3.24.0.1 html 1259 727 1 false 294 0 false 24 false false R1.htm 0000001 - Document - Cover Page Sheet http://www.centerpointenergy.com/role/CoverPage Cover Page Cover 1 false false R2.htm 0000002 - Document - Audit Information Sheet http://www.centerpointenergy.com/role/AuditInformation Audit Information Cover 2 false false R3.htm 0000003 - Statement - STATEMENTS OF CONSOLIDATED INCOME Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDINCOME STATEMENTS OF CONSOLIDATED INCOME Statements 3 false false R4.htm 0000004 - Statement - STATEMENTS OF CONSOLIDATED INCOME (Parenthetical) Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDINCOMEParenthetical STATEMENTS OF CONSOLIDATED INCOME (Parenthetical) Statements 4 false false R5.htm 0000005 - Statement - STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCOMPREHENSIVEINCOME STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME Statements 5 false false R6.htm 0000006 - Statement - STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Parenthetical) Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCOMPREHENSIVEINCOMEParenthetical STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Parenthetical) Statements 6 false false R7.htm 0000007 - Statement - CONSOLIDATED BALANCE SHEETS Sheet http://www.centerpointenergy.com/role/CONSOLIDATEDBALANCESHEETS CONSOLIDATED BALANCE SHEETS Statements 7 false false R8.htm 0000008 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) Sheet http://www.centerpointenergy.com/role/CONSOLIDATEDBALANCESHEETSParenthetical CONSOLIDATED BALANCE SHEETS (Parenthetical) Statements 8 false false R9.htm 0000009 - Statement - STATEMENTS OF CONSOLIDATED CASH FLOWS Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCASHFLOWS STATEMENTS OF CONSOLIDATED CASH FLOWS Statements 9 false false R10.htm 0000010 - Statement - STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCHANGESINEQUITY STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY Statements 10 false false R11.htm 0000011 - Statement - STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY (Parenthetical) Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCHANGESINEQUITYParenthetical STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY (Parenthetical) Statements 11 false false R12.htm 0000012 - Statement - STATEMENTS OF CONSOLIDATED INCOME - HOUSTON ELECTRIC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDINCOMEHOUSTONELECTRIC STATEMENTS OF CONSOLIDATED INCOME - HOUSTON ELECTRIC Statements 12 false false R13.htm 0000013 - Statement - CONSOLIDATED BALANCE SHEETS - HOUSTON ELECTRIC Sheet http://www.centerpointenergy.com/role/CONSOLIDATEDBALANCESHEETSHOUSTONELECTRIC CONSOLIDATED BALANCE SHEETS - HOUSTON ELECTRIC Statements 13 false false R14.htm 0000014 - Statement - CONSOLIDATED BALANCE SHEETS - HOUSTON ELECTRIC (Parenthetical) Sheet http://www.centerpointenergy.com/role/CONSOLIDATEDBALANCESHEETSHOUSTONELECTRICParenthetical CONSOLIDATED BALANCE SHEETS - HOUSTON ELECTRIC (Parenthetical) Statements 14 false false R15.htm 0000015 - Statement - STATEMENTS OF CONSOLIDATED CASH FLOWS - HOUSTON ELECTRIC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCASHFLOWSHOUSTONELECTRIC STATEMENTS OF CONSOLIDATED CASH FLOWS - HOUSTON ELECTRIC Statements 15 false false R16.htm 0000016 - Statement - STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY - HOUSTON ELECTRIC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCHANGESINEQUITYHOUSTONELECTRIC STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY - HOUSTON ELECTRIC Statements 16 false false R17.htm 0000017 - Statement - STATEMENTS OF CONSOLIDATED INCOME - CERC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDINCOMECERC STATEMENTS OF CONSOLIDATED INCOME - CERC Statements 17 false false R18.htm 0000018 - Statement - STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME - CERC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCOMPREHENSIVEINCOMECERC STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME - CERC Statements 18 false false R19.htm 0000019 - Statement - STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME - CERC (Parenthetical) Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCOMPREHENSIVEINCOMECERCParenthetical STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME - CERC (Parenthetical) Statements 19 false false R20.htm 0000020 - Statement - CONSOLIDATED BALANCE SHEETS - CERC Sheet http://www.centerpointenergy.com/role/CONSOLIDATEDBALANCESHEETSCERC CONSOLIDATED BALANCE SHEETS - CERC Statements 20 false false R21.htm 0000021 - Statement - CONSOLIDATED BALANCE SHEETS - CERC (Parenthetical) Sheet http://www.centerpointenergy.com/role/CONSOLIDATEDBALANCESHEETSCERCParenthetical