CENTERPOINT ENERGY INC Presentation Networks

Line Image Concept Label Concept Type Period type Balance Concept name
* Network: (100 - Statement - CONDENSED STATEMENTS OF CONSOLIDATED INCOME)
1 cnp: Condensed Statements Of Consolidated Income xbrli:stringItemType duration cnp:CondensedStatementsOfConsolidatedIncome
2 us-gaap: Revenues xbrli:monetaryItemType duration credit us-gaap:Revenues
3 cnp: Expenses: xbrli:stringItemType duration cnp:Expenses
4 us-gaap: Natural gas xbrli:monetaryItemType duration debit us-gaap:CostOfPurchasedOilAndGas
5 cnp: Operation and maintenance xbrli:monetaryItemType duration cnp:OperationAndMaintenance
6 us-gaap: Depreciation and amortization xbrli:monetaryItemType duration debit us-gaap:DepreciationAndAmortization
7 us-gaap: Taxes other than income taxes xbrli:monetaryItemType duration debit us-gaap:TaxesOtherThanIncomeExciseProductionAndPropertyTaxes
8 us-gaap: Total xbrli:monetaryItemType duration debit us-gaap:OperatingExpenses
9 us-gaap: Operating Income xbrli:monetaryItemType duration credit us-gaap:OperatingIncomeLoss
10 cnp: Other Income (Expense): xbrli:stringItemType duration cnp:OtherIncomeExpense
11 us-gaap: Gain (loss) on marketable securities xbrli:monetaryItemType duration credit us-gaap:MarketableSecuritiesGainLoss
12 cnp: Gain (loss) on indexed debt securities xbrli:monetaryItemType duration cnp:GainLossOnIndexedDebtSecurities
13 us-gaap: Interest and other finance charges xbrli:monetaryItemType duration debit us-gaap:InterestAndDebtExpense
14 cnp: Interest on transition bonds xbrli:monetaryItemType duration cnp:InterestOnTransitionBonds
15 us-gaap: Equity in earnings of unconsolidated affiliates xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromEquityMethodInvestments
16 us-gaap: Distribution from AOL Time Warner litigation settlement xbrli:monetaryItemType duration credit us-gaap:GainLossRelatedToLitigationSettlement
17 us-gaap: Additional distribution to ZENS holders xbrli:monetaryItemType duration debit us-gaap:InterestExpenseOther
18 us-gaap: Return on true-up balance xbrli:monetaryItemType duration debit us-gaap:RecoveryStrandedCosts
19 us-gaap: Other, net xbrli:monetaryItemType duration credit us-gaap:OtherNonoperatingIncomeExpense
20 us-gaap: Total xbrli:monetaryItemType duration credit us-gaap:NonoperatingIncomeExpense
21 us-gaap: Income Before Income Taxes xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
22 us-gaap: Income tax expense xbrli:monetaryItemType duration debit us-gaap:IncomeTaxExpenseBenefit
23 us-gaap: Income From Continuing Operations Before Extraordinary Item xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromContinuingOperations
24 us-gaap: Income from Texas Genco, net of tax xbrli:monetaryItemType duration credit us-gaap:DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax
25 us-gaap: Loss on disposal of Texas Genco, net of tax xbrli:monetaryItemType duration credit us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
26 us-gaap: Total xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax
27 us-gaap: Income Before Extraordinary Item xbrli:monetaryItemType duration credit us-gaap:IncomeLossBeforeExtraordinaryItemsAndCumulativeEffectOfChangeInAccountingPrinciple
28 us-gaap: Extraordinary item, net of tax xbrli:monetaryItemType duration credit us-gaap:ExtraordinaryItemNetOfTax
29 us-gaap: Net Income xbrli:monetaryItemType duration credit us-gaap:NetIncomeLoss
30 us-gaap: Net Income xbrli:monetaryItemType duration credit us-gaap:ProfitLoss
31 us-gaap: Income From Continuing Operations Before Extraordinary Item us-types:perShareItemType duration us-gaap:IncomeLossBeforeExtraordinaryItemsAndCumulativeEffectOfChangeInAccountingPrinciplePerBasicShare
32 us-gaap: Discontinued Operations, net of tax us-types:perShareItemType duration us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare
33 us-gaap: Extraordinary item, net of tax us-types:perShareItemType duration us-gaap:IncomeLossFromExtraordinaryItemsNetOfTaxPerBasicShare
34 us-gaap: Basic Earnings Per Share us-types:perShareItemType duration us-gaap:EarningsPerShareBasic
35 us-gaap: Income From Continuing Operations Before Extraordinary Item us-types:perShareItemType duration us-gaap:IncomeLossBeforeExtraordinaryItemsAndCumulativeEffectOfChangeInAccountingPrinciplePerDilutedShare
36 us-gaap: Discontinued Operations, net of tax us-types:perShareItemType duration us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare
37 us-gaap: Extraordinary item, net of tax us-types:perShareItemType duration us-gaap:IncomeLossFromExtraordinaryItemsNetOfTaxPerDilutedShare
38 us-gaap: Diluted Earnings Per Share us-types:perShareItemType duration us-gaap:EarningsPerShareDiluted
* Network: (200 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS)
39 cnp: Condensed Consolidated Balance Sheets xbrli:stringItemType duration cnp:CondensedConsolidatedBalanceSheets
40 cnp: Current Assets: xbrli:stringItemType duration cnp:CurrentAssets
41 us-gaap: Cash and cash equivalents xbrli:monetaryItemType instant debit us-gaap:CashAndCashEquivalentsAtCarryingValue
42 us-gaap: Investment in marketable securities xbrli:monetaryItemType instant debit us-gaap:MarketableSecuritiesCurrent
43 us-gaap: Accounts receivable, net xbrli:monetaryItemType instant debit us-gaap:AccountsReceivableNetCurrent
44 us-gaap: Investment in Time Warner common stock xbrli:monetaryItemType instant debit us-gaap:TradingSecuritiesEquityCurrent
45 cnp: Accrued unbilled revenues xbrli:monetaryItemType instant cnp:AccruedUnbilledRevenues
46 us-gaap: Natural gas inventory xbrli:monetaryItemType instant debit us-gaap:EnergyRelatedInventoryNaturalGasInStorage
47 cnp: Materials and supplies xbrli:monetaryItemType instant cnp:MaterialsAndSupplies
48 us-gaap: Inventory xbrli:monetaryItemType instant debit us-gaap:InventoryNet
49 us-gaap: Non-trading derivative assets xbrli:monetaryItemType instant debit us-gaap:DerivativeAssetsCurrent
50 us-gaap: Taxes receivable xbrli:monetaryItemType instant debit us-gaap:IncomeTaxesReceivable
51 us-gaap: Prepaid expenses and other current assets xbrli:monetaryItemType instant debit us-gaap:OtherAssetsCurrent
52 us-gaap: Total current assets xbrli:monetaryItemType instant debit us-gaap:AssetsCurrent
53 us-gaap: Property, Plant and Equipment: xbrli:stringItemType duration us-gaap:PropertyPlantAndEquipmentAbstract
54 us-gaap: Property, plant and equipment xbrli:monetaryItemType instant debit us-gaap:PropertyPlantAndEquipmentGross
55 us-gaap: Less accumulated depreciation and amortization xbrli:monetaryItemType instant credit us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
56 us-gaap: Property, plant and equipment, net xbrli:monetaryItemType instant debit us-gaap:PropertyPlantAndEquipmentNet
57 cnp: Other Assets: xbrli:stringItemType duration cnp:OtherAssetsAbstract
58 us-gaap: Goodwill xbrli:monetaryItemType instant debit us-gaap:Goodwill
59 us-gaap: Regulatory assets xbrli:monetaryItemType instant debit us-gaap:RegulatoryAssetsNoncurrent
60 us-gaap: Non-trading derivative assets xbrli:monetaryItemType instant debit us-gaap:DerivativeAssetsNoncurrent
61 us-gaap: Investment in unconsolidated affiliates xbrli:monetaryItemType instant debit us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
62 us-gaap: Notes receivable from unconsolidated affiliates xbrli:monetaryItemType instant debit us-gaap:AdvancesToAffiliate
63 us-gaap: Other xbrli:monetaryItemType instant debit us-gaap:OtherAssetsNoncurrent
64 us-gaap: Total other assets xbrli:monetaryItemType instant debit us-gaap:AssetsNoncurrent
