CenterPoint Energy (CNP) 10-Q 1 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Supplement

Document and Entity Supplemental Information Document (USD $)	3 Months Ended
	Mar. 31, 2014	Apr. 15, 2014	Jun. 30, 2013
Entity Information [Line Items]	'	'	'
Entity Registrant Name	'CENTERPOINT ENERGY INC.	'	'
Entity Central Index Key	'0001130310	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Document Type	'10-Q	'	'
Document Period End Date	31-Mar-14	'	'
Document Fiscal Year Focus	'2014	'	'
Document Fiscal Period Focus	'Q1	'	'
Amendment Flag	'false	'	'
Entity Common Stock, Shares Outstanding	'	429,748,467	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Public Float	'	'	$9,975,930,939

Condensed_Statements_of_Consol

Condensed Statements of Consolidated Income (Unaudited) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenues	$3,163	$2,388
Expenses:	'	'
Natural gas	2,043	1,224
Operation and maintenance	479	484
Depreciation and amortization	235	240
Taxes other than income taxes	111	108
Total	2,868	2,056
Operating Income	295	332
Other Income (Expense):	'	'
Gain (loss) on marketable securities	-30	74
Gain (loss) on indexed debt securities	43	-51
Interest and other finance charges	-84	-98
Interest on transition and system restoration bonds	-30	-35
Equity in earnings of unconsolidated affiliates, net	91	5
Other, net	9	6
Total	-1	-99
Income Before Income Taxes	294	233
Income tax expense	109	86
Net Income	$185	$147
Basic Earnings Per Share	$0.43	$0.34
Diluted Earnings Per Share	$0.43	$0.34
Dividends Declared Per Share	$0.24	$0.21
Weighted Average Shares Outstanding, Basic	429,163,000	427,961,000
Weighted Average Shares Outstanding, Diluted	430,559,000	429,672,000

Condensed_Statements_of_Consol1

Condensed Statements of Consolidated Comprehensive Income (Unaudited) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net income	$185	$147
Other comprehensive income:	'	'
Adjustment related to pension and other postretirement plans (net of tax of $1 and $2)	1	3
Total	1	3
Comprehensive income	$186	$150

Condensed_Statements_of_Consol2

Condensed Statements of Consolidated Comprehensive Income Comprehensive Income Parentheticals (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Statement of Comprehensive Income [Abstract]	'	'
Other Comprehensive Income, Pension and Other Postretirement Benefit Plans, Tax	$1	$2

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Current Assets:	'	'
Cash and cash equivalents ($149 and $207 related to VIEs, respectively)	$379	$208
Investment in marketable securities	737	767
Accounts receivable, less bad debt reserve of $35 and $28, respectively ($69 and $60 related to VIEs, respectively)	1,142	851
Accrued unbilled revenues	343	398
Natural gas inventory	26	140
Materials and supplies	146	145
Non-trading derivative assets	24	24
Prepaid expenses and other current assets ($42 and $41 related to VIEs, respectively)	158	125
Total current assets	2,955	2,658
Property, Plant and Equipment:	'	'
Property, plant and equipment	14,368	14,138
Less: accumulated depreciation and amortization	4,605	4,545
Property, plant and equipment, net	9,763	9,593
Other Assets:	'	'
Goodwill	840	840
Regulatory assets ($3,084 and $3,179 related to VIEs, respectively)	3,635	3,726
Notes receivable - affiliated companies	363	363
Non-trading derivative assets	9	10
Investment in unconsolidated affiliates	4,540	4,518
Other	159	162
Total other assets	9,546	9,619
Total Assets	22,264	21,870
Current Liabilities:	'	'
Short-term borrowings	0	43
Current portion of VIE transition and system restoration bonds long-term debt	362	354
Indexed debt	145	143
Indexed debt securities derivative	412	455
Accounts payable	802	689
Taxes accrued	220	184
Interest accrued	107	124
Non-trading derivative liabilities	17	17
Accumulated deferred income taxes, net	629	608
Other	365	402
Total current liabilities	3,059	3,019
Other Liabilities:	'	'
Accumulated deferred income taxes, net	4,528	4,542
Non-trading derivative liabilities	2	4
Benefit obligations	802	802
Regulatory liabilities	1,200	1,152
Other	203	205
Total other liabilities	6,735	6,705
Long-term Debt:	'	'
VIE transition and system restoration bonds	2,908	3,046
Other	5,148	4,771
Total long-term debt	8,056	7,817
Commitments and Contingencies (Note 12)	'	'
Shareholders’ Equity:	'	'
Common stock (429,748,467 shares and 428,798,446 shares outstanding, respectively)	4	4
Additional paid-in capital	4,158	4,157
Retained earnings	341	258
Accumulated other comprehensive loss	-89	-90
Total shareholders’ equity	4,414	4,329
Total Liabilities and Shareholders’ Equity	$22,264	$21,870

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets Balance Sheets Parentheticals (USD $)	3 Months Ended	12 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Total common stock outstanding (in shares)	429,748,467	428,798,446
Cash and cash equivalents	$379	$208
Provision for Doubtful Accounts	35	28
Accounts receivable, net	1,142	851
Prepaid expenses and other current assets	158	125
Regulatory assets	3,635	3,726
Variable Interest Entity, Primary Beneficiary [Member]	'	'
Cash and cash equivalents	149	207
Accounts receivable, net	69	60
Prepaid expenses and other current assets	42	41
Regulatory assets	$3,084	$3,179

Condensed_Statements_of_Consol3

Condensed Statements of Consolidated Cash Flows (Unaudited) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Cash Flows from Operating Activities:	'	'
Net income	$185	$147
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	235	240
Amortization of deferred financing costs	7	8
Deferred income taxes	4	57
Unrealized loss (gain) on marketable securities	30	-74
Equity in earnings of unconsolidated affiliates, net of distributions	-22	4
Pension contributions	-3	-8
Changes in other assets and liabilities:	'	'
Accounts receivable and unbilled revenues, net	-253	-66
Inventory	113	119
Taxes receivable	0	-3
Accounts payable	128	-33
Fuel cost recovery	-27	105
Non-trading derivatives, net	0	7
Margin deposits, net	1	12
Interest and taxes accrued	19	-76
Net regulatory assets and liabilities	27	39
Other current assets	20	8
Other current liabilities	-55	-32
Other assets	9	1
Other liabilities	13	15
Other, net	-8	12
Net cash provided by operating activities	380	533
Cash Flows from Investing Activities:	'	'
Capital expenditures	-301	-271
Decrease (increase) in restricted cash of transition and system restoration bond companies	-2	1
Other, net	-13	-4
Net cash used in investing activities	-316	-274
Cash Flows from Financing Activities:	'	'
Decrease in short-term borrowings, net	-43	-38
Proceeds from (payment of) commercial paper, net	-118	61
Proceeds from long-term debt	600	0
Payments of long-term debt	-231	-612
Cash paid for debt retirement	-1	0
Debt issuance costs	-5	0
Payment of common stock dividends	-102	-89
Proceeds from issuance of common stock, net	1	1
Other, net	6	17
Net cash provided by (used in) financing activities	107	-660
Net Increase (Decrease) in Cash and Cash Equivalents	171	-401
Cash and Cash Equivalents at Beginning of Period	208	646
Cash and Cash Equivalents at End of Period	379	245
Cash Payments:	'	'
Interest, net of capitalized interest	122	147
Income tax refunds, net	-1	-3
Non-cash transactions:	'	'
Accounts payable related to capital expenditures	59	92
Indexed Debt Securities, Unrealized Gain (Loss)	$43	($51)

Background_and_Basis_of_Presen

Background and Basis of Presentation	3 Months Ended
	Mar. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Background and Basis of Presentation	'
	Background and Basis of Presentation
	General. Included in this Quarterly Report on Form 10-Q (Form 10-Q) of CenterPoint Energy, Inc. are the condensed consolidated interim financial statements and notes (Interim Condensed Financial Statements) of CenterPoint Energy, Inc. and its subsidiaries (collectively, CenterPoint Energy). The Interim Condensed Financial Statements are unaudited, omit certain financial statement disclosures and should be read with the Annual Report on Form 10-K of CenterPoint Energy for the year ended December 31, 2013 (CenterPoint Energy Form 10-K).
	Background. CenterPoint Energy, Inc. is a public utility holding company. CenterPoint Energy’s operating subsidiaries own and operate electric transmission and distribution facilities and natural gas distribution facilities and own an interest in Enable Midstream Partners, LP (Enable) as described in Note 7. As of March 31, 2014, CenterPoint Energy’s indirect wholly owned subsidiaries included:
	•	CenterPoint Energy Houston Electric, LLC (CenterPoint Houston), which engages in the electric transmission and distribution business in the Texas Gulf Coast area that includes the city of Houston; and
	•	CenterPoint Energy Resources Corp. (CERC Corp. and, together with its subsidiaries, CERC), which owns and operates natural gas distribution systems (Gas Operations). A wholly owned subsidiary of CERC Corp. offers variable and fixed-price physical natural gas supplies primarily to commercial and industrial customers and electric and gas utilities. As of March 31, 2014, CERC Corp. also owned approximately 58.3% of the limited partner interests in Enable, which owns, operates and develops natural gas and crude oil infrastructure assets. Following the completion of Enable's initial public offering on April 16, 2014, CERC Corp. owns approximately 54.7% of the limited partner interests in Enable.
	As of March 31, 2014, CenterPoint Energy had four variable interest entities (VIEs) consisting of transition and system restoration bond companies, which it consolidates. The consolidated VIEs are wholly owned bankruptcy remote special purpose entities that were formed specifically for the purpose of securitizing transition and system restoration property. Creditors of CenterPoint Energy have no recourse to any assets or revenues of the transition and system restoration bond companies. The bonds issued by these VIEs are payable only from and secured by transition and system restoration property and the bondholders have no recourse to the general credit of CenterPoint Energy.
	Basis of Presentation. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
	CenterPoint Energy’s Interim Condensed Financial Statements reflect all normal recurring adjustments that are, in the opinion of management, necessary to present fairly the financial position, results of operations and cash flows for the respective periods. Amounts reported in CenterPoint Energy’s Condensed Statements of Consolidated Income are not necessarily indicative of amounts expected for a full-year period due to the effects of, among other things, (a) seasonal fluctuations in demand for energy and energy services, (b) changes in energy commodity prices, (c) timing of maintenance and other expenditures and (d) acquisitions and dispositions of businesses, assets and other interests.
	For a description of CenterPoint Energy’s reportable business segments, see Note 14.

New_Accounting_Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 31, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]	'
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	'
	New Accounting Pronouncements
	Management believes that recently issued standards, which are not yet effective, will not have a material impact on CenterPoint Energy’s consolidated financial position, results of operations or cash flows upon adoption.

Employee_Benefit_Plans

Employee Benefit Plans	3 Months Ended
	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]	'
Employee Benefit Plans	'
	Employee Benefit Plans
	CenterPoint Energy’s net periodic cost includes the following components relating to pension and postretirement benefits:
		Three Months Ended March 31,
		2014								2013
		Pension				Postretirement				Pension			Postretirement
		Benefits (1)				Benefits				Benefits (1)			Benefits
		(in millions)
	Service cost	$	10			$	—			$	11		$	—
	Interest cost	25				6				23			5
	Expected return on plan assets	(31		)		(2		)		(34		)	(2		)
	Amortization of prior service credit	3				—				2			—
	Amortization of net loss	11				—				16			2
	Amortization of transition obligation	—				1				—			2
	Net periodic cost	$	18			$	5			$	18		$	7
	________________
	-1	Net periodic cost in these tables is before considering amounts subject to overhead allocations for capital expenditure projects or for amounts subject to deferral for regulatory purposes.
	CenterPoint Energy's changes in accumulated comprehensive loss related to defined benefit and postretirement plans are as follows:
			Three Months Ended March 31,
			2014				2013
			Pension and Postretirement Plans
			(in millions)
	Beginning Balance		$	(88	)		$	(132	)
	Amounts reclassified from accumulated other comprehensive income:
	Prior service cost (1)		—				1
	Actuarial gains (1)		2				4
	Total reclassifications from accumulated other comprehensive income		2				5
	Tax expense		(1		)		(2		)
	Net current period other comprehensive income		1				3
	Ending Balance		$	(87	)		$	(129	)
	________________
	-1	These accumulated other comprehensive components are included in the computation of net periodic cost.
	CenterPoint Energy expects to contribute a total of approximately $96 million to its pension plans in 2014, of which approximately $3 million was contributed during the three months ended March 31, 2014. CenterPoint Energy contributed $29 million to the pension plans in April 2014.
	CenterPoint Energy expects to contribute a total of approximately $17 million to its postretirement benefits plan in 2014, of which approximately $4 million was contributed during the three months ended March 31, 2014.

Regulatory_Accounting

Regulatory Accounting	3 Months Ended
	Mar. 31, 2014
Regulatory Assets and Liabilities, Other Disclosures [Abstract]	'
Regulatory Matters	'
	Regulatory Accounting
	As of March 31, 2014, CenterPoint Energy has not recognized an allowed equity return of $493 million because such return will be recognized as it is recovered in rates. During the three months ended March 31, 2014 and 2013, CenterPoint Houston recognized approximately $15 million and $8 million, respectively, of the allowed equity return not previously recognized.

