Document and Entity Information - USD ($)	6 Months Ended
Document and Entity Information - USD ($)	Jun. 30, 2018	Jul. 23, 2018	Jun. 30, 2017
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	Jun. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		431,553,691
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 11,722,467,012
Houston Electric [Member]
Entity Information [Line Items]
Entity Registrant Name	CENTERPOINT ENERGY HOUSTON ELECTRIC LLC
Entity Central Index Key	0000048732
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		1,000
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
CERC Corp [Member]
Entity Information [Line Items]
Entity Registrant Name	CENTERPOINT ENERGY RESOURCES CORP
Entity Central Index Key	0001042773
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		1,000
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes

CONDENSED STATEMENTS OF CONSOLIDATED INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues:
Utility revenues	$ 1,341	$ 1,222	$ 3,235	$ 2,768
Non-utility revenues	845	921	2,106	2,110
Total	2,186	2,143	5,341	4,878
Expenses:
Utility natural gas	188	150	825	600
Non-utility natural gas	790	882	2,063	2,011
Operation and maintenance	578	518	1,147	1,061
Depreciation and amortization	342	254	656	480
Taxes other than income taxes	101	99	212	195
Total	1,999	1,903	4,903	4,347
Operating Income	187	240	438	531
Other Income (Expense):
Gain on marketable securities	22	23	23	67
Loss on indexed debt securities	(254)	(13)	(272)	(23)
Interest and other finance charges	(91)	(77)	(169)	(155)
Interest on Securitization Bonds	(14)	(20)	(30)	(40)
Equity in earnings of unconsolidated affiliate, net	58	59	127	131
Other, net	4	(1)	7	(1)
Total	(275)	(29)	(314)	(21)
Income (Loss) Before Income Taxes	(88)	211	124	510
Income tax expense (benefit)	(13)	76	34	183
Net Income (Loss)	$ (75)	$ 135	$ 90	$ 327
Basic Earnings (Loss) Per Share	$ (0.17)	$ 0.31	$ 0.21	$ 0.76
Diluted Earnings (Loss) Per Share	(0.17)	0.31	0.21	0.75
Dividends Declared Per Share	$ 0.2775	$ 0.2675	$ 0.2775	$ 0.5350
Weighted Average Shares Outstanding, Basic	431,523,000	430,996,000	431,378,000	430,896,000
Weighted Average Shares Outstanding, Diluted	431,523,000	433,797,000	434,407,000	433,697,000
Houston Electric [Member]
Revenues:
Total	$ 854	$ 752	$ 1,609	$ 1,390
Expenses:
Operation and maintenance	351	343	693	684
Depreciation and amortization	262	180	495	332
Taxes other than income taxes	60	58	121	118
Total	673	581	1,309	1,134
Operating Income	181	171	300	256
Other Income (Expense):
Interest and other finance charges	(36)	(32)	(69)	(65)
Interest on Securitization Bonds	(14)	(20)	(30)	(40)
Other, net	(3)	(2)	(6)	(6)
Total	(53)	(54)	(105)	(111)
Income (Loss) Before Income Taxes	128	117	195	145
Income tax expense (benefit)	27	42	42	52
Net Income (Loss)	101	75	153	93
CERC Corp [Member]
Revenues:
Utility revenues	487	470	1,630	1,377
Non-utility revenues	841	917	2,098	2,103
Total	1,328	1,387	3,728	3,480
Expenses:
Utility natural gas	188	150	825	600
Non-utility natural gas	790	882	2,063	2,011
Operation and maintenance	217	190	455	405
Depreciation and amortization	72	68	145	134
Taxes other than income taxes	39	38	87	72
Total	1,306	1,328	3,575	3,222
Operating Income	22	59	153	258
Other Income (Expense):
Interest and other finance charges	(33)	(31)	(62)	(60)
Equity in earnings of unconsolidated affiliate, net	58	59	127	131
Other, net	(1)	(4)	(5)	(9)
Total	24	24	60	62
Income (Loss) Before Income Taxes	46	83	213	320
Income tax expense (benefit)	10	29	47	119
Net Income (Loss)	$ 36	$ 54	$ 166	$ 201

CONDENSED STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income (loss)	$ (75)	$ 135	$ 90	$ 327
Other comprehensive income:
Adjustment to pension and other postretirement plans (net of tax of $-0-, $1, $1 and $2)	2	1	3	2
Net deferred gain (loss) from cash flow hedges (net of tax of $-0-, $-0-, $1 and $-0-)	(1)	0	3	(1)
Total	1	1	6	1
Comprehensive income (loss)	(74)	136	96	328
Houston Electric [Member]
Net income (loss)	101	75	153	93
Other comprehensive income:
Net deferred gain (loss) from cash flow hedges (net of tax of $-0-, $-0-, $1 and $-0-)	0	0	4	(1)
Total	0	0	4	(1)
Comprehensive income (loss)	101	75	157	92
CERC Corp [Member]
Net income (loss)	36	54	166	201
Other comprehensive income:
Comprehensive income (loss)	$ 36	$ 54	$ 166	$ 201