65 us-gaap: Total Assets xbrli:monetaryItemType instant debit us-gaap:Assets
66 cnp: Current Liabilities: xbrli:stringItemType duration cnp:CurrentLiabilitiesAbstract
67 us-gaap: Short-term borrowings xbrli:monetaryItemType instant credit us-gaap:ShortTermBorrowings
68 us-gaap: Current portion of transition bond long-term debt xbrli:monetaryItemType instant credit us-gaap:LongtermTransitionBondCurrent
69 us-gaap: Current portion of other long-term debt xbrli:monetaryItemType instant credit us-gaap:OtherLongTermDebtCurrent
70 us-gaap: Current portion of other long-term debt xbrli:monetaryItemType instant credit us-gaap:LongTermDebtCurrent
71 cnp: Indexed debt securities derivative xbrli:monetaryItemType instant cnp:IndexedDebtSecuritiesDerivative
72 us-gaap: Accounts payable xbrli:monetaryItemType instant credit us-gaap:AccountsPayable
73 us-gaap: Taxes accrued xbrli:monetaryItemType instant credit us-gaap:TaxesPayable
74 us-gaap: Interest accrued xbrli:monetaryItemType instant credit us-gaap:InterestPayable
75 us-gaap: Non-trading derivative liabilities xbrli:monetaryItemType instant credit us-gaap:DerivativeLiabilitiesCurrent
76 us-gaap: Accumulated deferred income taxes, net xbrli:monetaryItemType instant credit us-gaap:DeferredTaxLiabilitiesCurrent
77 us-gaap: Other xbrli:monetaryItemType instant credit us-gaap:OtherLiabilitiesCurrent
78 us-gaap: Total current liabilities xbrli:monetaryItemType instant credit us-gaap:LiabilitiesCurrent
79 cnp: Other Liabilities: xbrli:stringItemType duration cnp:OtherLiabilitiesAbstract
80 us-gaap: Accumulated deferred income taxes, net xbrli:monetaryItemType instant credit us-gaap:DeferredTaxLiabilitiesNoncurrent
81 us-gaap: Unamortized investment tax credits xbrli:monetaryItemType instant credit us-gaap:AccumulatedDeferredInvestmentTaxCredit
82 us-gaap: Non-trading derivative liabilities xbrli:monetaryItemType instant credit us-gaap:DerivativeLiabilitiesNoncurrent
83 us-gaap: Benefit obligations xbrli:monetaryItemType instant credit us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilities
84 us-gaap: Regulatory liabilities xbrli:monetaryItemType instant credit us-gaap:RegulatoryLiabilityNoncurrent
85 us-gaap: Other xbrli:monetaryItemType instant credit us-gaap:OtherLiabilitiesNoncurrent
86 us-gaap: Total other liabilities xbrli:monetaryItemType instant credit us-gaap:LiabilitiesNoncurrent
87 us-gaap: Long-term Debt: xbrli:stringItemType duration us-gaap:LongTermDebtAbstract
88 us-gaap: Transition bonds xbrli:monetaryItemType instant credit us-gaap:LongTermTransitionBond
89 us-gaap: Other xbrli:monetaryItemType instant credit us-gaap:OtherLongTermDebtNoncurrent
90 us-gaap: Total long-term debt xbrli:monetaryItemType instant credit us-gaap:LongTermDebtNoncurrent
91 us-gaap: Commitments and Contingencies xbrli:stringItemType duration us-gaap:CommitmentsAndContingencies2009
92 cnp: Shareholders' Equity: xbrli:stringItemType duration cnp:ShareholdersEquityAbstract
93 us-gaap: Common stock (346,088,548 shares and 390,331,500 shares outstanding at December 31, 2008 and September 30, 2009, respectively) xbrli:monetaryItemType instant credit us-gaap:CommonStockValue
94 us-gaap: Additional paid-in capital xbrli:monetaryItemType instant credit us-gaap:AdditionalPaidInCapital
95 us-gaap: Accumulated deficit xbrli:monetaryItemType instant credit us-gaap:RetainedEarningsAccumulatedDeficit
96 us-gaap: Accumulated other comprehensive loss xbrli:monetaryItemType instant credit us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
97 us-gaap: Total shareholders' equity xbrli:monetaryItemType instant credit us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
98 us-gaap: Shareholders' Equity xbrli:monetaryItemType instant credit us-gaap:StockholdersEquity
99 us-gaap: Total Liabilities and Shareholders' Equity xbrli:monetaryItemType instant credit us-gaap:LiabilitiesAndStockholdersEquity