Derivative_Instruments

Derivative Instruments	3 Months Ended
	Mar. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments	'
	Derivative Instruments
	CenterPoint Energy is exposed to various market risks. These risks arise from transactions entered into in the normal course of business.  CenterPoint Energy utilizes derivative instruments such as physical forward contracts, swaps and options to mitigate the impact of changes in commodity prices and weather on its operating results and cash flows. Such derivatives are recognized in CenterPoint Energy’s Condensed Consolidated Balance Sheets at their fair value unless CenterPoint Energy elects the normal purchase and sales exemption for qualified physical transactions. A derivative may be designated as a normal purchase or sale if the intent is to physically receive or deliver the product for use or sale in the normal course of business.
	CenterPoint Energy has a Risk Oversight Committee composed of corporate and business segment officers that oversees all commodity price, weather and credit risk activities, including CenterPoint Energy’s marketing, risk management services and hedging activities. The committee’s duties are to establish CenterPoint Energy’s commodity risk policies, allocate board-approved commercial risk limits, approve the use of new products and commodities, monitor positions and ensure compliance with CenterPoint Energy’s risk management policies and procedures and limits established by CenterPoint Energy’s board of directors.
	CenterPoint Energy’s policies prohibit the use of leveraged financial instruments. A leveraged financial instrument, for this purpose, is a transaction involving a derivative whose financial impact will be based on an amount other than the notional amount or volume of the instrument.
	(a)	Non-Trading Activities
	Derivative Instruments. CenterPoint Energy enters into certain derivative instruments to manage physical commodity price risk and does not engage in proprietary or speculative commodity trading.  These financial instruments do not qualify or are not designated as cash flow or fair value hedges.
	Weather Hedges. CenterPoint Energy has weather normalization or other rate mechanisms that mitigate the impact of weather on its gas operations in Arkansas, Louisiana, Mississippi and Oklahoma. Gas operations in Texas and Minnesota and electric operations in Texas do not have such mechanisms. As a result, fluctuations from normal weather may have a significant positive or negative effect on Gas Operations’ results in these jurisdictions and on CenterPoint Houston’s results in its service territory.
	CenterPoint Energy entered into heating-degree day swaps for certain Gas Operations jurisdictions to mitigate the effect of fluctuations from normal weather on its results of operations and cash flows for the winter heating season, which contained a bilateral dollar cap of $15 million in 2012 - 2013 and $16 million in 2013 - 2014. In 2013, CenterPoint Energy also entered into a similar winter weather hedge for the CenterPoint Houston service territory, which contained a bilateral dollar cap of $7.5 million. The swaps are based on ten-year normal weather. During the three months ended March 31, 2014 and 2013, CenterPoint Energy recognized losses of $8 million and $3 million, respectively, related to these swaps. Weather hedge gains and losses are included in revenues in the Condensed Statements of Consolidated Income.
	(b)	Derivative Fair Values and Income Statement Impacts
	The following tables present information about CenterPoint Energy’s derivative instruments and hedging activities. The first four tables provide a balance sheet overview of CenterPoint Energy’s Derivative Assets and Liabilities as of March 31, 2014 and December 31, 2013, while the last table provides a breakdown of the related income statement impacts for the three months ended March 31, 2014 and 2013.
	Fair Value of Derivative Instruments
					March 31, 2014
	Total derivatives not designated		Balance Sheet		Derivative				Derivative
	as hedging instruments		Location		Assets				Liabilities
					Fair Value				Fair Value
					(in millions)
	Natural gas derivatives (1) (2)		Current Assets: Non-trading derivative assets		$	29			$	4
	Natural gas derivatives (1) (2)		Other Assets: Non-trading derivative assets		11				2
	Natural gas derivatives (1) (2)		Current Liabilities: Non-trading derivative liabilities		1				18
	Natural gas derivatives (1) (2)		Other Liabilities: Non-trading derivative liabilities		—				2
	Indexed debt securities derivative		Current Liabilities		—				412
	Total				$	41			$	438
	________________
	-1	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 547 billion cubic feet (Bcf) or a net 92 Bcf long position.  Of the net long position, basis swaps constitute 91 Bcf.
	-2	Natural gas contracts are presented on a net basis in the Condensed Consolidated Balance Sheets. Natural gas contracts are subject to master netting arrangements. This netting applies to all undisputed amounts due or past due and causes derivative assets (liabilities) to be ultimately presented net in a liability (asset) account within the Condensed Consolidated Balance Sheets. The net of total non-trading derivative assets and liabilities was a $14 million asset as shown on CenterPoint Energy’s Condensed Consolidated Balance Sheets (and as detailed in the table below), and was comprised of the natural gas contracts derivative assets and liabilities separately shown above, offset by collateral netting of $(1) million.
	Offsetting of Natural Gas Derivative Assets and Liabilities
			March 31, 2014
			Gross Amounts Recognized (1)				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amount Presented in the Consolidated Balance Sheets (2)
			(in millions)
	Current Assets: Non-trading derivative assets		$	30			$	(6	)		$	24
	Other Assets: Non-trading derivative assets		11				(2		)		9
	Current Liabilities: Non-trading derivative liabilities		(22		)		5				(17		)
	Other Liabilities: Non-trading derivative liabilities		(4		)		2				(2		)
	Total		$	15			$	(1	)		$	14
	________________
	-1	Gross amounts recognized include some derivative assets and liabilities that are not subject to master netting arrangements.
	-2	The derivative assets and liabilities on the Consolidated Balance Sheets exclude accounts receivable or accounts payable that, should they exist, could be used as offsets to these balances in the event of a default.
	Fair Value of Derivative Instruments
					December 31, 2013
	Total derivatives not designated		Balance Sheet		Derivative				Derivative
	as hedging instruments		Location		Assets				Liabilities
					Fair Value				Fair Value
					(in millions)
	Natural gas derivatives (1) (2) (3)		Current Assets: Non-trading derivative assets		$	28			$	4
	Natural gas derivatives (1) (2)		Other Assets: Non-trading derivative assets		10				—
	Natural gas derivatives (1) (2)		Current Liabilities: Non-trading derivative liabilities		4				21
	Natural gas derivatives (1) (2)		Other Liabilities: Non-trading derivative liabilities		1				5
	Indexed debt securities derivative		Current Liabilities		—				455
	Total				$	43			$	485
	________________
	-1	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 607 Bcf or a net 46 Bcf long position.  Of the net long position, basis swaps constitute 99 Bcf.
	-2	Natural gas contracts are presented on a net basis in the Condensed Consolidated Balance Sheets. Natural gas contracts are subject to master netting arrangements. This netting applies to all undisputed amounts due or past due and causes derivative assets (liabilities) to be ultimately presented net in a liability (asset) account within the Condensed Consolidated Balance Sheets. The net of total non-trading derivative assets and liabilities was a $13 million asset as shown on CenterPoint Energy’s Condensed Consolidated Balance Sheets (and as detailed in the table below), and was comprised of the natural gas contracts derivative assets and liabilities separately shown above, offset by collateral netting of less than $1 million.
	-3	The $28 million Derivative Current Asset includes $1 million related to physical forwards purchased from Enable.
	Offsetting of Natural Gas Derivative Assets and Liabilities
			December 31, 2013
			Gross Amounts Recognized (1)				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amount Presented in the Consolidated Balance Sheets (2)
			(in millions)
	Current Assets: Non-trading derivative assets		$	32			$	(8	)		$	24
	Other Assets: Non-trading derivative assets		11				(1		)		10
	Current Liabilities: Non-trading derivative liabilities		(25		)		8				(17		)
	Other Liabilities: Non-trading derivative liabilities		(5		)		1				(4		)
	Total		$	13			$	—			$	13
	________________
-1	Gross amounts recognized include some derivative assets and liabilities that are not subject to master netting arrangements.
-2	The derivative assets and liabilities on the Consolidated Balance Sheets exclude accounts receivable or accounts payable that, should they exist, could be used as offsets to these balances in the event of a default.
Realized and unrealized gains and losses on derivatives are recognized in the Condensed Statements of Consolidated Income as revenue for physical natural gas sales derivative contracts and as natural gas expense for financial natural gas derivatives and other physical natural gas derivatives. Unrealized gains and losses on indexed debt securities are recorded as Other Income (Expense) in the Condensed Statements of Consolidated Income.
Income Statement Impact of Derivative Activity
				Three Months Ended March 31,
Total derivatives not designated		Income Statement Location		2014				2013
as hedging instruments
				(in millions)
Natural gas derivatives		Gains (Losses) in Revenue		$	(101	)		$	(14	)
Natural gas derivatives (1)		Gains (Losses) in Expense: Natural Gas		110				16
Indexed debt securities derivative		Gains (Losses) in Other Income (Expense)		43				(51		)
Total				$	52			$	(49	)
________________
-1	The Gains (Losses) in Expense: Natural Gas includes $2 million during the three months ended March 31, 2014 related to physical forwards purchased from Enable.
(c)	Credit Risk Contingent Features
CenterPoint Energy enters into financial derivative contracts containing material adverse change provisions.  These provisions could require CenterPoint Energy to post additional collateral if the Standard & Poor’s Ratings Services or Moody’s Investors Service, Inc. credit ratings of CenterPoint Energy, Inc. or its subsidiaries are downgraded.  The total fair value of the derivative instruments that contain credit risk contingent features that are in a net liability position at both March 31, 2014 and December 31, 2013 was $1 million.  The aggregate fair value of assets that were posted as collateral was less than $1 million at both March 31, 2014 and December 31, 2013.  If all derivative contracts (in a net liability position) containing credit risk contingent features were triggered at March 31, 2014 and December 31, 2013, less than $1 million and $1 million, respectively, of additional assets would be required to be posted as collateral.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Disclosures [Text Block]	'
	Fair Value Measurements
	Assets and liabilities that are recorded at fair value in the Condensed Consolidated Balance Sheets are categorized based upon the level of judgment associated with the inputs used to measure their value. Hierarchical levels, as defined below and directly related to the amount of subjectivity associated with the inputs to fair valuations of these assets and liabilities, are as follows:
	Level 1: Inputs are unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date. The types of assets carried at Level 1 fair value generally are exchange-traded derivatives and equity securities.
	Level 2: Inputs, other than quoted prices included in Level 1, are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar instruments in active markets, and inputs other than quoted prices that are observable for the asset or liability. Fair value assets and liabilities that are generally included in this category are derivatives with fair values based on inputs from actively quoted markets.  A market approach is utilized to value CenterPoint Energy’s Level 2 assets or liabilities.
	Level 3: Inputs are unobservable for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. Unobservable inputs reflect CenterPoint Energy’s judgments about the assumptions market participants would use in pricing the asset or liability since limited market data exists. CenterPoint Energy develops these inputs based on the best information available, including CenterPoint Energy’s own data. A market approach is utilized to value CenterPoint Energy’s Level 3 assets or liabilities. Currently, CenterPoint Energy’s Level 3 assets and liabilities are comprised of physical forward contracts and options. Level 3 physical forward contracts are valued using a discounted cash flow model which includes illiquid forward price curve locations (ranging from $3.43 to $5.20 per one million British thermal units) as an unobservable input. Level 3 options are valued through Black-Scholes (including forward start) option models which include option volatilities (ranging from 0 to 62%) as an unobservable input.  CenterPoint Energy’s Level 3 derivative assets and liabilities consist of both long and short positions (forwards and options) and their fair value is sensitive to forward prices and volatilities. If forward prices decrease, CenterPoint Energy’s long forwards lose value whereas its short forwards gain in value.  If volatility decreases, CenterPoint Energy’s long options lose value whereas its short options gain in value.
	CenterPoint Energy determines the appropriate level for each financial asset and liability on a quarterly basis and recognizes transfers between levels at the end of the reporting period.  For the three months ended March 31, 2014, there were no transfers between Level 1 and 2. CenterPoint Energy also recognizes purchases of Level 3 financial assets and liabilities at their fair market value at the end of the reporting period.
	The following tables present information about CenterPoint Energy’s assets and liabilities (including derivatives that are presented net) measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013, and indicate the fair value hierarchy of the valuation techniques utilized by CenterPoint Energy to determine such fair value.
		Quoted Prices in			Significant Other			Significant		Netting			Balance
		Active Markets			Observable			Unobservable		Adjustments (1)			as of
		for Identical Assets			Inputs			Inputs					31-Mar-14
		(Level 1)			(Level 2)			(Level 3)
		(in millions)
	Assets
	Corporate equities	$	740		$	—		$	—	$	—		$	740
	Investments, including money	63			—			—		—			63
	market funds
	Natural gas derivatives	4			32			5		(8		)	33
	Total assets	$	807		$	32		$	5	$	(8	)	$	836
	Liabilities
	Indexed debt securities derivative	$	—		$	412		$	—	$	—		$	412
	Natural gas derivatives	1			20			5		(7		)	19
	Total liabilities	$	1		$	432		$	5	$	(7	)	$	431
	________________
	-1	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy to settle positive and negative positions and also include cash collateral of $(1) million posted with the same counterparties.
		Quoted Prices in			Significant Other			Significant		Netting			Balance
		Active Markets			Observable			Unobservable		Adjustments (1)			as of
		for Identical Assets			Inputs			Inputs					31-Dec-13
		(Level 1)			(Level 2)			(Level 3)
		(in millions)
	Assets
	Corporate equities	$	770		$	—		$	—	$	—		$	770
	Investments, including money	61			—			—		—			61
	market funds
	Natural gas derivatives (2)	5			33			5		(9		)	34
	Total assets	$	836		$	33		$	5	$	(9	)	$	865
	Liabilities
	Indexed debt securities derivative	$	—		$	455		$	—	$	—		$	455
	Natural gas derivatives	1			27			2		(9		)	21
	Total liabilities	$	1		$	482		$	2	$	(9	)	$	476
	________________
	-1	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy to settle positive and negative positions and also include cash collateral of less than $1 million posted with the same counterparties.
	-2	The (Level 2) Natural gas derivative assets of $33 million includes $1 million related to physical forwards purchased from Enable.
	The following table presents additional information about assets or liabilities, including derivatives that are measured at fair value on a recurring basis for which CenterPoint Energy has utilized Level 3 inputs to determine fair value:
		Fair Value Measurements Using Significant
		Unobservable Inputs (Level 3)
		Derivative assets and liabilities, net
		Three Months Ended March 31,
		2014			2013
		(in millions)
	Beginning balance	$	3		$	2
	Total gains (losses)	(2		)	2
	Total settlements	1			(1		)
	Transfers into Level 3	$	(1	)	$	—
	Ending balance (1)	$	1		$	3
	The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	$	(2	)	$	2
	________________
	-1	CenterPoint Energy did not have significant Level 3 purchases, sales or transfers out of Level 3 during the three months ended March 31, 2014 or 2013.
	Estimated Fair Value of Financial Instruments
	The fair values of cash and cash equivalents, investments in debt and equity securities classified as “trading” and short-term borrowings are estimated to be approximately equivalent to carrying amounts and have been excluded from the table below. The carrying amounts of non-trading derivative assets and liabilities and CenterPoint Energy’s 2.0% Zero-Premium Exchangeable Subordinated Notes due 2029 (ZENS) indexed debt securities derivative are stated at fair value and are excluded from the table below.  The fair value of each debt instrument is determined by multiplying the principal amount of each debt instrument by the market price. These assets and liabilities, which are not measured at fair value in the Condensed Consolidated Balance Sheets but for which the fair value is disclosed, would be classified as Level 1 or Level 2 in the fair value hierarchy.
		March 31, 2014						December 31, 2013
		Carrying			Fair			Carrying		Fair
		Amount			Value			Amount		Value
		(in millions)
Financial assets:
Notes receivable - affiliated companies	$	363		$	365		$	363	$	363
Financial liabilities:
Long-term debt	$	8,418		$	9,066		$	8,171	$	8,670