CONSOLIDATED BALANCE SHEETS - CERC (Parenthetical) Statements 21 false false R22.htm 0000022 - Statement - STATEMENTS OF CONSOLIDATED CASH FLOWS - CERC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCASHFLOWSCERC STATEMENTS OF CONSOLIDATED CASH FLOWS - CERC Statements 22 false false R23.htm 0000023 - Statement - STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY - CERC Sheet http://www.centerpointenergy.com/role/STATEMENTSOFCONSOLIDATEDCHANGESINEQUITYCERC STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY - CERC Statements 23 false false R24.htm 0000024 - Disclosure - Background Sheet http://www.centerpointenergy.com/role/Background Background Notes 24 false false R25.htm 0000025 - Disclosure - Summary of Significant Accounting Policies Sheet http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 25 false false R26.htm 0000026 - Disclosure - Property, Plant and Equipment Sheet http://www.centerpointenergy.com/role/PropertyPlantandEquipment Property, Plant and Equipment Notes 26 false false R27.htm 0000027 - Disclosure - Divestitures (CenterPoint Energy and CERC) Sheet http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERC Divestitures (CenterPoint Energy and CERC) Notes 27 false false R28.htm 0000028 - Disclosure - Revenue Recognition Sheet http://www.centerpointenergy.com/role/RevenueRecognition Revenue Recognition Notes 28 false false R29.htm 0000029 - Disclosure - Goodwill and Other Intangibles (CenterPoint Energy and CERC) Sheet http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERC Goodwill and Other Intangibles (CenterPoint Energy and CERC) Notes 29 false false R30.htm 0000030 - Disclosure - Regulatory Matters Sheet http://www.centerpointenergy.com/role/RegulatoryMatters Regulatory Matters Notes 30 false false R31.htm 0000031 - Disclosure - Stock-Based Incentive Compensation Plans and Employee Benefit Plans Sheet http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlans Stock-Based Incentive Compensation Plans and Employee Benefit Plans Notes 31 false false R32.htm 0000032 - Disclosure - Derivative Instruments Sheet http://www.centerpointenergy.com/role/DerivativeInstruments Derivative Instruments Notes 32 false false R33.htm 0000033 - Disclosure - Fair Value Measurements Sheet http://www.centerpointenergy.com/role/FairValueMeasurements Fair Value Measurements Notes 33 false false R34.htm 0000034 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergy Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) Notes 34 false false R35.htm 0000035 - Disclosure - Equity (CenterPoint Energy) Sheet http://www.centerpointenergy.com/role/EquityCenterPointEnergy Equity (CenterPoint Energy) Notes 35 false false R36.htm 0000036 - Disclosure - Short-term Borrowings and Long-term Debt Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebt Short-term Borrowings and Long-term Debt Notes 36 false false R37.htm 0000037 - Disclosure - Income Taxes Sheet http://www.centerpointenergy.com/role/IncomeTaxes Income Taxes Notes 37 false false R38.htm 0000038 - Disclosure - Commitments and Contingencies Sheet http://www.centerpointenergy.com/role/CommitmentsandContingencies Commitments and Contingencies Notes 38 false false R39.htm 0000039 - Disclosure - Earnings Per Share (CenterPoint Energy) Sheet http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergy Earnings Per Share (CenterPoint Energy) Notes 39 false false R40.htm 0000040 - Disclosure - Reportable Segments Sheet http://www.centerpointenergy.com/role/ReportableSegments Reportable Segments Notes 40 false false R41.htm 0000041 - Disclosure - Supplemental Disclosure of Cash Flow and Balance Sheet Information Sheet http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformation Supplemental Disclosure of Cash Flow and Balance Sheet Information Notes 41 false false R42.htm 0000042 - Disclosure - Related Party Transactions (Houston Electric and CERC) Sheet http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERC Related Party Transactions (Houston Electric and CERC) Notes 42 false false R43.htm 0000043 - Disclosure - Leases Sheet http://www.centerpointenergy.com/role/Leases Leases Notes 43 false false R44.htm 0000044 - Disclosure - Subsequent Events Sheet http://www.centerpointenergy.com/role/SubsequentEvents Subsequent Events Notes 44 false false R45.htm 995410 - Disclosure - Pay vs Performance Disclosure Sheet http://xbrl.sec.gov/ecd/role/PvpDisclosure Pay vs Performance Disclosure Notes 45 false false R46.htm 995445 - Disclosure - Insider Trading Arrangements Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements Insider Trading Arrangements Notes 46 false false R47.htm 9954471 