* Network: (210 - Statement - Parenthetical Data For Condensed Consolidated Balance Sheets)
100 cnp: Parenthetical Data For Condensed Consolidated Balance Sheets xbrli:stringItemType duration cnp:ParentheticalDataForCondensedConsolidatedBalanceSheets
101 cnp: Shareholders' Equity [Abstract] xbrli:stringItemType duration cnp:ShareholdersEquityAbstract
102 us-gaap: Common Stock, Shares, Outstanding xbrli:sharesItemType instant us-gaap:CommonStockSharesOutstanding
* Network: (300 - Statement - CONDENSED STATEMENTS OF CONSOLIDATED CASH FLOWS)
103 cnp: Condensed Statements Of Consolidated Cash Flows xbrli:stringItemType duration cnp:CondensedStatementsOfConsolidatedCashFlows
104 cnp: Cash Flows from Operating Activities: xbrli:stringItemType duration cnp:CashFlowsFromOperatingActivities
105 us-gaap: Net income xbrli:monetaryItemType duration credit us-gaap:ProfitLoss
106 us-gaap: Discontinued operations, net of tax xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax
107 us-gaap: Extraordinary item, net of tax xbrli:monetaryItemType duration credit us-gaap:ExtraordinaryItemNetOfTax
108 us-gaap: Income From Continuing Operations Before Extraordinary Item xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromContinuingOperations
109 cnp: Adjustments to reconcile net income to net cash provided by operating activities: xbrli:stringItemType duration cnp:AdjustmentsToReconcileNetIncomeToNetCashProvidedByOperatingActivities
110 us-gaap: Depreciation and amortization xbrli:monetaryItemType duration debit us-gaap:DepreciationAndAmortization
111 us-gaap: Amortization of deferred financing costs xbrli:monetaryItemType duration debit us-gaap:AmortizationOfFinancingCosts
112 us-gaap: Deferred income taxes xbrli:monetaryItemType duration debit us-gaap:DeferredIncomeTaxExpenseBenefit
113 us-gaap: Unrealized loss on marketable securities xbrli:monetaryItemType duration credit us-gaap:MarketableSecuritiesUnrealizedGainLoss
114 cnp: Tax and interest reserves reductions related to ZENS and ACES settlement xbrli:monetaryItemType duration cnp:TaxAndInterestReservesReductionsRelatedToSettlement
115 us-gaap: Investment Tax Credit xbrli:monetaryItemType duration debit us-gaap:InvestmentTaxCredit
116 us-gaap: Unrealized loss (gain) on Time Warner investment xbrli:monetaryItemType duration credit us-gaap:UnrealizedGainLossOnSecurities
117 cnp: Unrealized gain on indexed debt securities xbrli:monetaryItemType duration cnp:UnrealizedLossGainOnIndexedDebtSecurities
118 us-gaap: Write- down of natural gas inventory xbrli:monetaryItemType duration debit us-gaap:InventoryWriteDown
119 us-gaap: Equity in earnings of unconsolidated affiliates, net of distributions xbrli:monetaryItemType duration credit us-gaap:IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions
120 cnp: Changes in other assets and liabilities: xbrli:stringItemType duration cnp:ChangesInOtherAssetsAndLiabilities
121 cnp: Accounts receivable and unbilled revenues, net xbrli:monetaryItemType duration cnp:AccountsReceivableAndUnbilledRevenuesNet
122 us-gaap: Inventory xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInInventories
123 us-gaap: Taxes receivable xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInIncomeTaxesReceivable
124 us-gaap: Accounts payable xbrli:monetaryItemType duration debit us-gaap:IncreaseDecreaseInAccountsPayable
125 us-gaap: Fuel cost over (under) recovery xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInOverUnderEnergyRecovery
126 us-gaap: Non-trading derivatives, net xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInCommodityContractAssetsAndLiabilities
127 cnp: Margin deposits, net xbrli:monetaryItemType duration cnp:MarginDepositsNet
