CenterPoint Energy (CNP) 10-Q 7 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Jul. 26, 2019
Entity Information [Line Items]
Entity Incorporation, State or Country Code	TX
Entity Shell Company	false
Entity Interactive Data Current	Yes
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, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		502,218,696
Entity Current Reporting Status	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	1-31447
Entity Tax Identification Number	74-0694415
Entity Address, Address Line One	1111 Louisiana
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77002
City Area Code	713
Local Phone Number	207-1111
Houston Electric [Member]
Entity Information [Line Items]
Entity Incorporation, State or Country Code	TX
Entity Shell Company	false
Entity Interactive Data Current	Yes
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, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		1,000
Entity Current Reporting Status	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Tax Identification Number	22-3865106
Entity Address, Address Line One	1111 Louisiana
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77002
City Area Code	713
Local Phone Number	207-1111
CERC Corp [Member]
Entity Information [Line Items]
Entity Incorporation, State or Country Code	DE
Entity Shell Company	false
Entity Interactive Data Current	Yes
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, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		1,000
Entity Current Reporting Status	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Tax Identification Number	76-0511406
Entity Address, Address Line One	1111 Louisiana
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77002
City Area Code	713
Local Phone Number	207-1111
Common Stock, $0.01 Par Value [Member] | New York Stock Exchange [Member]
Entity Information [Line Items]
Trading Symbol	CNP
Title of 12(b) Security	Common Stock, $0.01 par value
Security Exchange Name	NYSE
Common Stock, $0.01 Par Value [Member] | Chicago Stock Exchange [Member]
Entity Information [Line Items]
Trading Symbol	CNP
Title of 12(b) Security	Common Stock, $0.01 par value
Security Exchange Name	CHX
Depositary Shares [Member] | New York Stock Exchange [Member]
Entity Information [Line Items]
Trading Symbol	CNP/PB
Title of 12(b) Security	Depositary Shares for 1/20 of 7.00% Series B Mandatory Convertible Preferred Stock, $0.01 par value
Security Exchange Name	NYSE
9.15% First Mortgage Bonds Due 2021 [Member] | New York Stock Exchange [Member] | Houston Electric [Member]
Entity Information [Line Items]
Trading Symbol	n/a
Title of 12(b) Security	9.15% First Mortgage Bonds due 2021
Security Exchange Name	NYSE
6.95% General Mortgage Bonds Due 2033 [Member] | New York Stock Exchange [Member] | Houston Electric [Member]
Entity Information [Line Items]
Trading Symbol	n/a
Title of 12(b) Security	6.95% General Mortgage Bonds due 2033
Security Exchange Name	NYSE
6.625% Senior Notes Due 2037 [Member] | New York Stock Exchange [Member] | CERC Corp [Member]
Entity Information [Line Items]
Trading Symbol	n/a
Title of 12(b) Security	6.625% Senior Notes due 2037
Security Exchange Name	NYSE

CONDENSED STATEMENTS OF CONSOLI

CONDENSED STATEMENTS OF CONSOLIDATED INCOME (Unaudited) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues:
Utility revenues		$ 1,555	$ 1,341	$ 3,716	$ 3,235
Non-utility revenues		1,243	845	2,613	2,106
Total		2,798	2,186	6,329	5,341
Expenses:
Utility natural gas, fuel and purchased power		264	188	999	825
Non-utility cost of revenues, including natural gas	[1]	910	790	2,161	2,063
Operation and maintenance		884	578	1,745	1,147
Depreciation and amortization		340	342	653	656
Taxes other than income taxes		113	101	239	212
Total		2,511	1,999	5,797	4,903
Operating Income		287	187	532	438
Other Income (Expense):
Gain on marketable securities		64	22	147	23
Loss on indexed debt securities		(68)	(254)	(154)	(272)
Interest and other finance charges		(134)	(91)	(255)	(169)
Interest on Securitization Bonds		(10)	(14)	(22)	(30)
Equity in earnings of unconsolidated affiliates, net		74	58	136	127
Other income (expense), net		11	4	31	7
Total		(63)	(275)	(117)	(314)
Income (Loss) Before Income Taxes		224	(88)	415	124
Income tax expense (benefit)		29	(13)	51	34
Net Income (Loss)		195	(75)	364	90
Preferred stock dividend requirement		30	0	59	0
Income (Loss) Available to Common Shareholders		$ 165	$ (75)	$ 305	$ 90
Basic Earnings (Loss) Per Common Share		$ 0.33	$ (0.17)	$ 0.61	$ 0.21
Diluted Earnings (Loss) Per Common Share		$ 0.33	$ (0.17)	$ 0.61	$ 0.21
Weighted Average Common Shares Outstanding, Basic		502,200,000	431,523,000	501,862,000	431,378,000
Weighted Average Common Shares Outstanding, Diluted		504,831,000	431,523,000	504,493,000	434,407,000
Houston Electric [Member]
Revenues:
Total		$ 765	$ 854	$ 1,451	$ 1,609
Expenses:
Operation and maintenance		359	351	727	693
Depreciation and amortization		176	262	351	495
Taxes other than income taxes		61	60	123	121
Total		596	673	1,201	1,309
Operating Income		169	181	250	300
Other Income (Expense):
Interest and other finance charges		(42)	(36)	(82)	(69)
Interest on Securitization Bonds		(10)	(14)	(22)	(30)
Other income (expense), net		6	(3)	10	(6)
Total		(46)	(53)	(94)	(105)
Income (Loss) Before Income Taxes		123	128	156	195
Income tax expense (benefit)		23	27	29	42
Net Income (Loss)		100	101	127	153
CERC Corp [Member]
Revenues:
Utility revenues		503	487	1,688	1,630
Non-utility revenues		839	841	2,022	2,098
Total		1,342	1,328	3,710	3,728
Expenses:
Utility natural gas, fuel and purchased power		190	188	815	825
Non-utility cost of revenues, including natural gas	[1]	769	790	1,940	2,063
Operation and maintenance		211	217	461	455
Depreciation and amortization		76	72	153	145
Taxes other than income taxes		38	39	87	87
Total		1,284	1,306	3,456	3,575
Operating Income		58	22	254	153
Other Income (Expense):
Interest and other finance charges		(30)	(33)	(59)	(62)
Other income (expense), net		0	(1)	(3)	(5)
Total		(30)	(34)	(62)	(67)
Income (Loss) Before Income Taxes		28	(12)	192	86
Income tax expense (benefit)		0	(4)	26	16
Income (Loss) From Continuing Operations		28	(8)	166	70
Income from discontinued operations (net of tax of $-0-, $14, $-0- and $31, respectively)		0	44	0	96
Net Income (Loss)		$ 28	$ 36	$ 166	$ 166
[1]	Income statement impact associated with cash flow hedge activity is related to gains and losses reclassified from Accumulated other comprehensive income into income. Amounts are immaterial for each Registrant in the three and six months ended June 30, 2019 and 2018, respectively.