Unconsolidated_Affiliates_Note

Unconsolidated Affiliates (Notes)	3 Months Ended
	Mar. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]	'
Equity Method Investments and Joint Ventures Disclosure [Text Block]	'
	Unconsolidated Affiliates
	On May 1, 2013 (the Closing Date) CERC Corp., OGE Energy Corp. (OGE) and ArcLight Capital Partners, LLC (ArcLight) closed on the formation of Enable. CenterPoint Energy has the ability to significantly influence the operating and financial policies of Enable and, accordingly, accounts for its investment in Enable using the equity method of accounting. Under the equity method, CenterPoint Energy will adjust its investment in Enable each period for contributions made, distributions received, CenterPoint Energy’s share of Enable’s comprehensive income and accretion of any basis difference. CenterPoint Energy evaluates its equity method investments for impairment when events or changes in circumstances indicate there is a loss in value of the investment that is other than a temporary decline.
	CenterPoint Energy’s investment in Enable is considered to be a VIE because the power to direct the activities that most significantly impact Enable’s economic performance does not reside with the holders of equity investment at risk. However, CenterPoint Energy is not considered the primary beneficiary of Enable since it does not have the power to direct the activities of Enable that are considered most significant to the economic performance of Enable. CenterPoint Energy’s maximum exposure to loss related to Enable is limited to its equity investment as presented in the Condensed Consolidated Balance Sheet at March 31, 2014, CERC Corp.'s guarantee of Enable’s $1.05 billion term loan (Term Loan) and other guarantees discussed in Note 12, CERC Corp.’s $363 million notes receivable from Enable and outstanding current accounts receivable from Enable. CERC Corp.'s guarantee of Enable’s Term Loan is subordinated to all senior debt of CERC. The $363 million of notes receivable from Enable bears interest at an annual rate of 2.10% to 2.45% and mature in 2017. CenterPoint Energy had interest receivable of $6 million as of March 31, 2014 and interest income of $2 million during the three months ended March 31, 2014 on its $363 million of notes receivable from Enable.
	Effective on the Closing Date, CenterPoint Energy and Enable entered into a Services Agreement, Employee Transition Agreement, Transitional Services Agreement and other agreements (collectively, Transition Agreements) whereby CenterPoint Energy agreed to provide certain support services to Enable such as accounting, legal, risk management and treasury functions for an initial term ending on April 30, 2016. The support services automatically extend year-to-year at the end of the initial term, unless terminated by Enable with at least 90 days’ notice. Enable may terminate these support services at any time with 180 days’ notice if approved by the board of Enable's general partner.  Additionally, CenterPoint Energy agreed to provide seconded employees to Enable to support its operations for an initial term ending on December 31, 2014, unless revised by mutual agreement with CenterPoint Energy, OGE and Enable prior to that date.
	CenterPoint Energy did not transfer any employees to Enable at formation of the partnership or at any time during the period from the Closing Date to March 31, 2014. CenterPoint Energy billed Enable for reimbursement of transitional services, including the costs of seconded employees, of $45 million during the three months ended March 31, 2014, under the Transition Agreements. Actual transitional services costs are recorded net of reimbursements received from Enable. Effective April 1, 2014, Enable’s general partner, CenterPoint Energy and OGE agreed to reduce certain governance related costs billed to Enable for transition services.  These governance related costs were approximately $3 million in the three months ended March 31, 2014, which were included in the amounts billed for transitional services during the period. CenterPoint Energy had accounts receivable from Enable of $20 million as of March 31, 2014 for amounts billed for transitional services, including the cost of seconded employees.
	Enable, at its discretion, has the right to select and offer employment to seconded employees from CenterPoint Energy. As of March 31, 2014, CenterPoint Energy determined it cannot reasonably estimate the impact of the costs associated with the termination of employees related to the formation of Enable or transfer of employees from CenterPoint Energy to Enable, including the impact of the changes to the actuarial determination of employee benefit plan obligations. Pursuant to the Transition Agreements, Enable has agreed to reimburse CenterPoint Energy for severance and termination costs related to the termination of CenterPoint Energy's seconded employees, including any potential benefit-related costs, regardless of whether such seconded employees are offered employment by Enable.
	CERC has certain put rights, and Enable has certain call rights, exercisable with respect to the 25.05% interest in Southeast Supply Header, LLC (SESH) retained by CERC, under which CERC would contribute its retained interest in SESH, in exchange for a specified number of limited partner units in Enable and a cash payment, payable either from CERC to Enable or from Enable to CERC, for changes in the value of SESH. Specifically, the rights are exercisable with respect to a 24.95% interest in SESH (which may be exercised no earlier than May 2014) and a 0.1% interest in SESH (which may be exercised no earlier than May 2015). If CERC were to exercise its put rights or Enable were to exercise its call rights, CERC would contribute to Enable its 24.95% interest in SESH in exchange for 6,322,457 common units and its 0.1% interest in SESH in exchange for 25,341 common units. Subject to certain restrictions, if the fair market value of the contributed SESH interest is more or less than the value of the common units issued as consideration for the SESH interest, a cash payment may be required to be made by either Enable or CERC.
	During the three months ended March 31, 2014, CenterPoint Energy incurred natural gas expenses, including transportation and storage costs, of $47 million for transactions with Enable. CenterPoint Energy had accounts payable to Enable of $16 million at March 31, 2014 from such transactions.
	As of March 31, 2014, CenterPoint Energy held an approximate 58.3% limited partner interest in Enable and a 25.05% interest in SESH.
	On April 16, 2014, Enable completed its initial public offering of 28,750,000 common units at a price of $20.00 per unit, which included 3,750,000 common units sold by ArcLight pursuant to an over-allotment option that was fully exercised by the underwriters. Enable received approximately $466 million in net proceeds from the sale of the units, after deducting underwriting fees, structuring fees and other offering costs. Following the offering, CERC Corp. owns approximately 54.7% of the limited partner interests in Enable, which consists of 87,803,909 common units and 139,704,916 subordinated units.  Enable continues to be equally controlled by CenterPoint Energy and OGE; each own 50% of the management rights in the general partner of Enable. CenterPoint Energy and OGE also own a 40% and 60% interest, respectively, in the incentive distribution rights held by the general partner of Enable.
	Investment in Unconsolidated Affiliates:
			March 31,			December 31, 2013
			2014
			(in millions)
	Enable		$	4,340		$	4,319
	SESH		200			199
	Total		$	4,540		$	4,518
	Equity in Earnings of Unconsolidated Affiliates, net:
			Three Months Ended March 31,
			2014			2013
			(in millions)
	Enable		$	88		$	—
	SESH (1)		3			5
	Total		$	91		$	5
	-1	On May 1, 2013, CERC contributed a 24.95% interest in SESH to Enable, leaving CERC with a 25.05% interest in SESH.
	Summarized consolidated income information for Enable for the three months ended March 31, 2014 is as follows (in millions):
	Operating revenues		$	1,002
	Cost of sales, excluding depreciation and amortization		633
	Operating income		162
	Net income attributable to Enable		149
	CenterPoint Energy's approximate 58.3% interest		$	87
	Basis difference accretion gain		1
	CenterPoint Energy's approximate 58.3% interest, net		$	88
	Summarized consolidated balance sheet information for Enable as of March 31, 2014 is as follows (in millions):
	Current assets		$	500
	Non-current assets		10,758
	Current liabilities		1,039
	Non-current liabilities		2,002
	Non-controlling interest		34
	Enable partners' capital		8,183
	CenterPoint Energy's approximate 58.3% interest, net		$	4,773
	CenterPoint Energy's basis difference		(433		)
	CenterPoint Energy's investment in Enable		$	4,340
	Summarized basis difference information for Enable is as follows (in millions):
	Basis difference attributable to goodwill as of Closing Date (1)		$	229
	Basis difference to be accreted over 30 years as of Closing Date		210
	Total basis difference as of Closing Date		439
	Accumulated accretion of basis difference as of March 31, 2014		(6		)
	CenterPoint Energy's basis difference in Enable as of March 31, 2014		$	433
	-1	This difference related to CenterPoint Energy’s proportionate share of Enable’s goodwill arising from Enable's acquisition of Enogex, and therefore will not be recognized by CenterPoint Energy.
	Cash distributions received from Enable and SESH were approximately $67 million and $3 million, respectively, during the three months ended March 31, 2014 and were $-0- and $9 million, respectively, during the three months ended March 31, 2013.

Goodwill

Goodwill	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets Disclosure [Text Block]	'
	Goodwill
	Goodwill by reportable business segment as of both March 31, 2014 and December 31, 2013 is as follows (in millions):
	Natural Gas Distribution	$	746
	Energy Services	83
	Other Operations	11
	Total	$	840

Capital_Stock

Capital Stock	3 Months Ended
	Mar. 31, 2014
Class of Stock Disclosures [Abstract]	'
Capital Stock	'
	Capital Stock
	CenterPoint Energy, Inc. has 1,020,000,000 authorized shares of capital stock, comprised of 1,000,000,000 shares of $0.01 par value common stock and 20,000,000 shares of $0.01 par value preferred stock. At March 31, 2014, 429,748,633 shares of CenterPoint Energy, Inc. common stock were issued and 429,748,467 shares were outstanding. At December 31, 2013, 428,798,612 shares of CenterPoint Energy, Inc. common stock were issued and 428,798,446 shares were outstanding. Outstanding common shares exclude 166 treasury shares at both March 31, 2014 and December 31, 2013.