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPolicies 47 false false R48.htm 9954472 - Disclosure - Summary of Significant Accounting Policies (Tables) Sheet http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPoliciesTables Summary of Significant Accounting Policies (Tables) Tables http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPolicies 48 false false R49.htm 9954473 - Disclosure - Property, Plant and Equipment (Tables) Sheet http://www.centerpointenergy.com/role/PropertyPlantandEquipmentTables Property, Plant and Equipment (Tables) Tables http://www.centerpointenergy.com/role/PropertyPlantandEquipment 49 false false R50.htm 9954474 - Disclosure - Divestitures (CenterPoint Energy and CERC) (Tables) Sheet http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCTables Divestitures (CenterPoint Energy and CERC) (Tables) Tables http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERC 50 false false R51.htm 9954475 - Disclosure - Revenue Recognition (Tables) Sheet http://www.centerpointenergy.com/role/RevenueRecognitionTables Revenue Recognition (Tables) Tables http://www.centerpointenergy.com/role/RevenueRecognition 51 false false R52.htm 9954476 - Disclosure - Goodwill and Other Intangibles (CenterPoint Energy and CERC) (Tables) Sheet http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERCTables Goodwill and Other Intangibles (CenterPoint Energy and CERC) (Tables) Tables http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERC 52 false false R53.htm 9954477 - Disclosure - Regulatory Matters (Tables) Sheet http://www.centerpointenergy.com/role/RegulatoryMattersTables Regulatory Matters (Tables) Tables http://www.centerpointenergy.com/role/RegulatoryMatters 53 false false R54.htm 9954478 - Disclosure - Stock-Based Incentive Compensation Plans and Employee Benefit Plans (Tables) Sheet http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlansTables Stock-Based Incentive Compensation Plans and Employee Benefit Plans (Tables) Tables http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlans 54 false false R55.htm 9954479 - Disclosure - Derivative Instruments (Tables) Sheet http://www.centerpointenergy.com/role/DerivativeInstrumentsTables Derivative Instruments (Tables) Tables http://www.centerpointenergy.com/role/DerivativeInstruments 55 false false R56.htm 9954480 - Disclosure - Fair Value Measurements (Tables) Sheet http://www.centerpointenergy.com/role/FairValueMeasurementsTables Fair Value Measurements (Tables) Tables http://www.centerpointenergy.com/role/FairValueMeasurements 56 false false R57.htm 9954481 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) (Tables) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) (Tables) Tables http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergy 57 false false R58.htm 9954482 - Disclosure - Equity (CenterPoint Energy) (Tables) Sheet http://www.centerpointenergy.com/role/EquityCenterPointEnergyTables Equity (CenterPoint Energy) (Tables) Tables http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergy 58 false false R59.htm 9954483 - Disclosure - Short-term Borrowings and Long-term Debt (Tables) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtTables Short-term Borrowings and Long-term Debt (Tables) Tables http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebt 59 false false R60.htm 9954484 - Disclosure - Income Taxes (Tables) Sheet http://www.centerpointenergy.com/role/IncomeTaxesTables Income Taxes (Tables) Tables http://www.centerpointenergy.com/role/IncomeTaxes 60 false false R61.htm 9954485 - Disclosure - Commitments and Contingencies (Tables) Sheet http://www.centerpointenergy.com/role/CommitmentsandContingenciesTables Commitments and Contingencies (Tables) Tables http://www.centerpointenergy.com/role/CommitmentsandContingencies 61 false false R62.htm 9954486 - Disclosure - Earnings Per Share (CenterPoint Energy) (Tables) Sheet http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergyTables Earnings Per Share (CenterPoint Energy) (Tables) Tables http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergy 62 false false R63.htm 9954487 - Disclosure - Reportable Segments (Tables) Sheet http://www.centerpointenergy.com/role/ReportableSegmentsTables Reportable Segments (Tables) Tables http://www.centerpointenergy.com/role/ReportableSegments 63 false false R64.htm 9954488 - Disclosure - Supplemental Disclosure of Cash Flow and Balance Sheet Information (Tables) Sheet http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformationTables Supplemental Disclosure of Cash Flow and Balance Sheet Information (Tables) Tables http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformation 64 false false R65.htm 9954489 - Disclosure - Related Party Transactions (Houston Electric and CERC) (Tables) Sheet http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables Related Party Transactions (Houston Electric and CERC) (Tables) Tables http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERC 65 false false R66.htm 9954490 - Disclosure - Leases (Tables) Sheet http://www.centerpointenergy.com/role/LeasesTables Leases (Tables) Tables http://www.centerpointenergy.com/role/Leases 66 false false R67.htm 9954491 - Disclosure - Background (Details) Sheet http://www.centerpointenergy.com/role/BackgroundDetails Background (Details) Details http://www.centerpointenergy.com/role/Background 67 false false R68.htm 9954492 - Disclosure - Summary of Significant Accounting Policies (Details) Sheet http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPoliciesDetails Summary of Significant Accounting Policies (Details) Details http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPoliciesTables 68 false false R69.htm 9954493 - Disclosure - Summary of Significant Accounting Policies - LIFO Inventory (Details) Sheet http://www.centerpointenergy.com/role/SummaryofSignificantAccountingPoliciesLIFOInventoryDetails Summary of Significant Accounting Policies - LIFO Inventory (Details) Details 69 false false R70.htm 9954494 - Disclosure - Property, Plant and Equipment (Details) Sheet http://www.centerpointenergy.com/role/PropertyPlantandEquipmentDetails Property, Plant and Equipment (Details) Details http://www.centerpointenergy.com/role/PropertyPlantandEquipmentTables 70 false false R71.htm 9954495 - Disclosure - Divestitures (CenterPoint Energy and CERC) - Divestitures Narrative (Details) Sheet http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCDivestituresNarrativeDetails Divestitures (CenterPoint Energy and CERC) - Divestitures Narrative (Details) Details http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCTables 71 false false R72.htm 9954496 - Disclosure - Divestitures (CenterPoint Energy and CERC) - Schedule of Pre-tax Income (Details) Sheet http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCScheduleofPretaxIncomeDetails Divestitures (CenterPoint Energy and CERC) - Schedule of Pre-tax Income (Details) Details http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCTables 72 false false R73.htm 9954497 - Disclosure - Divestitures (CenterPoint Energy and CERC) - Summary of Discontinued Operations (Details) Sheet http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCSummaryofDiscontinuedOperationsDetails Divestitures (CenterPoint Energy and CERC) - Summary of Discontinued Operations (Details) Details http://www.centerpointenergy.com/role/DivestituresCenterPointEnergyandCERCTables 73 false false R74.htm 9954498 - Disclosure - Revenue Recognition - Disaggregation of Revenue (Details) Sheet http://www.centerpointenergy.com/role/RevenueRecognitionDisaggregationofRevenueDetails Revenue Recognition - Disaggregation of Revenue (Details) Details 74 false false R75.htm 9954499 - Disclosure - Revenue Recognition - Summary of Contract Assets and Liabilities (Details) Sheet http://www.centerpointenergy.com/role/RevenueRecognitionSummaryofContractAssetsandLiabilitiesDetails Revenue Recognition - Summary of Contract Assets and Liabilities (Details) Details 75 false false R76.htm 9954500 - Disclosure - Revenue Recognition - Schedule of Bad Debt Expense (Details) Sheet http://www.centerpointenergy.com/role/RevenueRecognitionScheduleofBadDebtExpenseDetails Revenue Recognition - Schedule of Bad Debt Expense (Details) Details 76 false false R77.htm 9954501 - Disclosure - Goodwill and Other Intangibles (CenterPoint Energy and CERC) (Details) Sheet http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERCDetails Goodwill and Other Intangibles (CenterPoint Energy and CERC) (Details) Details http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERCTables 77 false false R78.htm 9954502 - Disclosure - Goodwill and Other Intangibles (CenterPoint Energy and CERC) - Narrative (Details) Sheet http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERCNarrativeDetails Goodwill and Other Intangibles (CenterPoint Energy and CERC) - Narrative (Details) Details http://www.centerpointenergy.com/role/GoodwillandOtherIntangiblesCenterPointEnergyandCERCTables 78 false false R79.htm 9954503 - Disclosure - Regulatory Matters - Schedule of Regulatory Assets and Liabilities (Details) Sheet http://www.centerpointenergy.com/role/RegulatoryMattersScheduleofRegulatoryAssetsandLiabilitiesDetails Regulatory Matters - Schedule of Regulatory Assets and Liabilities (Details) Details 79 false false R80.htm 9954504 - Disclosure - Regulatory Matters - Schedule of Allowed Equity Return Recognized (Details) Sheet http://www.centerpointenergy.com/role/RegulatoryMattersScheduleofAllowedEquityReturnRecognizedDetails Regulatory Matters - Schedule of Allowed Equity Return Recognized (Details) Details 80 false false R81.htm 9954505 - Disclosure - Regulatory Matters - Narrative (Details) Sheet http://www.centerpointenergy.com/role/RegulatoryMattersNarrativeDetails Regulatory Matters - Narrative (Details) Details 81 false false R82.htm 9954506 - Disclosure - Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Stock Based Incentive Compensation (Details) Sheet http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlansStockBasedIncentiveCompensationDetails Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Stock Based Incentive Compensation (Details) Details 82 false false R83.htm 9954507 - Disclosure - Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Pension and Postretirement Benefits (Details) Sheet http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlansPensionandPostretirementBenefitsDetails Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Pension and Postretirement Benefits (Details) Details 83 false false R84.htm 9954508 - Disclosure - Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Plan Assets (Details) Sheet http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlansPlanAssetsDetails Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Plan Assets (Details) Details http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlansTables 84 false false R85.htm 9954509 - Disclosure - Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Change in Control Agreements and Other Employee Matters (Details) Sheet http://www.centerpointenergy.com/role/StockBasedIncentiveCompensationPlansandEmployeeBenefitPlansChangeinControlAgreementsandOtherEmployeeMattersDetails Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Change in Control Agreements and Other Employee Matters (Details) Details 85 false false R86.htm 9954510 - Disclosure - Derivative Instruments - Narrative (Details) Sheet http://www.centerpointenergy.com/role/DerivativeInstrumentsNarrativeDetails Derivative Instruments - Narrative (Details) Details 86 false false R87.htm 9954511 - Disclosure - Derivative Instruments - Interest Rate Hedging and Weather Hedges (Details) Sheet http://www.centerpointenergy.com/role/DerivativeInstrumentsInterestRateHedgingandWeatherHedgesDetails Derivative Instruments - Interest Rate Hedging and Weather Hedges (Details) Details 87 false false R88.htm 9954512 - Disclosure - Derivative Instruments - Summary of Derivative Activity (Details) Sheet http://www.centerpointenergy.com/role/DerivativeInstrumentsSummaryofDerivativeActivityDetails Derivative Instruments - Summary of Derivative Activity (Details) Details 88 false false R89.htm 9954513 - Disclosure - Fair Value Measurements - Schedule of Assets and Liabilities Measured On Recurring Basis (Details) Sheet http://www.centerpointenergy.com/role/FairValueMeasurementsScheduleofAssetsandLiabilitiesMeasuredOnRecurringBasisDetails Fair Value Measurements - Schedule of Assets and Liabilities Measured On Recurring Basis (Details) Details 89 false false R90.htm 9954514 - Disclosure - Fair Value Measurements - Schedule of Estimated Fair Value of Financial Instruments (Details) Sheet http://www.centerpointenergy.com/role/FairValueMeasurementsScheduleofEstimatedFairValueofFinancialInstrumentsDetails Fair Value Measurements - Schedule of Estimated Fair Value of Financial Instruments (Details) Details 90 false false R91.htm 9954515 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Gain (Loss) On Equity Securities (CenterPoint Energy) (Details) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyScheduleofGainLossOnEquitySecuritiesCenterPointEnergyDetails Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Gain (Loss) On Equity Securities (CenterPoint Energy) (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 91 false false R92.htm 9954516 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Narrative (Details) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyNarrativeDetails Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Narrative (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 92 false false R93.htm 9954517 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Securities Classified as Trading (Details) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyScheduleofSecuritiesClassifiedasTradingDetails Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Securities Classified as Trading (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 93 false false R94.htm 9954518 