Role>
      <ShortName>Short-term Borrowings and Long-term Debt - Schedule of Revolving Credit Facilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>9954510 - Disclosure - Short-term Borrowings and Long-term Debt - Schedule of Utilization of Credit Facilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtScheduleofUtilizationofCreditFacilitiesDetails</Role>
      <ShortName>Short-term Borrowings and Long-term Debt - Schedule of Utilization of Credit Facilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>9954511 - Disclosure - Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/IncomeTaxesDetails</Role>
      <ShortName>Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/IncomeTaxesTables</ParentRole>
      <Position>83</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>9954512 - Disclosure - Commitments and Contingencies - Purchase Commitments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingenciesPurchaseCommitmentsDetails</Role>
      <ShortName>Commitments and Contingencies - Purchase Commitments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>9954513 - Disclosure - Commitments and Contingencies - Schedule of Undiscounted Minimum Purchase Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingenciesScheduleofUndiscountedMinimumPurchaseObligationsDetails</Role>
      <ShortName>Commitments and Contingencies - Schedule of Undiscounted Minimum Purchase Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>9954514 - Disclosure - Commitments and Contingencies - Guarantees and Product Warranties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingenciesGuaranteesandProductWarrantiesDetails</Role>
      <ShortName>Commitments and Contingencies - Guarantees and Product Warranties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>9954515 - Disclosure - Commitments and Contingencies - Legal, Environmental and Other Matters (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingenciesLegalEnvironmentalandOtherMattersDetails</Role>
      <ShortName>Commitments and Contingencies - Legal, Environmental and Other Matters (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>9954516 - Disclosure - Commitments and Contingencies - Schedule of Estimated Accrued Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/CommitmentsandContingenciesScheduleofEstimatedAccruedCostsDetails</Role>
      <ShortName>Commitments and Contingencies - Schedule of Estimated Accrued Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>9954517 - Disclosure - Earnings Per Share (CenterPoint Energy) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergyDetails</Role>
      <ShortName>Earnings Per Share (CenterPoint Energy) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergyTables</ParentRole>
      <Position>89</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>9954518 - Disclosure - Reportable Segments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/ReportableSegmentsDetails</Role>
      <ShortName>Reportable Segments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/ReportableSegmentsTables</ParentRole>
      <Position>90</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>9954519 - Disclosure - Supplemental Disclosure of Cash Flow and Balance Sheet Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformationDetails</Role>
      <ShortName>Supplemental Disclosure of Cash Flow and Balance Sheet Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformationTables</ParentRole>
      <Position>91</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>9954520 - Disclosure - Related Party Transactions (Houston Electric and CERC) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCDetails</Role>
      <ShortName>Related Party Transactions (Houston Electric and CERC) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables</ParentRole>
      <Position>92</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>9954521 - Disclosure - Equity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquityDetails</Role>
      <ShortName>Equity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables</ParentRole>
      <Position>93</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>9954522 - Disclosure - Equity - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/EquityNarrativeDetails</Role>
      <ShortName>Equity - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="cnp-20240930.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>9954523 - Disclosure - Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.centerpointenergy.com/role/LeasesDetails</Role>
      <ShortName>Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.centerpointenergy.com/role/LeasesTables</ParentRole>
      <Position>95</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-Q" isDefinitelyFs="true" isUsgaap="true" original="cnp-20240930.htm">cnp-20240930.htm</File>
    <File>cnp-20240930.xsd</File>
    <File>cnp-20240930_cal.xml</File>
    <File>cnp-20240930_def.xml</File>
    <File>cnp-20240930_lab.xml</File>
    <File>cnp-20240930_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="1982">http://fasb.org/us-gaap/2024</BaseTaxonomy>
    <BaseTaxonomy items="74">http://xbrl.sec.gov/dei/2024</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2024</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