ShortTerm_Borrowings_and_Longt

Short-Term Borrowings and Long-term Debt	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
Short-term Borrowings and Long-term Debt [Text Block]	'
	Short-term Borrowings and Long-term Debt
	(a)	Short-term Borrowings
	Inventory Financing. Gas Operations has asset management agreements associated with its utility distribution service in Arkansas, north Louisiana and Oklahoma that extend through 2015. Pursuant to the provisions of the agreements, Gas Operations sells natural gas and agrees to repurchase an equivalent amount of natural gas during the winter heating seasons at the same cost, plus a financing charge. These transactions are accounted for as a financing and had an associated principal obligation of $-0- and $43 million as of March 31, 2014 and December 31, 2013, respectively.
	(b)	Long-term Debt
	On March 17, 2014, CenterPoint Energy Houston Electric, LLC issued $600 million principal amount of 4.50% General Mortgage Bonds due 2044.
	Debt Repayments. Approximately $44 million aggregate principal amount of pollution control bonds issued on behalf of CenterPoint Houston were redeemed on March 3, 2014 at 101% of their principal amount plus accrued interest. The bonds had an interest rate of 4.25%, were scheduled to mature in 2017 and were collateralized by general mortgage bonds of CenterPoint Houston.
	Approximately $56 million aggregate principal amount of pollution control bonds issued on behalf of CenterPoint Houston were purchased by CenterPoint Houston on March 3, 2014 at 101% of their principal amount plus accrued interest pursuant to the mandatory tender provisions of the bonds. The bonds had an interest rate of 5.60% prior to CenterPoint Houston's purchase and have a variable rate thereafter. The bonds mature in 2027 and are collateralized by general mortgage bonds of CenterPoint Houston. The purchased pollution control bonds may be remarketed.
	In April 2014, approximately $84 million aggregate principal amount of pollution control bonds issued on behalf of CenterPoint Houston were called for redemption on June 2, 2014 at 100% of their principal amount plus accrued interest. The bonds have an interest rate of 4.25%, mature in 2017 and are collateralized by general mortgage bonds of CenterPoint Houston.
	Credit Facilities. As of March 31, 2014 and December 31, 2013, CenterPoint Energy, CenterPoint Houston and CERC Corp. had the following revolving credit facilities and utilization of such facilities (in millions):
				March 31, 2014						December 31, 2013
		Size of		Loans		Letters		Commercial		Loans		Letters		Commercial
		Facility				of Credit		Paper				of Credit		Paper
	CenterPoint Energy	$	1,200	$	—	$	6	$	—	$	—	$	6	$	—
	CenterPoint Houston	300		—		4		—		—		4		—
	CERC Corp.	600		—		—		—		—		—		118
	Total	$	2,100	$	—	$	10	$	—	$	—	$	10	$	118
	CenterPoint Energy’s $1.2 billion revolving credit facility, which is scheduled to terminate on September 9, 2018, can be drawn at the London Interbank Offered Rate (LIBOR) plus 125 basis points based on CenterPoint Energy’s current credit ratings. The revolving credit facility contains a financial covenant which limits CenterPoint Energy’s consolidated debt (excluding transition and system restoration bonds) to an amount not to exceed 65% of CenterPoint Energy’s consolidated capitalization. The financial covenant limit will temporarily increase from 65% to 70% if CenterPoint Houston experiences damage from a natural disaster in its service territory and CenterPoint Energy certifies to the administrative agent that CenterPoint Houston has incurred system restoration costs reasonably likely to exceed $100 million in a consecutive twelve-month period, all or part of which CenterPoint Houston intends to seek to recover through securitization financing. Such temporary increase in the financial covenant would be in effect from the date CenterPoint Energy delivers its certification until the earliest to occur of (i) the completion of the securitization financing, (ii) the first anniversary of CenterPoint Energy’s certification or (iii) the revocation of such certification.
	CenterPoint Houston’s $300 million revolving credit facility, which is scheduled to terminate on September 9, 2018, can be drawn at LIBOR plus 112.5 basis points based on CenterPoint Houston’s current credit ratings. The revolving credit facility contains a financial covenant which limits CenterPoint Houston’s consolidated debt (excluding transition and system restoration bonds) to an amount not to exceed 65% of CenterPoint Houston's consolidated capitalization.
	CERC Corp.’s $600 million revolving credit facility, which is scheduled to terminate on September 9, 2018, can be drawn at LIBOR plus 150 basis points based on CERC Corp.’s current credit ratings. The revolving credit facility contains a financial covenant which limits CERC’s consolidated debt to an amount not to exceed 65% of CERC’s consolidated capitalization.
	CenterPoint Energy, CenterPoint Houston and CERC Corp. were in compliance with all financial covenants in their respective revolving credit facilities as of March 31, 2014.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	The effective tax rate reported for both the three months ended March 31, 2014 and March 31, 2013 was 37%. CenterPoint Energy reported no uncertain tax liability as of March 31, 2014 and expects no significant change to the uncertain tax liability for the twelve month period ending March 31, 2015. The consolidated federal income tax return filed for the year ended December 31, 2012 is currently under audit by the Internal Revenue Service.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	(a)	Natural Gas Supply Commitments
	Natural gas supply commitments include natural gas contracts related to CenterPoint Energy’s Natural Gas Distribution and Energy Services business segments, which have various quantity requirements and durations, that are not classified as non-trading derivative assets and liabilities in CenterPoint Energy’s Consolidated Balance Sheets as of March 31, 2014 and December 31, 2013 as these contracts meet an exception as “normal purchases contracts” or do not meet the definition of a derivative. Natural gas supply commitments also include natural gas transportation contracts that do not meet the definition of a derivative. As of March 31, 2014, minimum payment obligations for natural gas supply commitments are approximately $206 million for the remaining nine months in 2014, $363 million in 2015, $311 million in 2016, $247 million in 2017, $240 million in 2018 and $120 million after 2018.
	(b)	Legal, Environmental and Other Regulatory Matters
	Legal Matters
	Gas Market Manipulation Cases.  CenterPoint Energy, CenterPoint Houston or their predecessor, Reliant Energy, Incorporated (Reliant Energy), and certain of their former subsidiaries have been named as defendants in certain lawsuits described below. Under a master separation agreement between CenterPoint Energy and a former subsidiary, Reliant Resources, Inc. (RRI), CenterPoint Energy and its subsidiaries are entitled to be indemnified by RRI and its successors for any losses, including certain attorneys’ fees and other costs, arising out of these lawsuits.  In May 2009, RRI sold its Texas retail business to a subsidiary of NRG and RRI changed its name to RRI Energy, Inc. In December 2010, Mirant Corporation merged with and became a wholly owned subsidiary of RRI, and RRI changed its name to GenOn Energy, Inc. (GenOn). In December 2012, NRG acquired GenOn through a merger in which GenOn became a wholly owned subsidiary of NRG. None of the sale of the retail business, the merger with Mirant Corporation, or the acquisition of GenOn by NRG alters RRI’s (now GenOn’s) contractual obligations to indemnify CenterPoint Energy and its subsidiaries, including CenterPoint Houston, for certain liabilities, including their indemnification obligations regarding the gas market manipulation litigation, nor does it affect the terms of existing guarantee arrangements for certain GenOn gas transportation contracts discussed below.
	A large number of lawsuits were filed against numerous gas market participants in a number of federal and western state courts in connection with the operation of the natural gas markets in 2000-2002. CenterPoint Energy’s former affiliate, RRI, was a participant in gas trading in the California and Western markets. These lawsuits, many of which were filed as class actions, alleged violations of state and federal antitrust laws. Plaintiffs in these lawsuits sought a variety of forms of relief, including, among others, recovery of compensatory damages (in some cases in excess of $1 billion), a trebling of compensatory damages, full consideration damages and attorneys’ fees. CenterPoint Energy and/or Reliant Energy were named in approximately 30 of these lawsuits, which were instituted between 2003 and 2009. CenterPoint Energy and its affiliates have since been released or dismissed from all but one such case. CenterPoint Energy Services, Inc. (CES), a subsidiary of CERC Corp., is a defendant in a case now pending in federal court in Nevada alleging a conspiracy to inflate Wisconsin natural gas prices in 2000-2002.  In July 2011, the court issued an order dismissing the plaintiffs’ claims against other defendants in the case, each of whom had demonstrated FERC jurisdictional sales for resale during the relevant period, based on federal preemption.  The plaintiffs appealed this ruling to the United States Court of Appeals for the Ninth Circuit, which reversed the trial court's dismissal of the plaintiffs' claims. In August 2013, the other defendants filed a petition for review with the U.S. Supreme Court. CenterPoint Energy believes that CES is not a proper defendant in this case and will continue to pursue a dismissal.  CenterPoint Energy does not expect the ultimate outcome of this matter to have a material impact on its financial condition, results of operations or cash flows.
	Environmental Matters
	Manufactured Gas Plant Sites. CERC and its predecessors operated manufactured gas plants (MGPs) in the past. In Minnesota, CERC has completed remediation on two sites, other than ongoing monitoring and water treatment. There are five remaining sites in CERC’s Minnesota service territory. CERC believes that it has no liability with respect to two of these sites.
	At March 31, 2014, CERC had recorded a liability of $14 million for remediation of these Minnesota sites. The estimated range of possible remediation costs for the sites for which CERC believes it may have responsibility was $6 million to $41 million based on remediation continuing for 30 to 50 years. The cost estimates are based on studies of a site or industry average costs for remediation of sites of similar size. The actual remediation costs will be dependent upon the number of sites to be remediated, the participation of other potentially responsible parties (PRPs), if any, and the remediation methods used. The Minnesota Public Utilities Commission includes approximately $285,000 annually in rates to fund normal ongoing remediation costs.  As of March 31, 2014, CERC had collected $6.4 million from insurance companies to be used for future environmental remediation.
	In addition to the Minnesota sites, the United States Environmental Protection Agency and other regulators have investigated MGP sites that were owned or operated by CERC or may have been owned by one of its former affiliates. CERC and CenterPoint Energy do not expect the ultimate outcome of these investigations will have a material adverse impact on the financial condition, results of operations or cash flows of either CenterPoint Energy or CERC.
	Asbestos. Some facilities owned by CenterPoint Energy contain or have contained asbestos insulation and other asbestos-containing materials. CenterPoint Energy or its subsidiaries have been named, along with numerous others, as a defendant in lawsuits filed by a number of individuals who claim injury due to exposure to asbestos. Some of the claimants have worked at locations owned by subsidiaries of CenterPoint Energy, but most existing claims relate to facilities previously owned by CenterPoint Energy’s subsidiaries. CenterPoint Energy anticipates that additional claims like those received may be asserted in the future. In 2004 and early 2005, CenterPoint Energy sold its generating business, to which most of these claims relate, to a company which is now an affiliate of NRG. Under the terms of the arrangements regarding separation of the generating business from CenterPoint Energy and its sale of that business, ultimate financial responsibility for uninsured losses from claims relating to the generating business has been assumed by the NRG affiliate, but CenterPoint Energy has agreed to continue to defend such claims to the extent they are covered by insurance maintained by CenterPoint Energy, subject to reimbursement of the costs of such defense by the NRG affiliate. Although their ultimate outcome cannot be predicted at this time, CenterPoint Energy intends to continue vigorously contesting claims that it does not consider to have merit and, based on its experience to date, does not expect these matters, either individually or in the aggregate, to have a material adverse effect on CenterPoint Energy’s financial condition, results of operations or cash flows.
	Other Environmental. From time to time CenterPoint Energy identifies the presence of environmental contaminants on property where its subsidiaries conduct or have conducted operations.  Other such sites involving contaminants may be identified in the future.  CenterPoint Energy has and expects to continue to remediate identified sites consistent with its legal obligations. From time to time CenterPoint Energy has received notices from regulatory authorities or others regarding its status as a PRP in connection with sites found to require remediation due to the presence of environmental contaminants. In addition, CenterPoint Energy has been named from time to time as a defendant in litigation related to such sites. Although the ultimate outcome of such matters cannot be predicted at this time, CenterPoint Energy does not expect, based on its experience to date, these matters, either individually or in the aggregate, to have a material adverse effect on CenterPoint Energy’s financial condition, results of operations or cash flows.
	Other Proceedings
	CenterPoint Energy is involved in other legal, environmental, tax and regulatory proceedings before various courts, regulatory commissions and governmental agencies regarding matters arising in the ordinary course of business. From time to time, CenterPoint Energy is also a defendant in legal proceedings with respect to claims brought by various plaintiffs against broad groups of participants in the energy industry. Some of these proceedings involve substantial amounts. CenterPoint Energy regularly analyzes current information and, as necessary, provides accruals for probable liabilities on the eventual disposition of these matters. CenterPoint Energy does not expect the disposition of these matters to have a material adverse effect on CenterPoint Energy’s financial condition, results of operations or cash flows.
	(c)	Guarantees
	Prior to the distribution of CenterPoint Energy’s ownership in RRI to its shareholders, CERC had guaranteed certain contractual obligations of what became RRI’s trading subsidiary.  When the companies separated, RRI agreed to secure CERC against obligations under the guarantees RRI had been unable to extinguish by the time of separation.  Pursuant to such agreement, as amended in December 2007, RRI (now GenOn) agreed to provide to CERC cash or letters of credit as security against CERC’s obligations under its remaining guarantees for demand charges under certain gas transportation agreements if and to the extent changes in market conditions expose CERC to a risk of loss on those guarantees based on an annual calculation, with any required collateral to be posted each December.  The undiscounted maximum potential payout of the demand charges under these transportation contracts, which will be in effect until 2018, was approximately $55 million as of March 31, 2014.  Based on market conditions in the fourth quarter of 2013 at the time the most recent annual calculation was made under the agreement, GenOn was not obligated to post any security. If GenOn should fail to perform the contractual obligations, CERC could have to honor its guarantee and, in such event, any collateral then provided as security may be insufficient to satisfy CERC’s obligations.
	CenterPoint Energy has provided guarantees (CenterPoint Midstream Guarantees) with respect to the performance of certain obligations of Enable under long-term gas gathering and treating agreements with an indirect wholly owned subsidiary of Encana Corporation and an indirect wholly owned subsidiary of Royal Dutch Shell plc. As of March 31, 2014, CenterPoint Energy had guaranteed Enable's obligations up to an aggregate amount of $100 million under these agreements. Under the terms of the omnibus agreement entered into in connection with the closing of the formation of Enable, Enable and CenterPoint Energy have agreed to use commercially reasonable efforts and cooperate with each other to terminate the CenterPoint Midstream Guarantees and to release CenterPoint Energy from such guarantees by causing Enable or one of its subsidiaries to enter into substitute guarantees or to assume the CenterPoint Midstream Guarantees as applicable. CERC Corp. has also provided a guarantee of collection of Enable's obligations under its $1.05 billion three-year unsecured term loan facility, which guarantee is subordinated to all senior debt of CERC Corp.
	As of March 31, 2014, no amounts had been recorded in the Condensed Consolidated Balance Sheets related to these guarantees.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	The following table reconciles numerators and denominators of CenterPoint Energy’s basic and diluted earnings per share calculations:
		Three Months Ended March 31,
		2014		2013
		(in millions, except share and per share amounts)
	Net income	$	185	$	147
	Basic weighted average shares outstanding	429,163,000		427,961,000
	Plus: Incremental shares from assumed conversions:
	Stock options	—		100,000
	Restricted stock	1,396,000		1,611,000
	Diluted weighted average shares	430,559,000		429,672,000
	Basic earnings per share:
	Net income	$	0.43	$	0.34
	Diluted earnings per share:
	Net income	$	0.43	$	0.34