128 cnp: Interest and taxes accrued xbrli:monetaryItemType duration cnp:InterestAndTaxesAccrued
129 us-gaap: Net regulatory assets and liabilities xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities
130 us-gaap: Pension contribution xbrli:monetaryItemType duration debit us-gaap:IncreaseDecreaseInPensionPlanObligations
131 cnp: Other current assets xbrli:monetaryItemType duration cnp:NetChangeOtherCurrentAssets
132 cnp: Other current liabilities xbrli:monetaryItemType duration cnp:NetChangeOtherCurrentLiabilities
133 cnp: Other assets xbrli:monetaryItemType duration cnp:NetChangeOtherAssetsNoncurrent
134 cnp: Other liabilities xbrli:monetaryItemType duration cnp:NetChangeOtherLiabilitiesNoncurrent
135 us-gaap: Other, net xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet
136 us-gaap: Net cash provided by operating activities of continuing operations xbrli:monetaryItemType duration us-gaap:NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
137 us-gaap: Net cash used in operating activities of discontinued operations xbrli:monetaryItemType duration debit us-gaap:CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations
138 us-gaap: Net cash provided by operating activities xbrli:monetaryItemType duration us-gaap:NetCashProvidedByUsedInOperatingActivities
139 cnp: Cash Flows from Investing Activities: xbrli:stringItemType duration cnp:CashFlowsFromInvestingActivities
140 us-gaap: Capital expenditures xbrli:monetaryItemType duration credit us-gaap:PaymentsToAcquireProductiveAssets
141 us-gaap: Proceeds from sale of Texas Genco xbrli:monetaryItemType duration debit us-gaap:ProceedsFromDivestitureOfBusinesses
142 us-gaap: Purchase of minority interest of Texas Genco xbrli:monetaryItemType duration credit us-gaap:PaymentsToAcquireAdditionalInterestInSubsidiaries
143 us-gaap: Decrease in restricted cash for purchase of minority interest of Texas Genco xbrli:monetaryItemType duration debit us-gaap:CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations
144 us-gaap: Decrease (increase) in restricted cash of transition bond companies xbrli:monetaryItemType duration credit us-gaap:IncreaseDecreaseInRestrictedCash
145 us-gaap: Decrease (increase) in notes receivable from unconsolidated affiliates xbrli:monetaryItemType duration credit us-gaap:PaymentsForAdvanceToAffiliate
146 us-gaap: Investment in unconsolidated affiliates xbrli:monetaryItemType duration credit us-gaap:PaymentsToAcquireInterestInJointVenture
147 us-gaap: Other, net xbrli:monetaryItemType duration credit us-gaap:PaymentsForProceedsFromOtherInvestingActivities
148 us-gaap: Net cash used in investing activities xbrli:monetaryItemType duration debit us-gaap:NetCashProvidedByUsedInInvestingActivities
149 cnp: Cash Flows from Financing Activities: xbrli:stringItemType duration cnp:CashFlowsFromFinancingActivities
150 cnp: Increase (decrease) in short-term borrowings, net xbrli:monetaryItemType duration cnp:IncreaseInShortTermBorrowingsNet
151 cnp: Long-term revolving credit facilities, net xbrli:monetaryItemType duration cnp:LongTermRevolvingCreditFacilityNet
152 us-gaap: Proceeds from commercial paper, net xbrli:monetaryItemType duration debit us-gaap:ProceedsFromIssuanceOfCommercialPaper
153 us-gaap: Proceeds from long-term debt xbrli:monetaryItemType duration debit us-gaap:ProceedsFromIssuanceOfLongTermDebt
154 us-gaap: Payments of long-term debt xbrli:monetaryItemType duration credit us-gaap:RepaymentsOfLongTermDebt
155 us-gaap: Debt issuance costs xbrli:monetaryItemType duration credit us-gaap:PaymentsOfDebtIssuanceCosts
156 us-gaap: Payment of common stock dividends xbrli:monetaryItemType duration credit us-gaap:PaymentsOfDividendsCommonStock
157 us-gaap: Proceeds from issuance of common stock, net xbrli:monetaryItemType duration debit us-gaap:ProceedsFromIssuanceOfCommonStock