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Reference Shares (Details) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyScheduleofReferenceSharesDetails Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Reference Shares (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 94 false false R95.htm 9954519 - Disclosure - Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Summarized Financial Information (Details) Sheet http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergySummarizedFinancialInformationDetails Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Summarized Financial Information (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 95 false false R96.htm 9954520 - Disclosure - Equity (CenterPoint Energy) (Details) Sheet http://www.centerpointenergy.com/role/EquityCenterPointEnergyDetails Equity (CenterPoint Energy) (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 96 false false R97.htm 9954521 - Disclosure - Equity (CenterPoint Energy) - Narrative (Details) Sheet http://www.centerpointenergy.com/role/EquityCenterPointEnergyNarrativeDetails Equity (CenterPoint Energy) - Narrative (Details) Details http://www.centerpointenergy.com/role/EquitySecuritiesandIndexedDebtSecuritiesZENSCenterPointEnergyTables 97 false false R98.htm 9954522 - Disclosure - Short-term Borrowings and Long-term Debt - Schedule of Debt (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtScheduleofDebtDetails Short-term Borrowings and Long-term Debt - Schedule of Debt (Details) Details 98 false false R99.htm 9954523 - Disclosure - Short-term Borrowings and Long-term Debt - Debt Transactions (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtDebtTransactionsDetails Short-term Borrowings and Long-term Debt - Debt Transactions (Details) Details 99 false false R100.htm 9954524 - Disclosure - Short-term Borrowings and Long-term Debt - Narrative (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtNarrativeDetails Short-term Borrowings and Long-term Debt - Narrative (Details) Details 100 false false R101.htm 9954525 - Disclosure - Short-term Borrowings and Long-term Debt - Debt Repayments and Redemptions (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtDebtRepaymentsandRedemptionsDetails Short-term Borrowings and Long-term Debt - Debt Repayments and Redemptions (Details) Details 101 false false R102.htm 9954526 - Disclosure - Short-term Borrowings and Long-term Debt - Early Extinguishment of Debt (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtEarlyExtinguishmentofDebtDetails Short-term Borrowings and Long-term Debt - Early Extinguishment of Debt (Details) Details 102 false false R103.htm 9954527 - Disclosure - Short-term Borrowings and Long-term Debt - Schedule of Revolving Credit Facilities (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtScheduleofRevolvingCreditFacilitiesDetails Short-term Borrowings and Long-term Debt - Schedule of Revolving Credit Facilities (Details) Details 103 false false R104.htm 9954528 - Disclosure - Short-term Borrowings and Long-term Debt - Schedule of Maturities (Details) Sheet http://www.centerpointenergy.com/role/ShorttermBorrowingsandLongtermDebtScheduleofMaturitiesDetails Short-term Borrowings and Long-term Debt - Schedule of Maturities (Details) Details 104 false false R105.htm 9954529 - Disclosure - Income Taxes - Components of Income Tax Expense (Benefit) (Details) Sheet http://www.centerpointenergy.com/role/IncomeTaxesComponentsofIncomeTaxExpenseBenefitDetails Income Taxes - Components of Income Tax Expense (Benefit) (Details) Details 105 false false R106.htm 9954530 - Disclosure - Income Taxes - Schedule of Income Tax Reconciliation (Details) Sheet http://www.centerpointenergy.com/role/IncomeTaxesScheduleofIncomeTaxReconciliationDetails Income Taxes - Schedule of Income Tax Reconciliation (Details) Details 106 false false R107.htm 9954531 - Disclosure - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) Sheet http://www.centerpointenergy.com/role/IncomeTaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) Details 107 false false R108.htm 9954532 - Disclosure - Income Taxes - Narrative (Details) Sheet http://www.centerpointenergy.com/role/IncomeTaxesNarrativeDetails Income Taxes - Narrative (Details) Details 108 false false R109.htm 9954533 - Disclosure - Income Taxes - Schedule of Unrecognized Tax Benefits (Details) Sheet http://www.centerpointenergy.com/role/IncomeTaxesScheduleofUnrecognizedTaxBenefitsDetails Income Taxes - Schedule of Unrecognized Tax Benefits (Details) Details 109 false false R110.htm 9954534 - Disclosure - Commitments and Contingencies - Narrative (Details) Sheet http://www.centerpointenergy.com/role/CommitmentsandContingenciesNarrativeDetails