CONDENSED STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Parentheticals) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Tax benefit (expense) on adjustment related to pension and postretirement plans	$ 0	$ (1)	$ (1)	$ (2)
Tax expense (benefit) on net deferred gain (loss) from cash flow hedges	0	0	1	0
Houston Electric [Member]
Tax expense (benefit) on net deferred gain (loss) from cash flow hedges	$ 0	$ 0	$ 1	$ 0

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 328	$ 260
Investment in marketable securities	584	960
Accounts receivable, less bad debt reserve	958	1,000
Accrued unbilled revenues	207	427
Natural gas inventory	152	222
Materials and supplies	192	175
Non-trading derivative assets	74	110
Taxes receivable	39	0
Prepaid expenses and other current assets	167	241
Total current assets	2,701	3,395
Property, Plant and Equipment:
Property, plant and equipment	19,585	19,031
Less: accumulated depreciation and amortization	6,188	5,974
Property, plant and equipment, net	13,397	13,057
Other Assets:
Goodwill	867	867
Regulatory assets	2,067	2,347
Non-trading derivative assets	46	44
Investment in unconsolidated affiliate	2,451	2,472
Preferred units – unconsolidated affiliate	363	363
Other	216	191
Total other assets	6,010	6,284
Total Assets	22,108	22,736
Current Liabilities:
Short-term borrowings	0	39
Current portion of VIE Securitization Bonds long-term debt	446	434
Indexed debt, net	26	122
Current portion of other long-term debt	50	50
Indexed debt securities derivative	641	668
Accounts payable	706	963
Taxes accrued	103	181
Interest accrued	118	104
Dividends accrued	0	120
Non-trading derivative liabilities	26	20
Due to ZENS note holders	382	0
Other	344	368
Total current liabilities	2,842	3,069
Other Liabilities:
Deferred income taxes, net	3,168	3,174
Non-trading derivative liabilities	12	4
Benefit obligations	723	785
Regulatory liabilities	2,521	2,464
Other	412	357
Total other liabilities	6,836	6,784
Long-term Debt:
VIE Securitization Bonds, net	1,193	1,434
Other long-term debt, net	6,567	6,761
Total long-term debt, net	7,760	8,195
Commitments and Contingencies (Note 14)
Shareholders’ Equity:
Cumulative preferred stock, $0.01 par value, 20,000,000 shares authorized, none issued or outstanding	0	0
Common stock	4	4
Additional paid-in capital	4,215	4,209
Retained earnings	513	543
Accumulated other comprehensive income (loss)	(62)	(68)
Total shareholders’ equity	4,670	4,688
Total Liabilities and Shareholders’ Equity	22,108	22,736
Houston Electric [Member]
Current Assets:
Cash and cash equivalents	253	238
Accounts and notes receivable	389	284
Accounts and notes receivable–affiliated companies	32	7
Accrued unbilled revenues	122	120
Materials and supplies	125	119
Taxes receivable	23	0
Prepaid expenses and other current assets	59	62
Total current assets	1,003	830
Property, Plant and Equipment:
Property, plant and equipment	11,812	11,496
Less: accumulated depreciation and amortization	3,741	3,633
Property, plant and equipment, net	8,071	7,863
Other Assets:
Regulatory assets	1,321	1,570
Other	35	29
Total other assets	1,356	1,599
Total Assets	10,430	10,292
Current Liabilities:
Current portion of VIE Securitization Bonds long-term debt	446	434
Accounts payable	208	243
Accounts and notes payable–affiliated companies	121	104
Taxes accrued	61	116
Interest accrued	75	65
Other	93	120
Total current liabilities	1,004	1,082
Other Liabilities:
Deferred income taxes, net	1,025	1,059
Benefit obligations	143	146
Regulatory liabilities	1,265	1,263
Other	56	54
Total other liabilities	2,489	2,522
Long-term Debt:
VIE Securitization Bonds, net	1,193	1,434
Other long-term debt, net	3,280	2,885
Total long-term debt, net	4,473	4,319
Commitments and Contingencies (Note 14)
Shareholders’ Equity:
Common stock	0	0
Additional paid-in capital	1,697	1,696
Retained earnings	763	673
Accumulated other comprehensive income (loss)	4	0
Total shareholders’ equity	2,464	2,369
Total Liabilities and Shareholders’ Equity	10,430	10,292
CERC Corp [Member]
Current Assets:
Cash and cash equivalents	1	12
Accounts receivable, less bad debt reserve	566	713
Accounts and notes receivable–affiliated companies	15	6
Accrued unbilled revenues	85	307
Natural gas inventory	152	222
Materials and supplies	67	56
Non-trading derivative assets	74	110
Prepaid expenses and other current assets	80	166
Total current assets	1,040	1,592
Property, Plant and Equipment:
Property, plant and equipment	7,104	6,888
Less: accumulated depreciation and amortization	2,136	2,036
Property, plant and equipment, net	4,968	4,852
Other Assets:
Goodwill	867	867
Regulatory assets	173	181
Non-trading derivative assets	46	44
Investment in unconsolidated affiliate	2,451	2,472
Other	97	104
Total other assets	3,634	3,668
Total Assets	9,642	10,112
Current Liabilities:
Short-term borrowings	0	39
Accounts payable	434	669
Accounts and notes payable–affiliated companies	36	611
Taxes accrued	48	75
Interest accrued	38	32
Customer deposits	75	76
Non-trading derivative liabilities	26	20
Other	152	137
Total current liabilities	809	1,659
Other Liabilities:
Deferred income taxes, net	1,330	1,289
Non-trading derivative liabilities	12	4
Benefit obligations	98	97
Regulatory liabilities	1,256	1,201
Other	352	297
Total other liabilities	3,048	2,888
Long-term Debt:
Total long-term debt, net	2,722	2,457
Commitments and Contingencies (Note 14)
Shareholders’ Equity:
Common stock	0	0
Additional paid-in capital	2,528	2,528
Retained earnings	529	574
Accumulated other comprehensive income (loss)	6	6
Total shareholders’ equity	3,063	3,108
Total Liabilities and Shareholders’ Equity	$ 9,642	$ 10,112

CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Cash and cash equivalents	$ 328	$ 260
Accounts receivable, less bad debt reserve	958	1,000
Bad debt reserve	21	19
Prepaid expenses and other current assets	167	241
Regulatory assets	$ 2,067	$ 2,347
Cumulative preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Cumulative preferred stock authorized (in shares)	20,000,000	20,000,000
Cumulative preferred stock outstanding (in shares)	0	0
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	1,000,000,000	1,000,000,000
Common stock outstanding (in shares)	431,547,782	431,044,845
Variable Interest Entity, Primary Beneficiary [Member]
Cash and cash equivalents	$ 253	$ 230
Accounts receivable, less bad debt reserve	112	73
Prepaid expenses and other current assets	37	35
Regulatory assets	1,293	1,590
Houston Electric [Member]
Cash and cash equivalents	253	238
Bad debt reserve	1	1
Prepaid expenses and other current assets	59	62
Regulatory assets	1,321	1,570
Houston Electric [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Cash and cash equivalents	253	230
Accounts receivable, less bad debt reserve	112	73
Prepaid expenses and other current assets	37	35
Regulatory assets	1,293	1,590
CERC Corp [Member]
Cash and cash equivalents	1	12
Accounts receivable, less bad debt reserve	566	713
Bad debt reserve	20	18
Prepaid expenses and other current assets	80	166
Regulatory assets	$ 173	$ 181