Reportable_Business_Segments

Reportable Business Segments	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Reportable Business Segments	'
	Reportable Business Segments
	CenterPoint Energy’s determination of reportable business segments considers the strategic operating units under which CenterPoint Energy manages sales, allocates resources and assesses performance of various products and services to wholesale or retail customers in differing regulatory environments. CenterPoint Energy uses operating income as the measure of profit or loss for its business segments.
	CenterPoint Energy’s reportable business segments include the following: Electric Transmission & Distribution, Natural Gas Distribution, Energy Services, Midstream Investments and Other Operations. The electric transmission and distribution function (CenterPoint Houston) is reported in the Electric Transmission & Distribution business segment. Natural Gas Distribution consists of intrastate natural gas sales to, and natural gas transportation and distribution for, residential, commercial, industrial and institutional customers. Energy Services represents CenterPoint Energy’s non-rate regulated gas sales and services operations. Midstream Investments consists primarily of CenterPoint Energy’s investment in Enable and its retained interest in SESH. Other Operations consists primarily of other corporate operations which support all of CenterPoint Energy’s business operations.
	Prior to May 1, 2013, CenterPoint Energy also reported an Interstate Pipelines business segment, which included CenterPoint Energy’s interstate natural gas pipeline operations, and a Field Services business segment, which included CenterPoint Energy’s non-rate regulated natural gas gathering, processing and treating operations. The formation of Enable closed on May 1, 2013. Enable now owns substantially all of CenterPoint Energy’s former Interstate Pipelines and Field Services business segments, except for the retained interest in SESH. As a result, effective May 1, 2013, CenterPoint Energy reports equity earnings associated with its interest in Enable and equity earnings associated with its retained interest in SESH under a new Midstream Investments segment, and no longer has Interstate Pipelines and Field Services reporting segments prospectively.
	Financial data for business segments is as follows (in millions):
		For the Three Months Ended March 31, 2014
		Revenues from			Net			Operating			Total Assets
		External			Intersegment			Income (Loss)			as of March 31,
		Customers			Revenues						2014
	Electric Transmission & Distribution	$	629	(1)	$	—		$	105		$	9,874
	Natural Gas Distribution	1,478			9			162			5,104
	Energy Services	1,052			32			26			1,053
	Midstream Investments (2)	—			—			—			4,540
	Other Operations	4			—			2			3,183			(3)
	Eliminations	—			(41		)	—			(1,490		)
	Consolidated	$	3,163		$	—		$	295		$	22,264
		For the Three Months Ended March 31, 2013
		Revenues from			Net			Operating			Total Assets
		External			Intersegment			Income (Loss)			as of December 31,
		Customers			Revenues						2013
	Electric Transmission & Distribution	$	532	(1)	$	—		$	84		$	9,605
	Natural Gas Distribution	1,043			8			139			4,976
	Energy Services	588			9			7			895
	Interstate Pipelines	92			40			52			—
	Field Services	130			11			53			—
	Midstream Investments (2)	—			—			—			4,518
	Other Operations	3			—			(3		)	3,026			(3)
	Eliminations	—			(68		)	—			(1,150		)
	Consolidated	$	2,388		$	—		$	332		$	21,870
	________________
	-1	Sales to affiliates of NRG in the three months ended March 31, 2014 and 2013 represented approximately $166 million and $144 million, respectively, of CenterPoint Houston’s transmission and distribution revenues.  Sales to affiliates of Energy Future Holdings Corp. in the three months ended March 31, 2014 and 2013 represented approximately $40 million and $36 million, respectively, of CenterPoint Houston’s transmission and distribution revenues.
	-2	Midstream Investments reported equity earnings of $88 million from Enable and $3 million of equity earnings from CenterPoint Energy’s retained interest in SESH for the three months ended March 31, 2014. Included in total assets of Midstream Investments as of March 31, 2014 and December 31, 2013 is $4,340 million and $4,319 million, respectively, related to CenterPoint Energy’s investment in Enable and $200 million and $199 million, respectively, related to CenterPoint Energy’s retained interest in SESH.
	-3	Included in total assets of Other Operations as of March 31, 2014 and December 31, 2013 are pension and other postemployment related regulatory assets of $616 million and $627 million, respectively.

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2014
Subsequent Events [Abstract]	'
Subsequent Events [Text Block]	'
	Subsequent Events
	On April 24, 2014, CenterPoint Energy’s board of directors declared a regular quarterly cash dividend of $0.2375 per share of common stock payable on June 10, 2014, to shareholders of record as of the close of business on May 16, 2014.

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]	'
Schedule of Defined Benefit Plans Disclosures [Table Text Block]	'
	CenterPoint Energy’s net periodic cost includes the following components relating to pension and postretirement benefits:
		Three Months Ended March 31,
		2014								2013
		Pension				Postretirement				Pension			Postretirement
		Benefits (1)				Benefits				Benefits (1)			Benefits
		(in millions)
	Service cost	$	10			$	—			$	11		$	—
	Interest cost	25				6				23			5
	Expected return on plan assets	(31		)		(2		)		(34		)	(2		)
	Amortization of prior service credit	3				—				2			—
	Amortization of net loss	11				—				16			2
	Amortization of transition obligation	—				1				—			2
	Net periodic cost	$	18			$	5			$	18		$	7
	________________
	-1	Net periodic cost in these tables is before considering amounts subject to overhead allocations for capital expenditure projects or for amounts subject to deferral for regulatory purposes.
	CenterPoint Energy's changes in accumulated comprehensive loss related to defined benefit and postretirement plans are as follows:
			Three Months Ended March 31,
			2014				2013
			Pension and Postretirement Plans
			(in millions)
	Beginning Balance		$	(88	)		$	(132	)
	Amounts reclassified from accumulated other comprehensive income:
	Prior service cost (1)		—				1
	Actuarial gains (1)		2				4
	Total reclassifications from accumulated other comprehensive income		2				5
	Tax expense		(1		)		(2		)
	Net current period other comprehensive income		1				3
	Ending Balance		$	(87	)		$	(129	)
	________________
	-1	These accumulated other comprehensive components are included in the computation of net periodic cost.

Derivative_Instruments_Tables

Derivative Instruments (Tables)	3 Months Ended
	Mar. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Fair Value of Derivative Instruments Table	'
	The following tables present information about CenterPoint Energy’s derivative instruments and hedging activities. The first four tables provide a balance sheet overview of CenterPoint Energy’s Derivative Assets and Liabilities as of March 31, 2014 and December 31, 2013, while the last table provides a breakdown of the related income statement impacts for the three months ended March 31, 2014 and 2013.
	Fair Value of Derivative Instruments
					March 31, 2014
	Total derivatives not designated		Balance Sheet		Derivative				Derivative
	as hedging instruments		Location		Assets				Liabilities
					Fair Value				Fair Value
					(in millions)
	Natural gas derivatives (1) (2)		Current Assets: Non-trading derivative assets		$	29			$	4
	Natural gas derivatives (1) (2)		Other Assets: Non-trading derivative assets		11				2
	Natural gas derivatives (1) (2)		Current Liabilities: Non-trading derivative liabilities		1				18
	Natural gas derivatives (1) (2)		Other Liabilities: Non-trading derivative liabilities		—				2
	Indexed debt securities derivative		Current Liabilities		—				412
	Total				$	41			$	438
	________________
	-1	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 547 billion cubic feet (Bcf) or a net 92 Bcf long position.  Of the net long position, basis swaps constitute 91 Bcf.
	-2	Natural gas contracts are presented on a net basis in the Condensed Consolidated Balance Sheets. Natural gas contracts are subject to master netting arrangements. This netting applies to all undisputed amounts due or past due and causes derivative assets (liabilities) to be ultimately presented net in a liability (asset) account within the Condensed Consolidated Balance Sheets. The net of total non-trading derivative assets and liabilities was a $14 million asset as shown on CenterPoint Energy’s Condensed Consolidated Balance Sheets (and as detailed in the table below), and was comprised of the natural gas contracts derivative assets and liabilities separately shown above, offset by collateral netting of $(1) million.
	Offsetting of Natural Gas Derivative Assets and Liabilities
			March 31, 2014
			Gross Amounts Recognized (1)				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amount Presented in the Consolidated Balance Sheets (2)
			(in millions)
	Current Assets: Non-trading derivative assets		$	30			$	(6	)		$	24
	Other Assets: Non-trading derivative assets		11				(2		)		9
	Current Liabilities: Non-trading derivative liabilities		(22		)		5				(17		)
	Other Liabilities: Non-trading derivative liabilities		(4		)		2				(2		)
	Total		$	15			$	(1	)		$	14
	________________
	-1	Gross amounts recognized include some derivative assets and liabilities that are not subject to master netting arrangements.
	-2	The derivative assets and liabilities on the Consolidated Balance Sheets exclude accounts receivable or accounts payable that, should they exist, could be used as offsets to these balances in the event of a default.
	Fair Value of Derivative Instruments
					December 31, 2013
	Total derivatives not designated		Balance Sheet		Derivative				Derivative
	as hedging instruments		Location		Assets				Liabilities
					Fair Value				Fair Value
					(in millions)
	Natural gas derivatives (1) (2) (3)		Current Assets: Non-trading derivative assets		$	28			$	4
	Natural gas derivatives (1) (2)		Other Assets: Non-trading derivative assets		10				—
	Natural gas derivatives (1) (2)		Current Liabilities: Non-trading derivative liabilities		4				21
	Natural gas derivatives (1) (2)		Other Liabilities: Non-trading derivative liabilities		1				5
	Indexed debt securities derivative		Current Liabilities		—				455
	Total				$	43			$	485
	________________
	-1	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 607 Bcf or a net 46 Bcf long position.  Of the net long position, basis swaps constitute 99 Bcf.
	-2	Natural gas contracts are presented on a net basis in the Condensed Consolidated Balance Sheets. Natural gas contracts are subject to master netting arrangements. This netting applies to all undisputed amounts due or past due and causes derivative assets (liabilities) to be ultimately presented net in a liability (asset) account within the Condensed Consolidated Balance Sheets. The net of total non-trading derivative assets and liabilities was a $13 million asset as shown on CenterPoint Energy’s Condensed Consolidated Balance Sheets (and as detailed in the table below), and was comprised of the natural gas contracts derivative assets and liabilities separately shown above, offset by collateral netting of less than $1 million.
	-3	The $28 million Derivative Current Asset includes $1 million related to physical forwards purchased from Enable.
	Offsetting of Natural Gas Derivative Assets and Liabilities
			December 31, 2013
			Gross Amounts Recognized (1)				Gross Amounts Offset in the Consolidated Balance Sheets				Net Amount Presented in the Consolidated Balance Sheets (2)
			(in millions)
	Current Assets: Non-trading derivative assets		$	32			$	(8	)		$	24
	Other Assets: Non-trading derivative assets		11				(1		)		10
	Current Liabilities: Non-trading derivative liabilities		(25		)		8				(17		)
	Other Liabilities: Non-trading derivative liabilities		(5		)		1				(4		)
	Total		$	13			$	—			$	13
	________________
	-1	Gross amounts recognized include some derivative assets and liabilities that are not subject to master netting arrangements.
	-2	The derivative assets and liabilities on the Consolidated Balance Sheets exclude accounts receivable or accounts payable that, should they exist, could be used as offsets to these balances in the event of a default.
Income Statement Impact of Derivative Activity Table	'
	Realized and unrealized gains and losses on derivatives are recognized in the Condensed Statements of Consolidated Income as revenue for physical natural gas sales derivative contracts and as natural gas expense for financial natural gas derivatives and other physical natural gas derivatives. Unrealized gains and losses on indexed debt securities are recorded as Other Income (Expense) in the Condensed Statements of Consolidated Income.
	Income Statement Impact of Derivative Activity
					Three Months Ended March 31,
	Total derivatives not designated		Income Statement Location		2014				2013
	as hedging instruments
					(in millions)
	Natural gas derivatives		Gains (Losses) in Revenue		$	(101	)		$	(14	)
	Natural gas derivatives (1)		Gains (Losses) in Expense: Natural Gas		110				16
	Indexed debt securities derivative		Gains (Losses) in Other Income (Expense)		43				(51		)
	Total				$	52			$	(49	)
	________________
	-1	The Gains (Losses) in Expense: Natural Gas includes $2 million during the three months ended March 31, 2014 related to physical forwards purchased from Enable.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair value, assets measured on a recurring basis	'
	The following tables present information about CenterPoint Energy’s assets and liabilities (including derivatives that are presented net) measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013, and indicate the fair value hierarchy of the valuation techniques utilized by CenterPoint Energy to determine such fair value.
		Quoted Prices in			Significant Other			Significant		Netting			Balance
		Active Markets			Observable			Unobservable		Adjustments (1)			as of
		for Identical Assets			Inputs			Inputs					31-Mar-14
		(Level 1)			(Level 2)			(Level 3)
		(in millions)
	Assets
	Corporate equities	$	740		$	—		$	—	$	—		$	740
	Investments, including money	63			—			—		—			63
	market funds
	Natural gas derivatives	4			32			5		(8		)	33
	Total assets	$	807		$	32		$	5	$	(8	)	$	836
	Liabilities
	Indexed debt securities derivative	$	—		$	412		$	—	$	—		$	412
	Natural gas derivatives	1			20			5		(7		)	19
	Total liabilities	$	1		$	432		$	5	$	(7	)	$	431
	________________
	-1	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy to settle positive and negative positions and also include cash collateral of $(1) million posted with the same counterparties.
		Quoted Prices in			Significant Other			Significant		Netting			Balance
		Active Markets			Observable			Unobservable		Adjustments (1)			as of
		for Identical Assets			Inputs			Inputs					31-Dec-13
		(Level 1)			(Level 2)			(Level 3)
		(in millions)
	Assets
	Corporate equities	$	770		$	—		$	—	$	—		$	770
	Investments, including money	61			—			—		—			61
	market funds
	Natural gas derivatives (2)	5			33			5		(9		)	34
	Total assets	$	836		$	33		$	5	$	(9	)	$	865
	Liabilities
	Indexed debt securities derivative	$	—		$	455		$	—	$	—		$	455
	Natural gas derivatives	1			27			2		(9		)	21
	Total liabilities	$	1		$	482		$	2	$	(9	)	$	476
	________________
	-1	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy to settle positive and negative positions and also include cash collateral of less than $1 million posted with the same counterparties.
	-2	The (Level 2) Natural gas derivative assets of $33 million includes $1 million related to physical forwards purchased from Enable.
Assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs	'
	The following table presents additional information about assets or liabilities, including derivatives that are measured at fair value on a recurring basis for which CenterPoint Energy has utilized Level 3 inputs to determine fair value:
		Fair Value Measurements Using Significant
		Unobservable Inputs (Level 3)
		Derivative assets and liabilities, net
		Three Months Ended March 31,
		2014			2013
		(in millions)
	Beginning balance	$	3		$	2
	Total gains (losses)	(2		)	2
	Total settlements	1			(1		)
	Transfers into Level 3	$	(1	)	$	—
	Ending balance (1)	$	1		$	3
	The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	$	(2	)	$	2
	________________
	-1	CenterPoint Energy did not have significant Level 3 purchases, sales or transfers out of Level 3 during the three months ended March 31, 2014 or 2013.
Estimated fair value of financial instruments, debt instruments	'
	The fair values of cash and cash equivalents, investments in debt and equity securities classified as “trading” and short-term borrowings are estimated to be approximately equivalent to carrying amounts and have been excluded from the table below. The carrying amounts of non-trading derivative assets and liabilities and CenterPoint Energy’s 2.0% Zero-Premium Exchangeable Subordinated Notes due 2029 (ZENS) indexed debt securities derivative are stated at fair value and are excluded from the table below.  The fair value of each debt instrument is determined by multiplying the principal amount of each debt instrument by the market price. These assets and liabilities, which are not measured at fair value in the Condensed Consolidated Balance Sheets but for which the fair value is disclosed, would be classified as Level 1 or Level 2 in the fair value hierarchy.
		March 31, 2014						December 31, 2013
		Carrying			Fair			Carrying		Fair
		Amount			Value			Amount		Value
		(in millions)
	Financial assets:
	Notes receivable - affiliated companies	$	363		$	365		$	363	$	363
	Financial liabilities:
	Long-term debt	$	8,418		$	9,066		$	8,171	$	8,670