CONDENSED STATEMENTS OF CONSO_2

CONDENSED STATEMENTS OF CONSOLIDATED INCOME (Parentheticals) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
CERC Corp [Member]
Income tax expense associated with discontinued operations	$ 0	$ 14	$ 0	$ 31

CONDENSED STATEMENTS OF CONSO_3

CONDENSED STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net income (Loss)	$ 195	$ (75)	$ 364	$ 90
Other comprehensive income (loss):
Adjustment to pension and other postretirement plans (net of tax of $1, $-0-, $2 and $1)	2	2	3	3
Net deferred gain (loss) from cash flow hedges (net of tax of $-0-, $-0-, $-0- and $1)	0	(1)	(1)	3
Reclassification of deferred loss from cash flow hedges realized in net income (net of tax of $-0-, $-0-, $-0- and $-0-)	0	0	1	0
Total	2	1	3	6
Comprehensive income (loss)	197	(74)	367	96
Houston Electric [Member]
Net income (Loss)	100	101	127	153
Other comprehensive income (loss):
Net deferred gain (loss) from cash flow hedges (net of tax of $-0-, $-0-, $-0- and $1)	0	0	(1)	4
Total	0	0	(1)	4
Comprehensive income (loss)	100	101	126	157
CERC Corp [Member]
Net income (Loss)	28	36	166	166
Other comprehensive income (loss):
Total	0	0	0	0
Comprehensive income (loss)	$ 28	$ 36	$ 166	$ 166

CONDENSED STATEMENTS OF CONSO_4

CONDENSED STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Parentheticals) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Tax benefit (expense) on adjustment related to pension and postretirement plans	$ (1,000,000)	$ 0	$ (2,000,000)	$ (1,000,000)
Tax expense (benefit) on net deferred gain (loss) from cash flow hedges	0	0	0	1,000,000
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	0	0	0	0
Houston Electric [Member]
Tax expense (benefit) on net deferred gain (loss) from cash flow hedges	$ 0	$ 0	$ 0	$ 1,000,000