CONDENSED STATEMENTS OF CONSOLIDATED CASH FLOW (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash Flows from Operating Activities:
Net income	$ 90	$ 327
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	656	480
Amortization of deferred financing costs	18	12
Deferred income taxes	(12)	95
Unrealized gain on marketable securities	(23)	(67)
Loss on indexed debt securities	272	23
Write-down of natural gas inventory	1	0
Equity in earnings of unconsolidated affiliate, net of distributions	(9)	(131)
Pension contributions	(64)	(18)
Changes in other assets and liabilities, excluding acquisitions:
Accounts receivable and unbilled revenues, net	232	234
Inventory	52	(20)
Taxes receivable	(39)	30
Accounts payable	(246)	(158)
Fuel cost recovery	69	(12)
Non-trading derivatives, net	64	(49)
Margin deposits, net	(9)	(43)
Interest and taxes accrued	(64)	(17)
Net regulatory assets and liabilities	57	(34)
Other current assets	(4)	10
Other current liabilities	(13)	(29)
Other assets	(3)	(1)
Other liabilities	60	27
Other, net	8	18
Net cash provided by operating activities	1,093	677
Cash Flows from Investing Activities:
Capital expenditures	(697)	(649)
Acquisitions, net of cash acquired	0	(132)
Distributions from unconsolidated affiliate in excess of cumulative earnings	30	149
Proceeds from sale of marketable securities	398	0
Other, net	2	(8)
Net cash used in investing activities	(267)	(640)
Cash Flows from Financing Activities:
Decrease in short-term borrowings, net	(39)	(11)
Proceeds from (payments of) commercial paper, net	(1,188)	284
Proceeds from long-term debt, net	997	298
Payments of long-term debt	(230)	(469)
Debt issuance costs	(35)	(6)
Payment of dividends on common stock	(240)	(230)
Distribution to ZENS note holders	(16)	0
Other, net	(5)	(4)
Net cash provided by (used in) financing activities	(756)	(138)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	70	(101)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	296	381
Cash, Cash Equivalents and Restricted Cash at End of Period	366	280
Cash and Cash Equivalents at Beginning of Period	260
Cash and Cash Equivalents at End of Period	328
Houston Electric [Member]
Cash Flows from Operating Activities:
Net income	153	93
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	495	332
Amortization of deferred financing costs	6	6
Deferred income taxes	(38)	23
Changes in other assets and liabilities, excluding acquisitions:
Accounts receivable and unbilled revenues, net	(107)	(63)
Accounts receivable/payable–affiliated companies	78	(35)
Inventory	(6)	(1)
Taxes receivable	(23)	(38)
Accounts payable	(6)	57
Interest and taxes accrued	(45)	(41)
Net regulatory assets and liabilities	(59)	(59)
Other current assets	4	2
Other current liabilities	(11)	(7)
Other assets	2	4
Other liabilities	2	1
Other, net	(2)	5
Net cash provided by operating activities	443	279
Cash Flows from Investing Activities:
Capital expenditures	(441)	(414)
Decrease (increase) in notes receivable–affiliated companies	(26)	5
Other, net	(1)	(9)
Net cash used in investing activities	(468)	(418)
Cash Flows from Financing Activities:
Proceeds from long-term debt, net	398	298
Payments of long-term debt	(230)	(219)
Decrease in notes payable–affiliated companies	(60)	0
Dividend to parent	(63)	(42)
Debt issuance costs	(4)	(3)
Other, net	1	1
Net cash provided by (used in) financing activities	42	35
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	17	(104)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	274	381
Cash, Cash Equivalents and Restricted Cash at End of Period	291	277
Cash and Cash Equivalents at Beginning of Period	238
Cash and Cash Equivalents at End of Period	253
CERC Corp [Member]
Cash Flows from Operating Activities:
Net income	166	201
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	145	134
Amortization of deferred financing costs	4	4
Deferred income taxes	41	115
Write-down of natural gas inventory	1	0
Equity in earnings of unconsolidated affiliate, net of distributions	(9)	(131)
Changes in other assets and liabilities, excluding acquisitions:
Accounts receivable and unbilled revenues, net	339	295
Accounts receivable/payable–affiliated companies	(14)	(1)
Inventory	58	(18)
Accounts payable	(248)	(203)
Fuel cost recovery	69	(12)
Non-trading derivatives, net	61	(49)
Margin deposits, net	(9)	(43)
Interest and taxes accrued	(21)	(27)
Net regulatory assets and liabilities	92	(1)
Other current assets	7	12
Other current liabilities	8	(14)
Other assets	4	5
Other liabilities	52	10
Other, net	0	1
Net cash provided by operating activities	746	278
Cash Flows from Investing Activities:
Capital expenditures	(230)	(223)
Acquisitions, net of cash acquired	0	(132)
Distributions from unconsolidated affiliate in excess of cumulative earnings	30	149
Other, net	3	1
Net cash used in investing activities	(197)	(205)
Cash Flows from Financing Activities:
Decrease in short-term borrowings, net	(39)	(11)
Proceeds from (payments of) commercial paper, net	(333)	149
Proceeds from long-term debt, net	599	0
Decrease in notes payable–affiliated companies	(570)	0
Dividend to parent	(211)	(248)
Debt issuance costs	(5)	(1)
Contribution from parent	0	38
Other, net	(1)	0
Net cash provided by (used in) financing activities	(560)	(73)
Net Decrease in Cash and Cash Equivalents	(11)	0
Cash and Cash Equivalents at Beginning of Period	12	1
Cash and Cash Equivalents at End of Period	$ 1	$ 1

Background and Basis of Presentation

6 Months Ended

Jun. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Background and Basis of Presentation [Text Block]

Background and Basis of Presentation

No Registrant makes any representations as to the information related solely to CenterPoint Energy or the subsidiaries of CenterPoint Energy other than itself.

General. Included in this combined Form 10-Q are the Interim Condensed Financial Statements of CenterPoint Energy, Houston Electric and CERC, which are referred to collectively as the Registrants. The Combined Notes to the Unaudited Condensed Consolidated Financial Statements apply to all Registrants unless otherwise indicated. The Interim Condensed Financial Statements are unaudited, omit certain financial statement disclosures and should be read with each of the Registrants’ 2017 Form 10-K.

Background. CenterPoint Energy, Inc. is a public utility holding company. CenterPoint Energy’s operating subsidiaries, Houston Electric and CERC, own and operate electric transmission and distribution and natural gas distribution facilities, supply natural gas to commercial and industrial customers and electric and natural gas utilities and own interests in Enable as described below.


•	Houston Electric engages in the electric transmission and distribution business in the Texas Gulf Coast area that includes the city of Houston; and

•

CERC Corp. (i) owns and operates natural gas distribution systems in six states and (ii) obtains and offers competitive variable and fixed-price physical natural gas supplies and services primarily to commercial and industrial customers and electric and natural gas utilities in 33 states through its wholly-owned subsidiary, CES. As of June 30, 2018, CERC Corp. owned approximately 54.0% of the common units representing limited partner interests in Enable, which owns, operates and develops natural gas and crude oil infrastructure assets.