158 us-gaap: Other, net xbrli:monetaryItemType duration debit us-gaap:ProceedsFromPaymentsForOtherFinancingActivities
159 us-gaap: Net cash provided by (used in) financing activities xbrli:monetaryItemType duration debit us-gaap:NetCashProvidedByUsedInFinancingActivities
160 us-gaap: Net Increase (Decrease) in Cash and Cash Equivalents xbrli:monetaryItemType duration us-gaap:CashAndCashEquivalentsPeriodIncreaseDecrease
161 us-gaap: Cash and Cash Equivalents at Beginning of Period xbrli:monetaryItemType instant debit us-gaap:CashAndCashEquivalentsAtCarryingValue
162 us-gaap: Cash and Cash Equivalents at End of Period xbrli:monetaryItemType instant debit us-gaap:CashAndCashEquivalentsAtCarryingValue
163 cnp: Supplemental Disclosure of Cash Flow Information: xbrli:stringItemType duration cnp:SupplementalDisclosureOfCashFlowInformation
164 cnp: Cash Payments: xbrli:stringItemType duration cnp:CashPayments
165 us-gaap: Interest, net of capitalized interest xbrli:monetaryItemType duration credit us-gaap:InterestPaidNet
166 us-gaap: Income taxes, net xbrli:monetaryItemType duration credit us-gaap:IncomeTaxesPaidNet
167 cnp: Non-cash transactions: xbrli:stringItemType duration cnp:NonCashTransactions
168 us-gaap: Accounts payable related to capital expenditures xbrli:monetaryItemType duration credit us-gaap:CapitalExpendituresIncurredButNotYetPaid
* Network: (600 - Disclosure - Background and Basis of Presentation)
169 cnp: Background and Basis of Presentation [Abstract] xbrli:stringItemType duration cnp:BackgroundAndBasisOfPresentationAbstract
170 us-gaap: Background and Basis of Presentation us-types:textBlockItemType duration us-gaap:OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock
* Network: (601 - Disclosure - New Accounting Pronouncements)
171 cnp: New Accounting Pronouncements [Abstract] xbrli:stringItemType duration cnp:NewAccountingPronouncementsAbstract
172 us-gaap: New Accounting Pronouncements us-types:textBlockItemType duration us-gaap:ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock
* Network: (602 - Disclosure - Employee Benefit Plans)
173 us-gaap: Employee Benefit Plans [Abstract] xbrli:stringItemType duration us-gaap:PensionAndOtherPostretirementBenefitExpenseAbstract
174 us-gaap: Employee Benefit Plans us-types:textBlockItemType duration us-gaap:PensionAndOtherPostretirementBenefitsDisclosureTextBlock
* Network: (603 - Disclosure - Regulatory Matters)
175 us-gaap: Regulatory Matters [Abstract] xbrli:stringItemType duration us-gaap:PublicUtilitiesGeneralDisclosuresAbstract
176 us-gaap: Regulatory Matters us-types:textBlockItemType duration us-gaap:PublicUtilitiesDisclosureTextBlock
* Network: (604 - Disclosure - Derivative Instruments)
177 us-gaap: Derivative Instruments [Abstract] xbrli:stringItemType duration us-gaap:DerivativeInstrumentDetailAbstract
178 us-gaap: Derivative Instruments us-types:textBlockItemType duration us-gaap:DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock
* Network: (605 - Disclosure - Fair Value Measurements)
179 cnp: Fair Value Measurements [Abstract] xbrli:stringItemType duration cnp:FairValueMeasurementsAbstract
180 us-gaap: Fair Value Measurements us-types:textBlockItemType duration us-gaap:FairValueDisclosuresTextBlock
* Network: (606 - Disclosure - Goodwill)
181 cnp: Goodwill [Abstract] xbrli:stringItemType duration cnp:GoodwillAbstract
182 us-gaap: Goodwill us-types:textBlockItemType duration us-gaap:ScheduleOfGoodwillTextBlock
* Network: (607 - Disclosure - Comprehensive Income)
183 us-gaap: Comprehensive Income [Abstract] xbrli:stringItemType duration us-gaap:ComprehensiveIncomeNoteAbstract
184 us-gaap: Comprehensive Income us-types:textBlockItemType duration us-gaap:ComprehensiveIncomeNoteTextBlock
* Network: (608 - Disclosure - Capital Stock)