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Current Assets:
Cash and cash equivalents	$ 271	$ 4,231
Investment in marketable securities	687	540
Accounts receivable, less bad debt reserve	1,173	1,190
Accrued unbilled revenues	365	378
Natural gas inventory	212	194
Materials and supplies	267	200
Non-trading derivative assets	101	100
Taxes receivable	69	0
Prepaid expenses and other current assets	181	192
Total current assets	3,326	7,025
Property, Plant and Equipment:
Property, plant and equipment	29,552	20,267
Less: accumulated depreciation and amortization	9,620	6,223
Property, plant and equipment, net	19,932	14,044
Other Assets:
Goodwill	5,179	867
Regulatory assets	2,228	1,967
Notes receivable – unconsolidated affiliate	4	0
Non-trading derivative assets	44	38
Investment in unconsolidated affiliates	2,470	2,482
Preferred units – unconsolidated affiliate	363	363
Intangible assets, net	370	65
Other	273	158
Total other assets	10,931	5,940
Total Assets	34,189	27,009
Current Liabilities:
Current portion of VIE Securitization Bonds long-term debt	349	458
Indexed debt, net	22	24
Current portion of other long-term debt	117	0
Indexed debt securities derivative	755	601
Accounts payable	936	1,240
Taxes accrued	158	204
Interest accrued	157	121
Dividends accrued	0	187
Customer deposits	126	86
Non-trading derivative liabilities	33	126
Other	343	255
Total current liabilities	2,996	3,302
Other Liabilities:
Deferred income taxes, net	3,805	3,239
Non-trading derivative liabilities	18	5
Benefit obligations	872	796
Regulatory liabilities	3,467	2,525
Other	653	402
Total other liabilities	8,815	6,967
Long-term Debt:
VIE Securitization Bonds, net	845	977
Other long-term debt, net	13,276	7,705
Total long-term debt, net	14,121	8,682
Commitments and Contingencies (Note 14)
Shareholders’ Equity:
Cumulative preferred stock, $0.01 par value, 20,000,000 shares authorized
Common stock	5	5
Additional paid-in capital	6,065	6,072
Retained earnings	552	349
Accumulated other comprehensive income (loss)	(105)	(108)
Total shareholders’ equity	8,257	8,058
Total Liabilities and Shareholders’ Equity	34,189	27,009
Houston Electric [Member]
Current Assets:
Cash and cash equivalents	260	335
Accounts and notes receivable, less bad debt reserve	327	283
Accounts and notes receivable–affiliated companies	831	20
Accrued unbilled revenues	122	110
Materials and supplies	142	135
Taxes receivable	13	5
Prepaid expenses and other current assets	41	61
Total current assets	1,736	949
Property, Plant and Equipment:
Property, plant and equipment	12,457	12,148
Less: accumulated depreciation and amortization	3,762	3,746
Property, plant and equipment, net	8,695	8,402
Other Assets:
Regulatory assets	1,016	1,124
Other	31	32
Total other assets	1,047	1,156
Total Assets	11,478	10,507
Current Liabilities:
Current portion of VIE Securitization Bonds long-term debt	349	458
Accounts payable	226	262
Accounts and notes payable–affiliated companies	59	78
Taxes accrued	63	115
Interest accrued	82	64
Non-trading derivative liabilities	0	24
Other	73	89
Total current liabilities	852	1,090
Other Liabilities:
Deferred income taxes, net	1,010	1,023
Benefit obligations	87	91
Regulatory liabilities	1,286	1,298
Other	69	65
Total other liabilities	2,452	2,477
Long-term Debt:
VIE Securitization Bonds, net	845	977
Other long-term debt, net	3,971	3,281
Total long-term debt, net	4,816	4,258
Commitments and Contingencies (Note 14)
Shareholders’ Equity:
Common stock	0	0
Additional paid-in capital	2,486	1,896
Retained earnings	887	800
Accumulated other comprehensive income (loss)	(15)	(14)
Total shareholders’ equity	3,358	2,682
Total Liabilities and Shareholders’ Equity	11,478	10,507
CERC Corp [Member]
Current Assets:
Cash and cash equivalents	1	14
Accounts receivable, less bad debt reserve	506	894
Accounts and notes receivable–affiliated companies	192	120
Accrued unbilled revenues	90	268
Natural gas inventory	159	194
Materials and supplies	71	65
Non-trading derivative assets	101	100
Prepaid expenses and other current assets	39	115
Total current assets	1,159	1,770
Property, Plant and Equipment:
Property, plant and equipment	7,710	7,431
Less: accumulated depreciation and amortization	2,306	2,205
Property, plant and equipment, net	5,404	5,226
Other Assets:
Goodwill	867	867
Regulatory assets	187	181
Non-trading derivative assets	44	38
Other	154	132
Total other assets	1,252	1,218
Total Assets	7,815	8,214
Current Liabilities:
Accounts payable	406	856
Accounts and notes payable–affiliated companies	45	50
Taxes accrued	51	82
Interest accrued	38	38
Customer deposits	74	75
Non-trading derivative liabilities	28	102
Other	132	137
Total current liabilities	774	1,340
Other Liabilities:
Deferred income taxes, net	446	406
Non-trading derivative liabilities	7	5
Benefit obligations	94	93
Regulatory liabilities	1,234	1,227
Other	357	329
Total other liabilities	2,138	2,060
Long-term Debt:
Total long-term debt, net	2,397	2,371
Commitments and Contingencies (Note 14)
Shareholders’ Equity:
Common stock	0	0
Additional paid-in capital	2,015	2,015
Retained earnings	486	423
Accumulated other comprehensive income (loss)	5	5
Total shareholders’ equity	2,506	2,443
Total Liabilities and Shareholders’ Equity	7,815	8,214
Series A Preferred Stock [Member]
Shareholders’ Equity:
Preferred Stock, $0.01 par value	790	790
Series B Preferred Stock [Member]
Shareholders’ Equity:
Preferred Stock, $0.01 par value	$ 950	$ 950