As of June 30, 2018, CenterPoint Energy also owned an aggregate of 14,520,000 Series A Preferred Units in Enable.

As of June 30, 2018, CenterPoint Energy and Houston Electric had VIEs consisting of the Bond Companies, which are consolidated. The consolidated VIEs are wholly-owned, bankruptcy-remote, special purpose entities that were formed specifically for the purpose of securitizing transition and system restoration-related property. Creditors of CenterPoint Energy and Houston Electric have no recourse to any assets or revenues of the 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 or Houston Electric.

Basis of Presentation. The preparation of financial statements in conformity with generally accepted accounting principles 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.

The 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 the 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. Certain prior year amounts have been reclassified to conform to the current year presentation.

For a description of the Registrants’ reportable business segments, see Note 16.

New Accounting Pronouncements

6 Months Ended

Jun. 30, 2018

New Accounting Pronouncements and Changes in Accounting Principles [Abstract]

New Accounting Pronouncements [Text Block]

New Accounting Pronouncements

The following table provides an overview of recently adopted or issued accounting pronouncements applicable to all the Registrants, unless otherwise noted.



Recently Adopted Accounting Standards
ASU Number and Name	Description	Date of Adoption	Financial Statement Impact upon Adoption
ASU 2014-09- Revenue from Contracts with Customers (Topic 606) and related amendments	This standard provides a comprehensive new revenue recognition model that requires revenue to be recognized in a manner that depicts the transfer of goods or services to a customer at an amount that reflects the consideration expected to be received in exchange for those goods or services. Transition method: modified retrospective	January 1, 2018	Note 4 addresses the disclosure requirements. Adoption of the standard did not result in significant changes to revenue recognition. A substantial amount of the Registrants’ revenues are tariff and/or derivative based, which were not significantly impacted by these ASUs.
ASU 2017-05- Other Income-Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets	This standard clarifies when and how to apply ASC 610-20, which was issued as part of ASU 2014-09. It amends or supersedes the guidance in ASC 350 and ASC 360 on determining a gain or loss recognized upon the derecognition of nonfinancial assets. Transition method: modified retrospective	January 1, 2018	ASU 2017-05 eliminates industry specific guidance, including ASC 360-20 Property, Plant, and Equipment - Real Estate Sales, for the recognition of gains or losses upon the sale of in-substance real estate. CenterPoint Energy and CERC elected to apply the practical expedient upon adoption to only evaluate transactions that were not determined to be complete as of the date of adoption. Subsequent to adoption, gains or losses on sales or dilution events in CenterPoint Energy’s or CERC’s investment in Enable may result in gains or losses recognized in earnings. See Note 9 for further discussion.
ASU 2016-01-Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities ASU 2018-03-Technical Corrections and Improvements to Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities	This standard requires equity investments that do not result in consolidation and are not accounted for under the equity method to be measured at fair value and to recognize any changes in fair value in net income unless the investments qualify for the new practicability exception. It does not change the guidance for classifying and measuring investments in debt securities and loans. It also changes certain disclosure requirements and other aspects related to recognition and measurement of financial assets and financial liabilities. Transition method: cumulative-effect adjustment to beginning retained earnings, and two features prospective	January 1, 2018	The adoption of this standard did not have an impact on the Registrants’ financial position, results of operations or cash flows. The Registrants elected the practicability exception for investments without a readily determinable fair value to be measured at cost. This includes the Series A Preferred Units in Enable, which were previously accounted for under the cost method. See Note 9 for further discussion.
ASU 2016-15- Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments	This standard provides clarifying guidance on the classification of certain cash receipts and payments in the statement of cash flows and eliminates the variation in practice related to such classifications. Transition method: retrospective	January 1, 2018	The adoption did not have a material impact on the Registrants’ financial position, results of operations or disclosures. However, CenterPoint Energy’s and Houston Electric’s Condensed Statements of Consolidated Cash Flows reflect an increase in investing activities and a corresponding decrease in operating activities of $1 million and $3 million for the six months ended June 30, 2018 and 2017, respectively, due to the requirement that cash proceeds from COLI policies be classified as cash inflows from investing activity.
ASU 2016-18- Statement of Cash Flows (Topic 230): Restricted Cash	This standard requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, restricted cash and restricted cash equivalents. As a result, the statement of cash flows will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents. When cash, cash equivalents, restricted cash and restricted cash equivalents are presented in more than one line item on the balance sheet, the new guidance requires a reconciliation of the totals in the statement of cash flows to the related captions in the balance sheet. Transition method: retrospective	January 1, 2018	The adoption of this standard did not have an impact on the Registrants’ financial position, results of operations or disclosures. However, CenterPoint Energy’s and Houston Electric’s Condensed Statements of Consolidated Cash Flows are reconciled to cash, cash equivalents and restricted cash, resulting in a decrease in investing activities of $2 million and an increase in investing activities of $8 million for the six months ended June 30, 2018 and 2017, respectively.