185 us-gaap: Capital Stock [Abstract] xbrli:stringItemType duration us-gaap:StockholdersEquityNoteAbstract
186 us-gaap: Capital Stock us-types:textBlockItemType duration us-gaap:StockholdersEquityNoteDisclosureTextBlock
* Network: (609 - Disclosure - Short-term Borrowings and Long-term Debt)
187 cnp: Short-term Borrowings and Long-term Debt [Abstract] xbrli:stringItemType duration cnp:ShortTermBorrowingsAndLongTermDebtAbstract
188 us-gaap: Short-term Borrowings and Long-term Debt us-types:textBlockItemType duration us-gaap:DebtDisclosureTextBlock
* Network: (610 - Disclosure - Commitments and Contingencies)
189 cnp: Commitments and Contingencies [Abstract] xbrli:stringItemType duration cnp:CommitmentsAndContingenciesAbstract
190 us-gaap: Commitments and Contingencies us-types:textBlockItemType duration us-gaap:CommitmentsAndContingenciesDisclosureTextBlock
* Network: (611 - Disclosure - Income Taxes)
191 cnp: Income Taxes [Abstract] xbrli:stringItemType duration cnp:IncomeTaxesAbstract
192 us-gaap: Income Taxes us-types:textBlockItemType duration us-gaap:IncomeTaxDisclosureTextBlock
* Network: (612 - Disclosure - Estimated Fair Value of Financial Instruments)
193 cnp: Estimated Fair Value of Financial Instruments [Abstract] xbrli:stringItemType duration cnp:EstimatedFairValueOfFinancialInstrumentsAbstract
194 us-gaap: Estimated Fair Value of Financial Instruments us-types:textBlockItemType duration us-gaap:FairValueOptionTextBlock
* Network: (613 - Disclosure - Earnings Per Share)
195 us-gaap: Earnings Per Share [Abstract] xbrli:stringItemType duration us-gaap:EarningsPerShareAbstract
196 us-gaap: Earnings Per Share us-types:textBlockItemType duration us-gaap:EarningsPerShareTextBlock
* Network: (614 - Disclosure - Reportable Business Segments)
197 cnp: Reportable Business Segments [Abstract] xbrli:stringItemType duration cnp:ReportableBusinessSegmentsAbstract
198 us-gaap: Reportable Business Segments us-types:textBlockItemType duration us-gaap:SegmentReportingDisclosureTextBlock
* Network: (615 - Disclosure - Subsequent Events)
199 cnp: Subsequent Events [Abstract] xbrli:stringItemType duration cnp:SubsequentEventsAbstract
200 us-gaap: Subsequent Events us-types:textBlockItemType duration us-gaap:ScheduleOfSubsequentEventsTextBlock
* Network: (995200 - Document - Document Information)
201 dei: Document Information [Line Items] xbrli:stringItemType duration dei:DocumentInformationLineItems
202 dei: Document Type us-types:SECReportItemType duration dei:DocumentType
203 dei: Document Period End Date xbrli:dateItemType duration dei:DocumentPeriodEndDate
204 dei: Amendment Flag xbrli:booleanItemType duration dei:AmendmentFlag
205 dei: Amendment Description xbrli:stringItemType duration dei:AmendmentDescription
* Network: (995400 - Document - Entity Information)
206 dei: Entity Information [Line Items] xbrli:stringItemType duration dei:EntityInformationLineItems
207 dei: Entity Registrant Name xbrli:normalizedStringItemType duration dei:EntityRegistrantName
208 dei: Entity Central Index Key us-types:centralIndexKeyItemType duration dei:EntityCentralIndexKey
209 dei: Current Fiscal Year End Date xbrli:gMonthDayItemType duration dei:CurrentFiscalYearEndDate
210 dei: Entity Well Known Seasoned Issuer us-types:yesNoItemType duration dei:EntityWellKnownSeasonedIssuer
211 dei: Entity Voluntary Filers us-types:yesNoItemType duration dei:EntityVoluntaryFilers
212 dei: Entity Current Reporting Status us-types:yesNoItemType duration dei:EntityCurrentReportingStatus
213 dei: Entity Filer Category us-types:filerCategoryItemType duration dei:EntityFilerCategory
214 dei: Entity Public Float xbrli:monetaryItemType instant credit dei:EntityPublicFloat
215 dei: Entity Common Stock Shares Outstanding xbrli:sharesItemType instant dei:EntityCommonStockSharesOutstanding