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Cash and cash equivalents	$ 271	$ 4,231
Accounts receivable, less bad debt reserve	1,173	1,190
Bad debt reserve	27	18
Prepaid expenses and other current assets	181	192
Regulatory assets	$ 2,228	$ 1,967
Preferred stock par value (in dollars per share)	$ 0.01
Cumulative preferred stock authorized (in shares)	20,000,000
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)	502,214,639	501,197,784
Variable Interest Entity, Primary Beneficiary [Member]
Cash and cash equivalents	$ 260	$ 335
Accounts receivable, less bad debt reserve	77	56
Prepaid expenses and other current assets	33	34
Regulatory assets	895	1,059
Houston Electric [Member]
Cash and cash equivalents	260	335
Bad debt reserve	1	1
Prepaid expenses and other current assets	41	61
Regulatory assets	1,016	1,124
Houston Electric [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Cash and cash equivalents	260	335
Accounts receivable, less bad debt reserve	77	56
Prepaid expenses and other current assets	33	34
Regulatory assets	895	1,059
CERC Corp [Member]
Cash and cash equivalents	1	14
Accounts receivable, less bad debt reserve	506	894
Bad debt reserve	21	17
Prepaid expenses and other current assets	39	115
Regulatory assets	$ 187	$ 181
Cumulative Preferred Stock [Member]
Preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Cumulative preferred stock authorized (in shares)	20,000,000	20,000,000
Series A Preferred Stock [Member]
Preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock aggregate liquidation preference	$ 800	$ 800
Preferred stock outstanding (in shares)	800,000	800,000
Series B Preferred Stock [Member]
Preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock aggregate liquidation preference	$ 977.5	$ 977.5
Preferred stock outstanding (in shares)	977,500	977,500

CONDENSED STATEMENTS OF CONSO_5

CONDENSED STATEMENTS OF CONSOLIDATED CASH FLOWS (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash Flows from Operating Activities:
Net income	$ 364	$ 90
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	653	656
Amortization of deferred financing costs	14	18
Amortization of intangible assets in non-utility cost of revenues	12	0
Deferred income taxes	(21)	(12)
Unrealized gain on marketable securities	(147)	(23)
Loss on indexed debt securities	154	272
Write-down of natural gas inventory	3	1
Equity in earnings of unconsolidated affiliates, net of distributions	12	(9)
Pension contributions	(29)	(64)
Changes in other assets and liabilities, excluding acquisitions:
Accounts receivable and unbilled revenues, net	463	232
Inventory	10	52
Accounts payable	(594)	(246)
Taxes receivable	(69)	(39)
Fuel cost recovery	78	69
Non-trading derivatives, net	(71)	64
Margin deposits, net	(12)	(9)
Interest and taxes accrued	(88)	(64)
Net regulatory assets and liabilities	(77)	57
Other current assets	20	(4)
Other current liabilities	(156)	(13)
Other assets	76	(3)
Other liabilities	(30)	60
Other operating activities, net	9	8
Net cash provided by operating activities	574	1,093
Cash Flows from Investing Activities:
Capital expenditures	(1,169)	(697)
Acquisitions, net of cash acquired	(5,987)	0
Distributions from unconsolidated affiliate in excess of cumulative earnings	0	30
Proceeds from sale of marketable securities	0	398
Increase in notes receivable–affiliated companies	(4)	0
Other investing activities, net	11	2
Net cash used in investing activities	(7,149)	(267)
Cash Flows from Financing Activities:
Decrease in short-term borrowings, net	0	(39)
Proceeds from (payments of) commercial paper, net	2,221	(1,188)
Proceeds from long-term debt, net	1,721	997
Payments of long-term debt	(1,077)	(230)
Long-term revolving credit facility	135	0
Debt issuance costs	(9)	(35)
Payment of dividends on Common Stock	(288)	(240)
Payment of dividends on Preferred Stock	(60)	0
Distribution to ZENS note holders	0	(16)
Other financing activities, net	(14)	(5)
Net cash provided by (used in) financing activities	2,629	(756)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(3,946)	70
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	4,278	296
Cash, Cash Equivalents and Restricted Cash at End of Period	332	366
Houston Electric [Member]
Cash Flows from Operating Activities:
Net income	127	153
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	351	495
Amortization of deferred financing costs	5	6
Deferred income taxes	(27)	(38)
Changes in other assets and liabilities, excluding acquisitions:
Accounts receivable and unbilled revenues, net	(56)	(107)
Accounts receivable/payable–affiliated companies	(35)	78
Inventory	(7)	(6)
Accounts payable	2	(6)
Taxes receivable	(8)	(23)
Non-trading derivatives, net	(25)	0
Interest and taxes accrued	(34)	(45)
Net regulatory assets and liabilities	(69)	(59)
Other current assets	18	4
Other current liabilities	(4)	(11)
Other assets	10	2
Other liabilities	(3)	2
Other operating activities, net	(5)	(2)
Net cash provided by operating activities	240	443
Cash Flows from Investing Activities:
Capital expenditures	(514)	(441)
Increase in notes receivable–affiliated companies	(794)	(26)
Other investing activities, net	(3)	(1)
Net cash used in investing activities	(1,311)	(468)
Cash Flows from Financing Activities:
Proceeds from long-term debt, net	696	398
Payments of long-term debt	(242)	(230)
Decrease in notes payable–affiliated companies	(1)	(60)
Dividend to parent	(40)	(63)
Contribution from parent	590	0
Debt issuance costs	(8)	(4)
Other financing activities, net	(1)	1
Net cash provided by (used in) financing activities	994	42
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(77)	17
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	370	274
Cash, Cash Equivalents and Restricted Cash at End of Period	293	291
CERC Corp [Member]
Cash Flows from Operating Activities:
Net income	166	166
Less: Income from discontinued operations, net of tax	0	96
Income from continuing operations	166	70
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	153	145
Amortization of deferred financing costs	4	4
Deferred income taxes	20	9
Write-down of natural gas inventory	3	1
Changes in other assets and liabilities, excluding acquisitions:
Accounts receivable and unbilled revenues, net	554	339
Accounts receivable/payable–affiliated companies	(11)	(14)
Inventory	26	58
Accounts payable	(442)	(248)
Fuel cost recovery	78	69
Non-trading derivatives, net	(62)	61
Margin deposits, net	(12)	(9)
Interest and taxes accrued	(31)	(20)
Net regulatory assets and liabilities	15	92
Other current assets	7	7
Other current liabilities	(21)	8
Other assets	(2)	4
Other liabilities	3	52
Other operating activities, net	1	0
Net cash provided by operating activities from continuing operations	449	628
Net cash provided by operating activities from discontinued operations	0	118
Net cash provided by operating activities	449	746
Cash Flows from Investing Activities:
Capital expenditures	(322)	(230)
Increase in notes receivable–affiliated companies	(66)	0
Other investing activities, net	2	3
Net cash used in investing activities from continuing operations	(386)	(227)
Net cash provided by investing activities from discontinued operations	0	30
Net cash used in investing activities	(386)	(197)
Cash Flows from Financing Activities:
Decrease in short-term borrowings, net	0	(39)
Proceeds from (payments of) commercial paper, net	22	(333)
Proceeds from long-term debt, net	0	599
Decrease in notes payable–affiliated companies	0	(570)
Dividend to parent	(103)	(211)
Contribution from parent	0	0
Debt issuance costs	0	(5)
Other financing activities, net	(2)	(1)
Net cash used in financing activities from continuing operations	(83)	(560)
Net cash provided by financing activities from discontinued operations	0	0
Net cash provided by (used in) financing activities	(83)	(560)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(20)	(11)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	25	12
Cash, Cash Equivalents and Restricted Cash at End of Period	$ 5	$ 1