Recently Adopted Accounting Standards
ASU Number and Name	Description	Date of Adoption	Financial Statement Impact upon Adoption
ASU 2017-01- Business Combinations (Topic 805): Clarifying the Definition of a Business	This standard revises the definition of a business. If substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets, then under ASU 2017-01, the asset or group of assets is not a business. The guidance also requires a business to include at least one substantive process and narrows the definition of outputs to be more closely aligned with how outputs are described in ASC 606. Transition method: prospective	January 1, 2018	The adoption of this revised definition will reduce the number of transactions that are accounted for as a business combination, and therefore may have a potential impact on the Registrants’ accounting for future acquisitions.
ASU 2017-04- Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment	This standard eliminates Step 2 of the goodwill impairment test, which required a hypothetical purchase price allocation. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. Transition method: prospective	January 1, 2018	The adoption of this standard will have an impact on CenterPoint Energy’s and CERC’s future calculation of goodwill impairments if an impairment is identified.
ASU 2017-07- Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost	This standard requires an employer to report the service cost component of the net periodic pension cost and postretirement benefit cost in the same line item(s) as other employee compensation costs arising from services rendered during the period; all other components will be presented separately from the line item(s) that includes the service cost and outside of any subtotal of operating income. In addition, only the service cost component will be eligible for capitalization in assets. Transition method: retrospective for the presentation of the service cost component and other components; prospective for the capitalization of the service cost component	January 1, 2018	The adoption of this standard did not have a material impact on the Registrants’ financial position, results of operations, cash flows or disclosures; however, it resulted in the increases to operating income and corresponding decreases to other income reported in the table below. Other components previously capitalized in assets will be recorded as regulatory assets in the Registrants’ rate-regulated businesses, prospectively.
ASU 2017-09- Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting	This standard clarifies when changes to the terms or conditions of a share-based payment award must be accounted for as a modification. Entities will apply the modification accounting guidance if the value, vesting conditions or classification of the award changes. Transition method: prospective	January 1, 2018	The adoption of this standard will have an impact on CenterPoint Energy’s accounting for future changes to share-based payment awards.

The table below reflects the impact of adoption of ASU 2017-07:



	Three Months Ended June 30,
	2018						2017
	CenterPoint Energy		Houston Electric		CERC		CenterPoint Energy		Houston Electric		CERC
	(in millions)
Increase to operating income	$	15	$	8	$	4	$	17	$	7	$	6
Decrease to other income	15		8		4		17		7		6
	Six Months Ended June 30,
	2018						2017
	CenterPoint Energy		Houston Electric		CERC		CenterPoint Energy		Houston Electric		CERC
	(in millions)
Increase to operating income	$	29	$	15	$	8	$	34	$	15	$	11
Decrease to other income	29		15		8		34		15		11



Issued, Not Yet Effective Accounting Standards
ASU Number and Name	Description	Date of Adoption	Financial Statement Impact upon Adoption
ASU 2016-02- Leases (Topic 842) and related amendments ASU 2018-01- Leases (Topic 842) Land Easement Practical Expedient for Transition to Topic 842	ASU 2016-02 provides a comprehensive new lease model that requires lessees to recognize assets and liabilities for most leases and would change certain aspects of lessor accounting. Transition method: modified retrospective ASU 2018-01 allows entities to elect not to assess whether existing land easements that were not previously accounted for in accordance with ASC 840 Leases under ASC 842 Leases when transitioning to the new leasing standard.	January 1, 2019 Early adoption is permitted	The Registrants will elect the practical expedient on existing easements provided by ASU 2018-01 and are evaluating other available transitional practical expedients. The Registrants are in the process of reviewing contracts to identify leases as defined in ASU 2016-02 and expect to recognize on the statements of financial position right-of-use assets and lease liabilities for the majority of their respective leases that are currently classified as operating leases. The Registrants are continuing to assess the impact that adoption of these standards will have on their financial position, results of operations, cash flows and disclosures.
ASU 2017-12- Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities	This standard expands an entity’s ability to hedge nonfinancial and financial risk components and reduce complexity in fair value hedges of interest rate risk. The guidance eliminates the requirement to separately measure and report hedge ineffectiveness, eases certain documentation and assessment requirements and updates the presentation and disclosure requirements. Transition method: cumulative-effect adjustment for elimination of the separate measurement of ineffectiveness; prospective for presentation and disclosure	January 1, 2019 Early adoption is permitted	The Registrants are currently assessing the impact that adoption of this standard will have on their financial position, results of operations, cash flows and disclosures.
ASU 2018-02-Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income	This standard allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the TCJA and requires entities to provide certain disclosures regarding stranded tax effects. Transition method: either in the period of adoption or retrospective	January 1, 2019 Early adoption is permitted	The adoption of this standard will allow the Registrants to reclass stranded deferred tax adjustments primarily related to benefit plans from other comprehensive income to retained earnings. The Registrants are currently assessing the impact that adoption of this standard will have on their financial position and disclosures.