Unconsolidated_Affiliates_Tabl

Unconsolidated Affiliates (Tables)	3 Months Ended
	Mar. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]	'
Summary of Investment Holdings, Schedule of Investments [Table Text Block]	'
			March 31,			December 31, 2013
			2014
			(in millions)
	Enable		$	4,340		$	4,319
	SESH		200			199
	Total		$	4,540		$	4,518
Schedule of Equity in Earning of Unconsolidated Affiliates [Table Text Block]	'
			Three Months Ended March 31,
			2014			2013
			(in millions)
	Enable		$	88		$	—
	SESH (1)		3			5
	Total		$	91		$	5
	-1	On May 1, 2013, CERC contributed a 24.95% interest in SESH to Enable, leaving CERC with a 25.05% interest in SESH.
	Summarized consolidated income information for Enable for the three months ended March 31, 2014 is as follows (in millions):
	Operating revenues		$	1,002
	Cost of sales, excluding depreciation and amortization		633
	Operating income		162
	Net income attributable to Enable		149
	CenterPoint Energy's approximate 58.3% interest		$	87
	Basis difference accretion gain		1
	CenterPoint Energy's approximate 58.3% interest, net		$	88
Schedule of Balance Sheet of Unconsolidated Affiliate [Table Text Block]	'
	Current assets		$	500
	Non-current assets		10,758
	Current liabilities		1,039
	Non-current liabilities		2,002
	Non-controlling interest		34
	Enable partners' capital		8,183
	CenterPoint Energy's approximate 58.3% interest, net		$	4,773
	CenterPoint Energy's basis difference		(433		)
	CenterPoint Energy's investment in Enable		$	4,340
Schedule of Basis Difference of Unconsolidated Affiliates [Table Text Block]	'
	Basis difference attributable to goodwill as of Closing Date (1)		$	229
	Basis difference to be accreted over 30 years as of Closing Date		210
	Total basis difference as of Closing Date		439
	Accumulated accretion of basis difference as of March 31, 2014		(6		)
	CenterPoint Energy's basis difference in Enable as of March 31, 2014		$	433

Goodwill_Tables

Goodwill (Tables)	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of Goodwill [Table Text Block]	'
	Goodwill by reportable business segment as of both March 31, 2014 and December 31, 2013 is as follows (in millions):
	Natural Gas Distribution	$	746
	Energy Services	83
	Other Operations	11
	Total	$	840

ShortTerm_Borrowings_and_Longt1

Short-Term Borrowings and Long-term Debt Credit Facilities (Tables)	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
Schedule of Line of Credit Facilities [Table Text Block]	'
	Credit Facilities. As of March 31, 2014 and December 31, 2013, CenterPoint Energy, CenterPoint Houston and CERC Corp. had the following revolving credit facilities and utilization of such facilities (in millions):
				March 31, 2014						December 31, 2013
		Size of		Loans		Letters		Commercial		Loans		Letters		Commercial
		Facility				of Credit		Paper				of Credit		Paper
	CenterPoint Energy	$	1,200	$	—	$	6	$	—	$	—	$	6	$	—
	CenterPoint Houston	300		—		4		—		—		4		—
	CERC Corp.	600		—		—		—		—		—		118
	Total	$	2,100	$	—	$	10	$	—	$	—	$	10	$	118

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	'
		Three Months Ended March 31,
		2014		2013
		(in millions, except share and per share amounts)
	Net income	$	185	$	147
	Basic weighted average shares outstanding	429,163,000		427,961,000
	Plus: Incremental shares from assumed conversions:
	Stock options	—		100,000
	Restricted stock	1,396,000		1,611,000
	Diluted weighted average shares	430,559,000		429,672,000
	Basic earnings per share:
	Net income	$	0.43	$	0.34
	Diluted earnings per share:
	Net income	$	0.43	$	0.34

Reportable_Business_Segments_T

Reportable Business Segments (Tables)	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Schedule of Segment Reporting Information, by Segment [Table Text Block]	'
	Financial data for business segments is as follows (in millions):
		For the Three Months Ended March 31, 2014
		Revenues from			Net			Operating			Total Assets
		External			Intersegment			Income (Loss)			as of March 31,
		Customers			Revenues						2014
	Electric Transmission & Distribution	$	629	(1)	$	—		$	105		$	9,874
	Natural Gas Distribution	1,478			9			162			5,104
	Energy Services	1,052			32			26			1,053
	Midstream Investments (2)	—			—			—			4,540
	Other Operations	4			—			2			3,183			(3)
	Eliminations	—			(41		)	—			(1,490		)
	Consolidated	$	3,163		$	—		$	295		$	22,264
		For the Three Months Ended March 31, 2013
		Revenues from			Net			Operating			Total Assets
		External			Intersegment			Income (Loss)			as of December 31,
		Customers			Revenues						2013
	Electric Transmission & Distribution	$	532	(1)	$	—		$	84		$	9,605
	Natural Gas Distribution	1,043			8			139			4,976
	Energy Services	588			9			7			895
	Interstate Pipelines	92			40			52			—
	Field Services	130			11			53			—
	Midstream Investments (2)	—			—			—			4,518
	Other Operations	3			—			(3		)	3,026			(3)
	Eliminations	—			(68		)	—			(1,150		)
	Consolidated	$	2,388		$	—		$	332		$	21,870
	________________
	-1	Sales to affiliates of NRG in the three months ended March 31, 2014 and 2013 represented approximately $166 million and $144 million, respectively, of CenterPoint Houston’s transmission and distribution revenues.  Sales to affiliates of Energy Future Holdings Corp. in the three months ended March 31, 2014 and 2013 represented approximately $40 million and $36 million, respectively, of CenterPoint Houston’s transmission and distribution revenues.
	-2	Midstream Investments reported equity earnings of $88 million from Enable and $3 million of equity earnings from CenterPoint Energy’s retained interest in SESH for the three months ended March 31, 2014. Included in total assets of Midstream Investments as of March 31, 2014 and December 31, 2013 is $4,340 million and $4,319 million, respectively, related to CenterPoint Energy’s investment in Enable and $200 million and $199 million, respectively, related to CenterPoint Energy’s retained interest in SESH.
	-3	Included in total assets of Other Operations as of March 31, 2014 and December 31, 2013 are pension and other postemployment related regulatory assets of $616 million and $627 million, respectively.

Background_and_Basis_of_Presen1

Background and Basis of Presentation (Details)	Mar. 31, 2014	Mar. 31, 2014	Apr. 16, 2014
		CERC Corp [Member]	Scenario, Forecast [Member]
		Midstream Partnership [Member]	CERC Corp [Member]
			Midstream Partnership [Member]
Equity Method Investment, Ownership Percentage	'	58.30%	54.70%
Number Of Vies Consolidated In Financial Statements	4	'	'

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)

3 Months Ended

1 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Apr. 30, 2014

Pension Plans, Defined Benefit [Member]

Pension Plans, Defined Benefit [Member]

Other Postretirement Benefit Plans, Defined Benefit [Member]

Other Postretirement Benefit Plans, Defined Benefit [Member]

Other Pension Plans, Postretirement or Supplemental Plans, Defined Benefit [Member]

Other Pension Plans, Postretirement or Supplemental Plans, Defined Benefit [Member]

Scenario, Forecast [Member]

Pension Plans, Defined Benefit [Member]

Defined Benefit Plan Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

Service cost

'

'

$10

[1]

$11

[1]

$0

$0

'

'

'

Interest cost

'

'

25

[1]

23

[1]

6

5

'

'

'

Expected return on plan assets

'

'

-31

[1]

-34

[1]

-2

-2

'

'

'

Amortization of prior service credit

'

'

3

[1]

2

[1]

0

0

'

'

'

Amortization of net loss

'

'

11

[1]

16

[1]

0

2

'

'

'

Amortization of transition obligation

'

'

0

[1]

0

[1]

1

2

'

'

'

Net periodic cost

'

'

18

[1]

18

[1]

5

7

'

'

'

Total contributions to the plans during the period

'

'

3

'

4

'

'

'

29

Total contributions expected in 2014

'

'

96

'

17

'

'

'

'

Defined Benefit Plan, Change in Accumulated Comprehensive Loss [Roll Forward]

'

'

'

'

'

'

'

'

'

Beginning Balance

-90

'

'

'

'

'

-88

-132

'

Amounts reclassified from accumulated other comprehensive income:

'

'

'

'

'

'

'

'

'

Prior service cost (1)

'

'

'

'

'

'

0

[2]

1

[2]

'

Actuarial gains (1)

'

'

'

'

'

'

2

[2]

4

[2]

'

Total reclassifications from accumulated other comprehensive income

'

'

'

'

'

'

2

5

'

Tax expense

'

'

'

'

'

'

-1

-2

'

Net current period other comprehensive income

1

3

'

'

'

'

1

3

'

Ending Balance

($89)

'

'

'

'

'

($87)

($129)

'

[1]

Net periodic cost in these tables is before considering amounts subject to overhead allocations for capital expenditure projects or for amounts subject to deferral for regulatory purposes.

[2]

These accumulated other comprehensive components are included in the computation of net periodic cost.