CONDENSED STATEMENTS OF CONSO_6

CONDENSED STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Houston Electric [Member]	Houston Electric [Member]Common Stock [Member]	Houston Electric [Member]Additional Paid-in Capital [Member]	Houston Electric [Member]Retained Earnings [Member]	Houston Electric [Member]AOCI Attributable to Parent [Member]	CERC Corp [Member]	CERC Corp [Member]Common Stock [Member]	CERC Corp [Member]Additional Paid-in Capital [Member]	CERC Corp [Member]Retained Earnings [Member]	CERC Corp [Member]AOCI Attributable to Parent [Member]	Preferred Class B [Member]Retained Earnings [Member]	Common Stock [Member]Retained Earnings [Member]
Balance, beginning of period at Dec. 31, 2017		0
Balance, end of period at Jun. 30, 2018		0
Balance, beginning of period at Dec. 31, 2017			431,000,000					1,000					1,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0
Balance, end of period at Jun. 30, 2018			431,000,000					1,000					1,000
Balance, beginning of period at Dec. 31, 2017		$ 0	$ 4	$ 4,209	$ 543	$ (68)		$ 0	$ 1,696	$ 673	$ 0		$ 0	$ 2,528	$ 574	$ 6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0	6
Contribution From Parent									0
Other									1					0
Net income (Loss)	$ 90				90		$ 153			153		$ 166			166
Dividends																		$ (120)
Dividend to parent										(63)					(211)
Other comprehensive income (loss)						6					4
Balance, end of period at Jun. 30, 2018	4,670	$ 0	$ 4	4,215	513	(62)	2,464	$ 0	1,697	763	4	3,063	$ 0	2,528	529	6
Balance, beginning of period at Mar. 31, 2018		0
Balance, end of period at Jun. 30, 2018		0
Balance, beginning of period at Mar. 31, 2018			431,000,000					1,000					1,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0
Balance, end of period at Jun. 30, 2018			431,000,000					1,000					1,000
Balance, beginning of period at Mar. 31, 2018		$ 0	$ 4	4,208	708	(63)		$ 0	1,697	693	4		$ 0	2,527	618	6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0	7
Contribution From Parent									0
Other									0					1
Net income (Loss)	(75)				(75)		101			101		36			36
Dividends																		(120)
Dividend to parent										(31)					(125)
Other comprehensive income (loss)						1					0
Balance, end of period at Jun. 30, 2018	$ 4,670	$ 0	$ 4	4,215	513	(62)	2,464	$ 0	1,697	763	4	3,063	$ 0	2,528	529	6
Balance, beginning of period at Dec. 31, 2018		2,000,000
Balance, end of period at Jun. 30, 2019		2,000,000
Balance, beginning of period at Dec. 31, 2018	501,197,784		501,000,000					1,000					1,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			1,000,000
Balance, end of period at Jun. 30, 2019	502,214,639		502,000,000					1,000					1,000
Balance, beginning of period at Dec. 31, 2018	$ 8,058	$ 1,740	$ 5	6,072	349	(108)	2,682	$ 0	1,896	800	(14)	2,443	$ 0	2,015	423	5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0	(7)
Contribution From Parent									590
Other									0					0
Net income (Loss)	364				364		127			127		166			166
Dividends																	$ (17)	(144)
Dividend to parent										(40)					(103)
Other comprehensive income (loss)						3					(1)
Balance, end of period at Jun. 30, 2019	$ 8,257	$ 1,740	$ 5	6,065	552	(105)	3,358	$ 0	2,486	887	(15)	2,506	$ 0	2,015	486	5
Balance, beginning of period at Mar. 31, 2019		2,000,000
Balance, end of period at Jun. 30, 2019		2,000,000
Balance, beginning of period at Mar. 31, 2019			502,000,000					1,000					1,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0
Balance, end of period at Jun. 30, 2019	502,214,639		502,000,000					1,000					1,000
Balance, beginning of period at Mar. 31, 2019		$ 1,740	$ 5	6,060	518	(107)		$ 0	2,486	803	(15)		$ 0	2,015	541	5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances related to benefit and investment plans			0	5
Contribution From Parent									0
Other									0					0
Net income (Loss)	$ 195				195		100			100		28			28
Dividends																	$ (17)	$ (144)
Dividend to parent										(16)					(83)
Other comprehensive income (loss)						2					0
Balance, end of period at Jun. 30, 2019	$ 8,257	$ 1,740	$ 5	$ 6,065	$ 552	$ (105)	$ 3,358	$ 0	$ 2,486	$ 887	$ (15)	$ 2,506	$ 0	$ 2,015	$ 486	$ 5