Management believes that other recently adopted standards and recently issued standards that are not yet effective will not have a material impact on the Registrants’ financial position, results of operations or cash flows upon adoption.

Proposed Merger with Vectren (CenterPoint Energy)	6 Months Ended
Proposed Merger with Vectren (CenterPoint Energy)	Jun. 30, 2018
Business Combinations [Abstract]
Proposed Merger with Vectren (CenterPoint Energy) [Text Block]	Proposed Merger with Vectren (CenterPoint Energy) On April 21, 2018, CenterPoint Energy entered into the Merger Agreement. Under the terms of the Merger Agreement, CenterPoint Energy will acquire Vectren for approximately $6 billion in cash. Upon closing, Vectren will become a wholly-owned subsidiary of CenterPoint Energy. Pursuant to the Merger Agreement, upon the closing of the Merger, each share of Vectren common stock issued and outstanding immediately prior to the closing will be converted automatically into the right to receive $72.00 in cash per share. CenterPoint Energy expects to finance the Merger with a combination of debt, equity-linked and equity issuances and has obtained commitments by lenders for a Bridge Facility to provide flexibility for the timing of the long-term acquisition financing and fund, in part, amounts payable by CenterPoint Energy in connection with the Merger. All outstanding debt held by Vectren and its subsidiaries will be assumed by CenterPoint Energy at the closing of the Merger. As of June 30, 2018, Vectren and its subsidiaries had outstanding $248 million of short-term debt and $2.0 billion of long-term debt, including current maturities. It is anticipated that Vectren and its subsidiaries will have approximately $2.5 billion of outstanding short-term and long-term debt as of December 31, 2018. Consummation of the Merger is conditioned upon approval by federal regulatory commissions, orders from state regulatory commissions, expiration or termination of the applicable HSR waiting period and approval of the Merger by Vectren shareholders. In June 2018, CenterPoint Energy and Vectren (i) submitted their filings with the FERC and the FCC and pursuant to the HSR Act and (ii) initiated informational proceedings with regulators in Indiana and Ohio. On June 26, 2018, CenterPoint Energy and Vectren received notice from the FTC granting early termination of the waiting period under the HSR Act in connection with the Merger. On July 16, 2018, Vectren filed its definitive proxy statement, as supplemented, with the SEC for a special meeting of its shareholders to be held on August 28, 2018 in connection with the Merger. The Merger Agreement contains termination rights for both CenterPoint Energy and Vectren, and provides that, upon termination of the Merger Agreement under specified circumstances, CenterPoint Energy would be required to pay a termination fee of $210 million to Vectren and Vectren would be required to pay CenterPoint Energy a termination fee of $150 million. Subject to receipt of required regulatory and statutory approvals and satisfaction and/or waiver of the closing conditions, CenterPoint Energy continues to anticipate closing the Merger in the first quarter of 2019.

Revenue Recognition

6 Months Ended

Jun. 30, 2018

Revenue from Contract with Customer [Abstract]

Revenue Recognition [Text Block]

Revenue Recognition

The Registrants adopted ASC 606 and all related amendments on January 1, 2018 using the modified retrospective method for those contracts that were not completed as of the date of adoption. Application of the new revenue standard did not result in a cumulative effect adjustment to the opening balance of retained earnings. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. The adoption of the new standard did not have a material impact on the Registrants’ financial position, results of operations or cash flows.

In accordance with ASC 606, revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration to which the Registrants expect to be entitled to receive in exchange for these goods or services. Contract assets and liabilities are not material.

The following tables disaggregate revenues by reportable business segment and major source:

CenterPoint Energy



	Three Months Ended June 30,
	2018														2017
	Electric Transmission & Distribution (1)			Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)		Total			Electric Transmission & Distribution (1)			Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)		Total
	(in millions)
Revenue from contracts	$	860		$	509		$	78		$	2	$	1,449		$	758		$	463		$	116		$	1	$	1,338
Derivatives income	—			—			782			—		782			—			—			815			—		815
Other (3)	(6		)	(14		)	—			2		(18		)	(6		)	14			—			2		10
Eliminations	—			(8		)	(19		)	—		(27		)	—			(7		)	(13		)	—		(20		)
Total revenues	$	854		$	487		$	841		$	4	$	2,186		$	752		$	470		$	918		$	3	$	2,143

	Six Months Ended June 30,
	2018														2017
	Electric Transmission & Distribution (1)			Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)		Total			Electric Transmission & Distribution (1)			Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)		Total
	(in millions)
Revenue from contracts	$	1,621		$	1,695		$	256		$	3	$	3,575		$	1,402		$	1,388		$	258		$	2	$	3,050
Derivatives income	(4		)	—			1,889			—		1,885			1			—			1,869			—		1,870
Other (3)	(12		)	(47		)	—			5		(54		)	(12		)	5			—			5		(2		)
Eliminations	—			(18		)	(47		)	—		(65		)	—			(16		)	(24		)	—		(40		)
Total revenues	$	1,605		$	1,630		$	2,098		$	8	$	5,341		$	1,391		$	1,377		$	2,103		$	7	$	4,878