Regulatory_Accounting_Details

Regulatory Accounting (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Amount of allowed equity return on the true-up balance that has not been recognized	$493	'
Amount of allowed equity return on the true-up balance that was recognized in the period	$15	$8

Derivative_Instruments_Details

Derivative Instruments (Details) (USD $)	3 Months Ended				12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
	Years				MMcf
	MMcf
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	$41		'		$43
Derivative liabilities fair value	-438		'		-485
Derivative gross volumes on natural gas contracts (MMcf)	547,000		'		607,000
Net long position (MMcf)	92,000		'		46,000
Amount of net long position constituted by basis swaps (MMcf)	91,000		'		99,000
Net Amount Presented in the Consolidated Balance Sheets	14		'		13
Derivative, fair value, offsets, net	'		'		1
Cash Collateral Posted with Same Counterparties	-1		'		'
Total fair value of the derivative instruments that contain credit risk contingent features that are in a net liability position	1		'		1
The aggregate fair value of assets already posted as collateral	1		'		1
Credit Risk Contingent Features assets	1		'		1
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net [Abstract]	'		'		'
Term of normal weather used as the basis for weather hedges (in years)	10		'		'
Gains (Losses) Recognized Related to Weather Hedges	-8		-3		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	52		-49		'
Derivative Instruments, Assets, Physical Forwards Purchased	'		'		1
Natural gas derivatives [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Gross Amounts Recognized	15	[1]	'		13	[1]
Net Amount Presented in the Consolidated Balance Sheets	14	[2]	'		13	[2]
Derivative, fair value, offsets, net	'		'		0
Cash Collateral Posted with Same Counterparties	-1		'		'
Natural gas derivatives [Member] | Gains (Losses) in Revenue [Member]	'		'		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net [Abstract]	'		'		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	-101		-14		'
Natural gas derivatives [Member] | Gains (Losses) in Expense: Natural Gas [Member]	'		'		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net [Abstract]	'		'		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	110	[3]	16	[3]	'
Derivative Instruments physical purchase	2		'		'
Natural gas derivatives [Member] | Current Assets [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	30	[1]	'		32	[1]
Derivative Asset, Fair Value, Gross Liability	-6		'		-8
Net Amount Presented in the Consolidated Balance Sheets	24	[2]	'		24	[2]
Natural gas derivatives [Member] | Other Assets [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	11	[1]	'		11	[1]
Derivative Asset, Fair Value, Gross Liability	-2		'		-1
Net Amount Presented in the Consolidated Balance Sheets	9	[2]	'		10	[2]
Natural gas derivatives [Member] | Current Liabilities [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative liabilities fair value	-22	[1]	'		-25	[1]
Derivative Liability, Fair Value, Gross Asset	5		'		8
Net Amount Presented in the Consolidated Balance Sheets	-17	[2]	'		-17	[2]
Natural gas derivatives [Member] | Other Liabilities [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative liabilities fair value	-4	[1]	'		-5	[1]
Derivative Liability, Fair Value, Gross Asset	2		'		1
Net Amount Presented in the Consolidated Balance Sheets	-2	[2]	'		-4	[2]
Indexed Debt Securities Derivative [Member] | Gains (losses) in Other Income (Expense) [Member]	'		'		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net [Abstract]	'		'		'
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	43		-51		'
Not Designated as Hedging Instrument [Member] | Natural gas derivatives [Member] | Current Assets [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	29	[4],[5]	'		28	[6],[7],[8]
Derivative liabilities fair value	-4	[4],[5]	'		-4	[6],[7],[8]
Not Designated as Hedging Instrument [Member] | Natural gas derivatives [Member] | Other Assets [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	11	[4],[5]	'		10	[7],[8]
Derivative liabilities fair value	-2	[4],[5]	'		0	[7],[8]
Not Designated as Hedging Instrument [Member] | Natural gas derivatives [Member] | Current Liabilities [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	1	[4],[5]	'		4	[7],[8]
Derivative liabilities fair value	-18	[4],[5]	'		-21	[7],[8]
Not Designated as Hedging Instrument [Member] | Natural gas derivatives [Member] | Other Liabilities [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	0	[4],[5]	'		1	[7],[8]
Derivative liabilities fair value	-2	[4],[5]	'		-5	[7],[8]
Not Designated as Hedging Instrument [Member] | Indexed Debt Securities Derivative [Member] | Current Liabilities [Member]	'		'		'
Derivative, Fair Value, Net [Abstract]	'		'		'
Derivative assets fair value	0		'		0
Derivative liabilities fair value	-412		'		-455
CenterPoint Houston [Member]	'		'		'
Derivatives, Fair Value [Line Items]	'		'		'
Weather Hedge, Amount, maximum	7.5		'		'
2012 - 2013 [Member] | CERC Corp [Member]	'		'		'
Derivatives, Fair Value [Line Items]	'		'		'
Weather Hedge, Amount, maximum	15		'		'
2013 - 2014 [Member] | CERC Corp [Member]	'		'		'
Derivatives, Fair Value [Line Items]	'		'		'
Weather Hedge, Amount, maximum	$16		'		'
[1]	Gross amounts recognized include some derivative assets and liabilities that are not subject to master netting arrangements.
[2]	The derivative assets and liabilities on the Consolidated Balance Sheets exclude accounts receivable or accounts payable that, should they exist, could be used as offsets to these balances in the event of a default.
[3]	The Gains (Losses) in Expense: Natural Gas includes $2 million during the three months ended March 31, 2014 related to physical forwards purchased from Enable.
[4]	Natural gas contracts are presented on a net basis in the Condensed Consolidated Balance Sheets. Natural gas contracts are subject to master netting arrangements. This netting applies to all undisputed amounts due or past due and causes derivative assets (liabilities) to be ultimately presented net in a liability (asset) account within the Condensed Consolidated Balance Sheets. The net of total non-trading derivative assets and liabilities was a $14 million asset as shown on CenterPoint Energy’s Condensed Consolidated Balance Sheets (and as detailed in the table below), and was comprised of the natural gas contracts derivative assets and liabilities separately shown above, offset by collateral netting of $(1) million.
[5]	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 547 billion cubic feet (Bcf) or a net 92 Bcf long position. Of the net long position, basis swaps constitute 91 Bcf.
[6]	The $28 million Derivative Current Asset includes $1 million related to physical forwards purchased from Enable.
[7]	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 607 Bcf or a net 46 Bcf long position. Of the net long position, basis swaps constitute 99 Bcf.
[8]	Natural gas contracts are presented on a net basis in the Condensed Consolidated Balance Sheets. Natural gas contracts are subject to master netting arrangements. This netting applies to all undisputed amounts due or past due and causes derivative assets (liabilities) to be ultimately presented net in a liability (asset) account within the Condensed Consolidated Balance Sheets. The net of total non-trading derivative assets and liabilities was a $13 million asset as shown on CenterPoint Energy’s Condensed Consolidated Balance Sheets (and as detailed in the table below), and was comprised of the natural gas contracts derivative assets and liabilities separately shown above, offset by collateral netting of less than $1 million

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]	'		'		'
Cash Collateral Posted with Same Counterparties	($1)		'		'
Assets	'		'		'
Corporate equities	740		'		770
Investments, including money market funds	63		'		61
Natural gas derivatives, gross assets	41		'		43
Natural gas derivatives, assets	33		'		34	[1]
Total assets	836		'		865
Liabilities	'		'		'
Indexed debt securities derivative	412		'		455
Natural gas derivatives, gross liability	438		'		485
Natural gas derivatives, liabilities	19		'		21
Total liabilities	431		'		476
Cash collateral posted with counterparties	'		'		1
Derivative Instruments, Assets, Physical Forwards Purchased	'		'		1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'
Beginning balance	3		2		'
Total gains (losses)	-2		2		'
Total settlements	1		-1		'
Transfers into Level 3	-1		0		'
Ending balance (1)	1	[2]	3	[2]	'
The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at the reporting date	-2		2		'
Carrying Amount [Member]	'		'		'
Liabilities	'		'		'
Notes Receivable, Fair Value Disclosure	363		'		363
Long-term Debt	8,418		'		8,171
Fair Value [Member]	'		'		'
Liabilities	'		'		'
Notes Receivable, Fair Value Disclosure	365		'		363
Long-term Debt	9,066		'		8,670
Fair Value, Inputs, Level 1 [Member]	'		'		'
Assets	'		'		'
Corporate equities	740		'		770
Investments, including money market funds	63		'		61
Natural gas derivatives, gross assets	4		'		5	[1]
Total assets	807		'		836
Liabilities	'		'		'
Indexed debt securities derivative	0		'		0
Natural gas derivatives, gross liability	1		'		1
Total liabilities	1		'		1
Fair Value, Inputs, Level 2 [Member]	'		'		'
Assets	'		'		'
Corporate equities	0		'		0
Investments, including money market funds	0		'		0
Natural gas derivatives, gross assets	32		'		33	[1]
Total assets	32		'		33
Liabilities	'		'		'
Indexed debt securities derivative	412		'		455
Natural gas derivatives, gross liability	20		'		27
Total liabilities	432		'		482
Fair Value, Inputs, Level 3 [Member]	'		'		'
Assets	'		'		'
Corporate equities	0		'		0
Investments, including money market funds	0		'		0
Natural gas derivatives, gross assets	5		'		5	[1]
Total assets	5		'		5
Liabilities	'		'		'
Indexed debt securities derivative	0		'		0
Natural gas derivatives, gross liability	5		'		2
Total liabilities	5		'		2
Netting Adjustments [Member]	'		'		'
Assets	'		'		'
Corporate equities	0	[3]	'		0	[4]
Investments, including money market funds	0	[3]	'		0	[4]
Natural gas derivatives, netting adjustment	-8	[3]	'		-9	[1],[4]
Liabilities	'		'		'
Indexed debt securities derivative	0	[3]	'		0	[4]
Natural gas derivatives, netting adjustment	($7)	[3]	'		($9)	[4]
Minimum [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]	'		'		'
Option volatilities	0.00%		'		'
Maximum [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]	'		'		'
Option volatilities	62.00%		'		'
Forward Contracts [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]	'		'		'
Illiquid forward price per mmbtu	3.43		'		'
Forward Contracts [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]	'		'		'
Illiquid forward price per mmbtu	5.2		'		'
[1]	The (Level 2) Natural gas derivative assets of $33 million includes $1 million related to physical forwards purchased from Enable.
[2]	CenterPoint Energy did not have significant Level 3 purchases, sales or transfers out of Level 3 during the three months ended March 31, 2014 or 2013.
[3]	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy to settle positive and negative positions and also include cash collateral of $(1) million posted with the same counterparties.
[4]	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy to settle positive and negative positions and also include cash collateral of less than $1 million posted with the same counterparties.

Unconsolidated_Affiliates_Deta

Unconsolidated Affiliates (Details) (USD $)

3 Months Ended

3 Months Ended

1 Months Ended

1 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

1-May-13

Mar. 31, 2014

Mar. 31, 2014

Apr. 30, 2014

Apr. 16, 2014

Apr. 16, 2014

Apr. 30, 2014

Apr. 16, 2014

Apr. 16, 2014

SESH [Member]

SESH [Member]

Midstream Partnership [Member]

Midstream Partnership [Member]

OGE [Member]

OGE [Member]

CERC Corp [Member]

CERC Corp [Member]

Midstream Partnership [Member]

Midstream Partnership [Member]

SESH [Member]

SESH [Member]

SESH [Member]

May 2014 [Member]

may 2015 [Member]

Scenario, Forecast [Member]

Scenario, Forecast [Member]

Scenario, Forecast [Member]

Scenario, Forecast [Member]

Scenario, Forecast [Member]

Scenario, Forecast [Member]

Enable Midstream Partners [Member]

Midstream Partnership [Member]

Enable Midstream Partners [Member]

Midstream Partnership [Member]

SESH [Member]

SESH [Member]

Midstream Partnership [Member]

Midstream Partnership [Member]

CERC Corp [Member]

ArcLight [Member]

Common Stock [Member]

Subordinated Units [Member]

Midstream Partnership [Member]

Midstream Partnership [Member]

Midstream Partnership [Member]

Midstream Partnership [Member]

Guarantor Obligations, Current Amount

'

'

'

'

'

'

'

'

'

'

'

$1,050,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Indebtedness to CERC

363,000,000

'

363,000,000

'

'

'

'

'

'

'

'

363,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum

'

'

'

'

'

'

'

'

'

'

'

2.10%

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Interest Rate, Stated Percentage

'

'

'

'

'

'

'

'

'

'

'

2.45%

'

'

'

'

'

'

'

'

'

'

'

'

Interest Receivable

'

'

'

'

'

'

'

'

'

'

'

6,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Interest Income (Expense), Net

'

'

'

'

'

'

'

'

'

'

'

2,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Transitional Services Costs to be Reimbursed

45,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Transitional Service costs, eliminated

3,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Transitional Service cost receivable

20,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Ownership Percentage

'

'

'

'

'

'

'

'

'

'

58.30%

'

'

25.05%

'

'

'

'

'

'

54.70%

'

'

'

Equity Method Investment, Additional Contribution of Ownership Percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

24.95%

0.10%

'

'

'

'

'

'

Additional Paid in Capital, Common Stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

6,322,457

25,341

'

'

'

'

'

'

Cost of natural gas purchases, affiliates

47,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Due to Affiliate

16,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Partners' Capital Account, Public Sale of Units Net of Offering Costs