CONDENSED STATEMENTS OF CONSO_7

CONDENSED STATEMENTS OF CONSOLIDATED CHANGES IN EQUITY (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Class of Stock [Line Items]
Cumulative preferred stock par value (in dollars per share)	$ 0.01		$ 0.01
Cumulative preferred stock shares authorized (in shares)	20,000,000		20,000,000
Common stock shares par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01
Common stock shares authorized (in shares)	1,000,000,000	1,000,000,000	1,000,000,000	1,000,000,000	1,000,000,000
Common Stock dividends declared ($0.2875, $0.2775, $0.2875 and $0.2775 per share, respectively)	$ 0.2875	$ 0.2775	$ 0.2875	$ 0.2775
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Cumulative preferred stock par value (in dollars per share)	0.01		0.01		$ 0.01
Series B Preferred Stock dividends declared ($17.5000, $-0-, $17.5000, and $-0- per share, respectively)	0	0	0	0
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Cumulative preferred stock par value (in dollars per share)	0.01		0.01		$ 0.01
Series B Preferred Stock dividends declared ($17.5000, $-0-, $17.5000, and $-0- per share, respectively)	$ 17.5000	$ 0	$ 17.5000	$ 0

Background and Basis of Present

Background and Basis of Presentation	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background and Basis of Presentation [Text Block]	Background and Basis of Presentation General. This combined Form 10-Q is filed separately by three registrants: CenterPoint Energy, Inc., CenterPoint Energy Houston Electric, LLC and CenterPoint Energy Resources Corp. Information contained herein relating to any individual registrant is filed by such registrant solely on its own behalf. Each registrant makes no representation as to information relating exclusively to the other Registrants or the subsidiaries of CenterPoint Energy other than itself or its subsidiaries. Except as discussed in the last paragraph in Note 12 to the Registrants’ Condensed Consolidated Financial Statements, no registrant has an obligation in respect of any other Registrant’s debt securities, and holders of such debt securities should not consider the financial resources or results of operations of any Registrant other than the obligor in making a decision with respect to such securities. 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 and specific references to Houston Electric and CERC herein also pertain to CenterPoint Energy, unless otherwise indicated. The Interim Condensed Financial Statements are unaudited, omit certain financial statement disclosures and should be read with the Registrants’ combined 2018 Form 10-K. Background. CenterPoint Energy, Inc. is a public utility holding company and owns interests in Enable as described below. On the Merger Date, pursuant to the Merger Agreement, CenterPoint Energy consummated the previously announced Merger and acquired Vectren for approximately $6 billion in cash. On the Merger Date, Vectren became a wholly-owned subsidiary of CenterPoint Energy. As of June 30, 2019 , CenterPoint Energy’s operating subsidiaries were as follows: • Houston Electric owns and operates electric transmission and distribution facilities in the Texas Gulf Coast area that includes the city of Houston; and • CERC (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 over 30 states through its wholly-owned subsidiary, CES. • Vectren holds three public utilities through its wholly-owned subsidiary, VUHI, a public utility holding company: • Indiana Gas provides energy delivery services to natural gas customers located in central and southern Indiana; • SIGECO provides energy delivery services to electric and natural gas customers located near Evansville in southwestern Indiana and owns and operates electric generation assets to serve its electric customers and optimizes those assets in the wholesale power market; and • VEDO provides energy delivery services to natural gas customers located near Dayton in west-central Ohio. • Vectren performs non-utility activities through: • Infrastructure Services, which provides underground pipeline construction and repair services through wholly-owned subsidiaries Miller Pipeline, LLC and Minnesota Limited, LLC and serves natural gas utilities across the United States, focusing on recurring integrity, station and maintenance work and opportunities for large transmission pipeline construction projects; and • ESG, which provides energy performance contracting and sustainable infrastructure services, such as renewables, distributed generation and combined heat and power projects. As of June 30, 2019 , CenterPoint Energy, indirectly through CNP Midstream, owned approximately 53.8% of the common units representing limited partner interests in Enable, 50% of the management rights and 40% of the incentive distribution rights in Enable GP and also directly owned an aggregate of 14,520,000 Enable Series A Preferred Units. Enable owns, operates and develops natural gas and crude oil infrastructure assets. As of June 30, 2019 , 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 solely 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. See Note 9 for further discussion. Concurrent with the completion of the Merger, CenterPoint Energy added two new reportable segments, Indiana Electric Integrated and Infrastructure Services, to its five reportable segments disclosed in the Registrants’ combined 2018 Form 10-K. Additionally, CenterPoint Energy’s Natural Gas Distribution reportable segment now includes the gas operations of SIGECO (Indiana South), Indiana Gas and VEDO and CenterPoint Energy’s Corporate and Other reportable segment now includes ESG. Houston Electric’s and CERC’s reportable segments were not impacted by the Merger. For a description of the Registrants’ reportable segments, see Note 16 . Significant Accounting Policies. In addition to the significant accounting policies disclosed in the Registrants’ combined 2018 Form 10-K, CenterPoint Energy has adopted the following new or enhanced significant accounting policies subsequent to the consummation of the Merger: Principles of Consolidation . Businesses within the Infrastructure Services reportable segment provide underground pipeline construction and repair services for customers that include NGD utilities. In accordance with consolidation guidance in ASC 980—Regulated Operations, costs incurred by NGD utilities for these pipeline construction and repair services are not eliminated in consolidation when capitalized and included in rate base by the NGD utility. Guarantees . CenterPoint Energy recognizes guarantee obligations at fair value. CenterPoint Energy discloses parent company guarantees of a subsidiary’s obligation when that guarantee results in the exposure of a material obligation of the parent company even if the probability of fulfilling such obligation is considered remote. See Note 14 (b). Income Taxes . Investment tax credits are deferred and amortized to income over the approximate lives of the related property. MISO Transactions . Indiana Electric is a member of MISO. MISO-related purchase and sale transactions are recorded using settlement information provided by the MISO. These purchase and sale transactions are accounted for on at least a net hourly position, meaning net purchases within that interval are recorded on CenterPoint Energy’s Condensed Statements of Consolidated Income in Utility natural gas, fuel and purchased power, and net sales within that interval are recorded on CenterPoint Energy’s Condensed Statements of Consolidated Income in Utility revenues. On occasion, prior period transactions are resettled outside the routine process due to a change in the MISO’s tariff or a material interpretation thereof. Expenses associated with resettlements are recorded once the resettlement is probable and the resettlement amount can be estimated. Revenues associated with resettlements are recognized when the amount is determinable and collectability is reasonably assured.