Houston Electric



	Three Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
	(in millions)
Revenue from contracts	$	860		$	758		$	1,621		$	1,402
Other (3)	(6		)	(6		)	(12		)	(12		)
	$	854		$	752		$	1,609		$	1,390

CERC



	Three Months Ended June 30,
	2018											2017
	Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)		Total			Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)			Total
	(in millions)
Revenue from contracts	$	509		$	78		$	—	$	587		$	463		$	116		$	—		$	579
Derivatives income	—			782			—		782			—			815			—			815
Other (3)	(14		)	—			—		(14		)	14			—			(1		)	13
Eliminations	(8		)	(19		)	—		(27		)	(7		)	(13		)	—			(20		)
Total revenues	$	487		$	841		$	—	$	1,328		$	470		$	918		$	(1	)	$	1,387

	Six Months Ended June 30,
	2018											2017
	Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)		Total			Natural Gas Distribution (1)			Energy Services (2)			Other Operations (2)			Total
	(in millions)
Revenue from contracts	$	1,695		$	256		$	—	$	1,951		$	1,388		$	258		$	—		$	1,646
Derivatives income	—			1,889			—		1,889			—			1,869			—			1,869
Other (3)	(47		)	—			—		(47		)	5			—			—			5
Eliminations	(18		)	(47		)	—		(65		)	(16		)	(24		)	—			(40		)
Total revenues	$	1,630		$	2,098		$	—	$	3,728		$	1,377		$	2,103		$	—		$	3,480


(1)	Reflected in Utility revenues in the Condensed Statements of Consolidated Income.


(2)	Reflected in Non-utility revenues in the Condensed Statements of Consolidated Income.

(3)

Primarily consists of income from ARPs and leases. ARPs are contracts between the utility and its regulators, not between the utility and a customer. The Registrants recognize ARP revenue as other revenues when the regulator-specified conditions for recognition have been met. Upon recovery of ARP revenue through incorporation in rates charged for utility service to customers, ARP revenue is reversed and recorded as revenue from contracts with customers. The recognition of ARP revenues and the reversal of ARP revenues upon recovery through rates charged for utility service may not occur in the same period.

Revenues from Contracts with Customers

Electric Transmission & Distribution. Houston Electric distributes electricity to customers over time and customers consume the electricity when delivered. Revenue, consisting of both volumetric and fixed tariff rates set by the PUCT, is recognized as electricity is delivered and represents amounts both billed and unbilled. Discretionary services requested by customers are provided at a point in time with control transferring upon the completion of the service. Revenue for discretionary services is recognized upon completion of service based on the tariff rates set by the PUCT. Payments for electricity distribution and discretionary services are aggregated and received on a monthly basis. Houston Electric performs transmission services over time as a stand-ready obligation to provide a reliable network of transmission systems. Revenue is recognized upon time elapsed, and the monthly tariff rate set by the PUCT. Payments are received on a monthly basis.

Natural Gas Distribution. CERC distributes and transports natural gas to customers over time, and customers consume the natural gas when delivered. Revenue, consisting of both volumetric and fixed tariff rates set by the state governing agency for that service area, is recognized as natural gas is delivered and represents amounts both billed and unbilled. Discretionary services requested by the customer are satisfied at a point in time and revenue is recognized upon completion of service and the tariff rates set by the applicable state regulator. Payments of natural gas distribution, transportation and discretionary services are aggregated and received on a monthly basis.

Energy Services. The majority of CES natural gas sales contracts are considered a derivative, as the contracts typically have a stated minimum or contractual volume of delivery.

For contracts in which CES delivers the full requirement of the natural gas needed by the customer and a volume is not stated, a contract as defined under ASC 606 is created upon the customer’s exercise of its option to take natural gas. CES supplies natural gas to retail customers over time as customers consume the natural gas when delivered. For wholesale customers, CES supplies natural gas at a point in time because the wholesale customer is presumed to have storage capabilities. Control is transferred to both types of customers upon delivery of natural gas. Revenue is recognized on a monthly basis based on the estimated volume of natural gas delivered and the price agreed upon with the customer. Payments are received on a monthly basis.

AMAs are natural gas sales contracts under which CES also assumes management of a customer’s physical storage and/or transportation capacity. AMAs have two distinct performance obligations, which consist of natural gas sales and natural gas delivery because delivery could occur separate from the sale of natural gas (e.g., from storage to customer premises). Most AMAs’ natural gas sales performance obligations are accounted for as embedded derivatives. The transaction price is allocated between the sale of natural gas and the delivery based on the stand-alone selling price as stated in the contract. CES performs natural gas delivery over time as customers take delivery of the natural gas and recognizes revenue on an aggregated monthly basis based on the volume of natural gas delivered and the fees stated within the contract. Payments are received on a monthly basis.

Practical Expedients and Exemption. Sales taxes and other similar taxes collected from customers are excluded from the transaction price.