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

28,750,000

'

'

3,750,000

'

'

Sale of Stock, Price Per Share

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$20

'

'

'

'

Proceeds from Issuance Initial Public Offering

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

466,000,000

'

'

'

'

'

Investment in unconsolidated affiliates

4,540,000,000

'

4,518,000,000

'

'

'

'

'

'

'

'

4,340,000,000

4,319,000,000

200,000,000

199,000,000

'

'

'

'

'

'

'

'

'

Equity in earnings of unconsolidated affiliates, net

91,000,000

5,000,000

'

3,000,000

[1]

5,000,000

[1]

88,000,000

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Contributed Ownership Percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

24.95%

'

'

'

'

'

'

'

'

Operating Revenues

'

'

'

'

'

1,002,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Gross Margin

'

'

'

'

'

633,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Operating Income

'

'

'

'

'

162,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net Income

'

'

'

'

'

149,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

CenterPoint Energy's 58.3% interest

88,000,000

'

'

'

'

87,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Basis Difference Amortization

'

'

'

'

'

1,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Assets, Current

'

'

'

'

'

'

'

'

'

'

'

500,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Liabilities, Current

'

'

'

'

'

'

'

'

'

'

'

10,758,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Liabilities, Current

'

'

'

'

'

'

'

'

'

'

'

1,039,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Liabilities, Noncurrent

'

'

'

'

'

'

'

'

'

'

'

2,002,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Summarized Financial Information, Noncontrolling Interest

'

'

'

'

'

'

'

'

'

'

'

34,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment Summarized Financial Information, Equity

'

'

'

'

'

'

'

'

'

'

'

8,183,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Underlying Equity in Net Assets

4,773,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

equity method investment, basis difference, Total

-433,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Summarized Financial Information, Assets

4,340,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment_Basis Difference_Goodwill

229,000,000

[2]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment_Basis Difference To Be Accreted

210,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Basis Difference at Formation

439,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accumulated Gain (loss) basis difference

-6,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

equity method investment, basis difference, Total

433,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from Equity Method Investment, Dividends or Distributions

'

'

'

$3,000,000

$9,000,000

$67,000,000

$0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Ownership, Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

87,803,909

139,704,916

Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest

'

'

'

'

'

'

'

50.00%

'

50.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Incentive Distribution Right

'

'

'

'

'

'

'

'

60.00%

'

40.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

On May 1, 2013, CERC contributed a 24.95% interest in SESH to Enable, leaving CERC with a 25.05% interest in SESH.

[2]

This difference related to CenterPoint Energy’s proportionate share of Enable’s goodwill arising from Enable's acquisition of Enogex, and therefore will not be recognized by CenterPoint Energy.

Goodwill_Details

Goodwill (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Goodwill [Line Items]	'	'
Goodwill	$840	$840
Natural Gas Distribution [Member]	'	'
Goodwill [Line Items]	'	'
Goodwill	746	746
Energy Services [Member]	'	'
Goodwill [Line Items]	'	'
Goodwill	83	83
Corporate and Other [Member]	'	'
Goodwill [Line Items]	'	'
Goodwill	$11	$11

Capital_Stock_Details

Capital Stock (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Capital stock shares authorized (in shares)	1,020,000,000	'
Common stock shares authorized (in shares)	1,000,000,000	'
Common stock shares par value (in dollars per share)	$0.01	'
Cumulative preferred stock shares authorized (in shares)	20,000,000	'
Cumulative preferred stock par value (in dollars per share)	$0.01	'
Total common stock issued (in shares)	429,748,633	428,798,612
Total common stock outstanding (in shares)	429,748,467	428,798,446
Treasury stock (in shares)	166	166

ShortTerm_Borrowings_and_Longt2

Short-Term Borrowings and Long-term Debt (Details) (USD $)

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Apr. 30, 2014

In Millions, unless otherwise specified

Bank loans due 2016 [Member]

Bank loans due 2016 [Member]

Bank loans due 2016 [Member]

Bank loans due 2016 [Member]

Bank loans due 2016 [Member]

Bank loans due 2016 [Member]

March 2014 [Member]

March 2014 [Member]

Product Financing Arrangement [Member]

Product Financing Arrangement [Member]

Bonds General Mortgage Due 2044 [Member]

Scenario, Forecast [Member]

CenterPoint Houston [Member]

CenterPoint Houston [Member]

CenterPoint Energy [Member]

CenterPoint Energy [Member]

CERC Corp [Member]

CERC Corp [Member]

Bonds Pollution Control Due2017 [Member]

Bonds Pollution Control Due2027 [Member]

CenterPoint Houston [Member]

April 2014 [Member]

CenterPoint Houston [Member]

CenterPoint Houston [Member]

Bonds Pollution Control Due2017 [Member]

CenterPoint Houston [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Interest Rate, Stated Percentage

'

'

'

'

'

'

'

'

4.25%

5.60%

'

'

4.50%

4.25%

Debt Instrument, Maturity Date

'

'

'

'

'

'

'

'

31-Dec-17

31-Dec-27

'

'

31-Dec-44

31-Dec-17

Extinguishment Of Debt Purchase Price Percentage Of Principal

'

'

'

'

'

'

'

'

101.00%

101.00%

'

'

'

100.00%

Extinguishment of Debt, Amount

'

'

'

'

'

'

'

'

$44

$56

'

'

'

$84

Total short term borrowings

0

43

'

'

'

'

'

'

'

'

0

43

'

'

Debt Instrument, Face Amount

'

'

'

'

'

'

'

'

'

'

'

'

600

'

Long-term Debt [Abstract]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total credit facility amount

2,100

2,100

300

300

1,200

1,200

600

600

'

'

'

'

'

'

Loans Outstanding

0

0

0

0

0

0

0

0

'

'

'

'

'

'

Letters of Credit outstanding

10

10

4

4

6

6

0

0

'

'

'

'

'

'

Commercial Paper Outstanding

0

118

0

0

0

0

0

118

'

'

'

'

'

'

Revolving credit facility borrowing rate

'

'

'LIBOR plus 112.5

'

'London Interbank Offered Rate (LIBOR) plus 125

'

'LIBOR plus 150

'

'

'

'

'

'

'

Percentage on limitation of debt to total capitalization under covenant (in hundredths)

'

'

65.00%

'

65.00%

'

65.00%

'

'

'

'

'

'

'

Percentage on limitation of debt to total capitalization under covenant amended (in hundredths)

'

'

'

'

70.00%

'

'

'

'

'

'

'

'

'

System restoration costs threshold for increase in permitted debt to EBITDA covenant ratio

'

'

'

'

$100

'

'

'

'

'

'

'

'

'

Consecutive Period for System Restoration Costs to Exceed $100 million (in months)

'

'

'

'

12

'

'

'

'

'

'

'

'

'

Income_Taxes_Details

Income Taxes (Details)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Effective tax rate (in hundredths)	37.00%	37.00%

Commitments_and_Contingencies_

Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Mar. 31, 2014
Recorded Unconditional Purchase Obligation	'
Remainder of 2014	$206,000,000
2015	363,000,000
2016	311,000,000
2017	247,000,000
2018	240,000,000
After 2018	120,000,000
Legal Environmental And Other Regulatory Matters	'
Recovery of compensatory damages sought by plaintiffs	'in excess of $1 billion
Approximate number of gas market manipulation lawsuits naming CenterPoint and/or Reliant Energy (in number of lawsuits)	30
Number of gas market manipulation lawsuits pending for CenterPoint and its affiliates (in number of lawsuits)	1
Number of sites where remediation is complete, other than ongoing operations (in number of sites)	2
Number of remaining sites in the Minnesota service territory (in number of sites)	5
Number of the remaining sites in the Minnesota service territory where the company believes it has no liability (in number of sites)	2
Amount accrued for remediation of Minnesota sites (in number of sites)	14,000,000
Annual amount included in rates to fund normal on-going remediation costs	285,000
Amount collected from insurance companies to be used for future environmental remediation	6,400,000
Approximate amount of undiscounted maximum obligation under guarantee	55,000,000
CenterPoint Energy [Member]	'
Legal Environmental And Other Regulatory Matters	'
Guarantee Obligations Maximum Amount Upon Completion Of Gathering Systems	100,000,000
Midstream Partnership [Member]	'
Legal Environmental And Other Regulatory Matters	'
Guarantor Obligations, Current Amount	1,050,000,000
Minimum [Member]	'
Legal Environmental And Other Regulatory Matters	'
Maximum estimated remediation costs for the Minnesota sites	6,000,000
Years of remediation for the Minnesota sites (in years)	'30
Maximum [Member]	'
Legal Environmental And Other Regulatory Matters	'
Maximum estimated remediation costs for the Minnesota sites	$41,000,000
Years of remediation for the Minnesota sites (in years)	'50

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net income	$185	$147
Basic weighted average shares outstanding	429,163,000	427,961,000
Plus: Incremental shares from assumed conversions:	'	'
Stock Options	0	100,000
Restricted Stock	1,396,000	1,611,000
Diluted weighted average shares	430,559,000	429,672,000
Basic Earnings Per Share:	'	'
Net income	$0.43	$0.34
Diluted earnings per share:	'	'
Net income	$0.43	$0.34

Reportable_Business_Segments_D

Reportable Business Segments (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
Segment Reporting Information [Line Items]	'		'		'
Revenues	$3,163		$2,388		'
Operating Income (Loss)	295		332		'
Assets	22,264		'		21,870
Equity in earnings of unconsolidated affiliates, net	91		5		'
Investment in unconsolidated affiliates	4,540		'		4,518
Midstream Partnership [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Investment in unconsolidated affiliates	4,340		'		4,319
SESH [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Investment in unconsolidated affiliates	200		'		199
Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	-41		-68		'
Consolidation, Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Assets	-1,490		'		-1,150
Electric Transmission and Distribution [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	629	[1]	532	[1]	'
Operating Income (Loss)	105		84		'
Assets	9,874		'		9,605
Electric Transmission and Distribution [Member] | Affiliates of NRG Energy, Inc. [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	166		144		'
Electric Transmission and Distribution [Member] | Affiliates of Energy Future Holdings Corp. [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	40		36		'
Electric Transmission and Distribution [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	0		0		'
Natural Gas Distribution [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	1,478		1,043		'
Operating Income (Loss)	162		139		'
Assets	5,104		'		4,976
Natural Gas Distribution [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	-9		-8		'
Energy Services [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	1,052		588		'
Operating Income (Loss)	26		7		'
Assets	1,053		'		895
Energy Services [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	-32		-9		'
Interstate Pipelines [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	'		92		'
Operating Income (Loss)	'		52		'
Assets	'		'		0
Interstate Pipelines [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	'		-40		'
Field Services [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	'		130		'
Operating Income (Loss)	'		53		'
Assets	'		'		0
Field Services [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	'		-11		'
Midstream Investments [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	0	[2]	0	[2]	'
Operating Income (Loss)	0	[2]	0	[2]	'
Assets	4,540	[2]	'		4,518	[2]
Midstream Investments [Member] | Midstream Partnership [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Equity in earnings of unconsolidated affiliates, net	88		'		'
Investment in unconsolidated affiliates	4,340		'		4,319
Midstream Investments [Member] | CERC Remaining Interest in SESH [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Equity in earnings of unconsolidated affiliates, net	3		'		'
Midstream Investments [Member] | SESH [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Investment in unconsolidated affiliates	200		'		199
Midstream Investments [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	0	[2]	0	[2]	'
Other Operations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	4		3		'
Operating Income (Loss)	2		-3		'
Assets	3,183	[3]	'		3,026	[3]
Segment Reporting Pension Plan Assets	616		'		627
Other Operations [Member] | Intersegment Eliminations [Member]	'		'		'
Segment Reporting Information [Line Items]	'		'		'
Revenues	$0		$0		'
[1]	Sales to affiliates of NRG in the three months ended March 31, 2014 and 2013 represented approximately $166 million and $144 million, respectively, of CenterPoint Houston’s transmission and distribution revenues. Sales to affiliates of Energy Future Holdings Corp. in the three months ended March 31, 2014 and 2013 represented approximately $40 million and $36 million, respectively, of CenterPoint Houston’s transmission and distribution revenues.
[2]	Midstream Investments reported equity earnings of $88 million from Enable and $3 million of equity earnings from CenterPoint Energy’s retained interest in SESH for the three months ended March 31, 2014. Included in total assets of Midstream Investments as of March 31, 2014 and December 31, 2013 is $4,340 million and $4,319 million, respectively, related to CenterPoint Energy’s investment in Enable and $200 million and $199 million, respectively, related to CenterPoint Energy’s retained interest in SESH.
[3]	Included in total assets of Other Operations as of March 31, 2014 and December 31, 2013 are pension and other postemployment related regulatory assets of $616 million and $627 million, respectively.

Subsequent_Events_Details

Subsequent Events (Details) (Dividend Declared [Member], USD $)	3 Months Ended
	Mar. 31, 2014	Apr. 24, 2014
		Subsequent Event [Member]
Subsequent Event [Line Items]	'	'
Dividends Payable, Date Declared	24-Apr-14	'
Dividends Payable, Amount Per Share	'	$0.24
Dividends Payable, Date to be Paid, Day, Month and Year	10-Jun-14	'
Dividends Payable, Date of Record, Day, Month and Year	16-May-14	'