Mergers and Acquisitions (Cente

Mergers and Acquisitions (CenterPoint Energy)	6 Months Ended
	Jun. 30, 2019
Business Combinations [Abstract]
Mergers and Acquisitions (CenterPoint Energy) [Text Block]	Mergers and Acquisitions (CenterPoint Energy) Merger with Vectren. On the Merger Date, pursuant to the Merger Agreement, CenterPoint Energy consummated the previously announced Merger and acquired Vectren for approximately $6 billion in cash. Each share of Vectren common stock issued and outstanding immediately prior to the closing was canceled and converted into the right to receive $72.00 in cash per share, without interest. At the closing, each stock unit payable in Vectren common stock or whose value is determined with reference to the value of Vectren common stock, whether vested or unvested, was canceled with cash consideration paid in accordance with the terms of the Merger Agreement. These amounts did not include a stub period cash dividend of $0.41145 per share, which was declared, with CenterPoint Energy’s consent, by Vectren’s board of directors on January 16, 2019 , and paid to Vectren stockholders as of the record date of February 1, 2019 . Pursuant to the Merger Agreement and immediately subsequent to the close of the Merger, CenterPoint Energy cash settled $78 million in outstanding share-based awards issued prior to the Merger Date by Vectren to its employees. As a result of the Merger, CenterPoint Energy assumed a liability for these share-based awards of $41 million and recorded an incremental cost of $37 million in Operation and maintenance expenses on its Condensed Statements of Consolidated Income during the six months ended June 30, 2019 for the accelerated vesting of the awards in accordance with the Merger Agreement. Subsequent to the close of the Merger, CenterPoint Energy recognized severance totaling $61 million to employees terminated immediately subsequent to the Merger close, inclusive of change of control severance payments to executives of Vectren under existing agreements, and which is included in Operation and maintenance expenses on its Condensed Statements of Consolidated Income during the six months ended June 30, 2019. In connection with the Merger, VUHI and VCC made offers to prepay certain outstanding guaranteed senior notes as required pursuant to certain note purchase agreements previously entered into by VUHI and VCC. See Note 12 for further details. Following the closing, shares of Vectren common stock, which previously traded under the ticker symbol “VVC” on the NYSE, ceased trading on and were delisted from the NYSE. The Merger is being accounted for in accordance with ASC 805, Business Combinations, with CenterPoint Energy as the accounting acquirer of Vectren. Identifiable assets acquired and liabilities assumed have been recorded at their estimated fair values on the Merger Date. Vectren’s regulated operations, comprised of electric generation and electric and natural gas energy delivery services, are subject to the rate-setting authority of the FERC, the IURC and the PUCO, and are accounted for pursuant to U.S. generally accepted accounting principles for regulated operations. The rate-setting and cost-recovery provisions currently in place for Vectren’s regulated operations provide revenues derived from costs including a return on investment of assets and liabilities included in rate base. Thus, the fair values of Vectren’s tangible and intangible assets and liabilities subject to these rate-setting provisions approximate their carrying values. Accordingly, neither the assets and liabilities acquired, nor the unaudited pro forma financial information, reflect any adjustments related to these amounts. The fair value of regulatory assets not earning a return have been determined using the income approach and are considered Level 3 fair value measurements due to the use of significant judgmental and unobservable inputs. The fair value of Vectren’s assets acquired and liabilities assumed that are not subject to the rate-setting provisions, including identifiable intangibles, have been determined using the income approach and the market approach. The valuation of Vectren’s long-term debt is primarily considered a Level 2 fair value measurement. All other valuations are considered Level 3 fair value measurements due to the use of significant judgmental and unobservable inputs, including projected timing and amount of future cash flows and discount rates reflecting risk inherent in the future market prices. The following table presents the preliminary purchase price allocation as of June 30, 2019 (in millions): Cash and cash equivalents $ 16 Other current assets 598 Property, plant and equipment, net 5,146 Identifiable intangibles 322 Regulatory assets 338 Other assets 151 Total assets acquired 6,571 Current liabilities 690 Regulatory liabilities 944 Other liabilities 860 Long-term debt 2,401 Total liabilities assumed 4,895 Net assets acquired 1,676 Goodwill 4,306 Total purchase price consideration $ 5,982 CenterPoint Energy has not completed a final valuation analysis