Commitments and Contingencies - Narrative (Details) Details 110 false false R111.htm 9954535 - Disclosure - Commitments and Contingencies - Purchase Obligations (Details) Sheet http://www.centerpointenergy.com/role/CommitmentsandContingenciesPurchaseObligationsDetails Commitments and Contingencies - Purchase Obligations (Details) Details 111 false false R112.htm 9954536 - Disclosure - Commitments and Contingencies - Schedule of Estimated Accrued Costs (Details) Sheet http://www.centerpointenergy.com/role/CommitmentsandContingenciesScheduleofEstimatedAccruedCostsDetails Commitments and Contingencies - Schedule of Estimated Accrued Costs (Details) Details 112 false false R113.htm 9954537 - Disclosure - Earnings Per Share (CenterPoint Energy) (Details) Sheet http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergyDetails Earnings Per Share (CenterPoint Energy) (Details) Details http://www.centerpointenergy.com/role/EarningsPerShareCenterPointEnergyTables 113 false false R114.htm 9954538 - Disclosure - Reportable Segments - Financial Data (Details) Sheet http://www.centerpointenergy.com/role/ReportableSegmentsFinancialDataDetails Reportable Segments - Financial Data (Details) Details 114 false false R115.htm 9954539 - Disclosure - Reportable Segments - Revenues From Major External Customers (Details) Sheet http://www.centerpointenergy.com/role/ReportableSegmentsRevenuesFromMajorExternalCustomersDetails Reportable Segments - Revenues From Major External Customers (Details) Details 115 false false R116.htm 9954540 - Disclosure - Reportable Segments - Revenues by Products and Services (Details) Sheet http://www.centerpointenergy.com/role/ReportableSegmentsRevenuesbyProductsandServicesDetails Reportable Segments - Revenues by Products and Services (Details) Details 116 false false R117.htm 9954541 - Disclosure - Supplemental Disclosure of Cash Flow and Balance Sheet Information (Details) Sheet http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformationDetails Supplemental Disclosure of Cash Flow and Balance Sheet Information (Details) Details http://www.centerpointenergy.com/role/SupplementalDisclosureofCashFlowandBalanceSheetInformationTables 117 false false R118.htm 9954542 - Disclosure - Related Party Transactions (Houston Electric and CERC) - Schedule of Money Pool Investments (Details) Sheet http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCScheduleofMoneyPoolInvestmentsDetails Related Party Transactions (Houston Electric and CERC) - Schedule of Money Pool Investments (Details) Details http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables 118 false false R119.htm 9954543 - Disclosure - Related Party Transactions (Houston Electric and CERC) - Schedule of Affiliated-Related Net Interest Income (Expense) (Details) Sheet http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCScheduleofAffiliatedRelatedNetInterestIncomeExpenseDetails Related Party Transactions (Houston Electric and CERC) - Schedule of Affiliated-Related Net Interest Income (Expense) (Details) Details http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables 119 false false R120.htm 9954544 - Disclosure - Related Party Transactions (Houston Electric and CERC) - Schedule of Amounts Charged For Services (Details) Sheet http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCScheduleofAmountsChargedForServicesDetails Related Party Transactions (Houston Electric and CERC) - Schedule of Amounts Charged For Services (Details) Details http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables 120 false false R121.htm 9954545 - Disclosure - Related Party Transactions (Houston Electric and CERC) - Schedule of Transactions (Details) Sheet http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCScheduleofTransactionsDetails Related Party Transactions (Houston Electric and CERC) - Schedule of Transactions (Details) Details http://www.centerpointenergy.com/role/RelatedPartyTransactionsHoustonElectricandCERCTables 121 false false R122.htm 9954546 - Disclosure - Leases (Details) Sheet http://www.centerpointenergy.com/role/LeasesDetails Leases (Details) Details http://www.centerpointenergy.com/role/LeasesTables 122 false false R123.htm 9954547 - Disclosure - Subsequent Events (Details) Sheet http://www.centerpointenergy.com/role/SubsequentEventsDetails Subsequent Events (Details) Details http://www.centerpointenergy.com/role/SubsequentEvents 123 false false All Reports Book All Reports cnp-20231231.htm cnp-20231231.xsd cnp-20231231_cal.xml cnp-20231231_def.xml cnp-20231231_lab.xml cnp-20231231_pre.xml http://fasb.org/us-gaap/2023 http://xbrl.sec.gov/dei/2023 http://xbrl.sec.gov/ecd/2023 true true