necessary to determine the fair market values of all of Vectren’s assets and liabilities or the allocation of its purchase price. The final allocation could differ materially from this preliminary purchase price allocation and, as such, no assurances can be provided regarding the preliminary purchase accounting. The final allocation may include changes in the fair value of (1) property, plant and equipment, (2) intangible assets and goodwill, (3) deferred taxes, (4) regulatory assets and liabilities, (5) long-term debt and (6) other assets and liabilities. Changes in the preliminary purchase price allocation since the initial estimates reported in the first quarter of 2019 primarily included additional information obtained related to intangible assets. The excess of the purchase price over the estimated fair values of the assets acquired and liabilities assumed is recognized as goodwill, which is primarily attributable to significant potential strategic benefits to CenterPoint Energy, including growth opportunities for more rate-regulated investment, more customers for existing products and services and additional products and services for existing customers. Additionally, CenterPoint Energy believes the Merger will increase geographic and business diversity as well as scale in attractive jurisdictions and economies. CenterPoint Energy anticipates that the value assigned to goodwill will not be deductible for tax purposes. The estimated fair value of the identifiable intangible assets and related useful lives as included in the preliminary purchase price allocation include: Weighted Average Useful Lives Estimated Fair Value (in years) (in millions) Operation and maintenance agreements 24 $ 12 Customer relationships 18 220 Construction backlog 1 28 Trade names 10 62 Total $ 322 Amortization expense related to the operation and maintenance agreements and construction backlog was $3 million and $12 million , inclusive of a $4 million benefit related to a cumulative catch-up for remeasurement of the purchase price allocation, for the three and six months ended June 30, 2019, respectively, and is included in Non-utility cost of revenues, including natural gas on CenterPoint Energy’s Condensed Statements of Consolidated Income. Amortization expense related to customer relationships and trade names was $5 million and $8 million for the three and six months ended June 30, 2019, respectively, and is included in Depreciation and amortization expense on CenterPoint Energy’s Condensed Statements of Consolidated Income. The results of operations for Vectren included in CenterPoint Energy’s Interim Condensed Financial Statements from the Merger Date are as follows: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (in millions) Operating revenues $ 688 $ 1,161 Net income 38 19 The following unaudited pro forma financial information reflects the consolidated results of operations of CenterPoint Energy, assuming the Merger had taken place on January 1, 2018. The unaudited pro forma financial information has been presented for illustrative purposes only and is not necessarily indicative of the consolidated results of operations that would have been achieved had the Merger taken place on the dates indicated or of the future consolidated results of operations of the combined company. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Operating revenues $ 2,798 $ 2,830 $ 6,575 $ 6,644 Net income (loss) 199 (24 ) (1) 371 (2) 83 (3) (1) Pro forma net income was adjusted to exclude $10 million and $27 million , respectively, of Vectren and CenterPoint Energy Merger-related transaction costs incurred in 2018 and reflected in the historical income statements. (2) Pro forma net income was adjusted to exclude $37 million of Vectren Merger-related transaction costs incurred in 2019. (3) Pro forma net income was adjusted to include $46 million and $1 million , respectively, of Vectren and CenterPoint Energy Merger-related transaction costs incurred from July 1, 2018 to June 30, 2019. CenterPoint Energy incurred integration costs in connection with the Merger of $40 million and $48 million for the three and six months ended June 30, 2019, respectively, which were included in Operation and maintenance expenses in CenterPoint Energy’s Condensed Statements of Consolidated Income. Acquisition of Utility Pipeline Construction Company. An acquisition was made during the six months ended June 30, 2019 by CenterPoint Energy’s Infrastructure Services reportable segment, resulting in goodwill and intangible assets of approximately $6 million and $8 million , respectively. The intangible assets primarily relate to backlog and customer relationships. The initial purchase price of $21 million is subject to change due to a working capital adjustment clause, and the purchase price allocation also is preliminary and subject to change. The results of operations for the acquired company have been included in the consolidated financial statements from the date of acquisition and are not significant to the consolidated financial results of CenterPoint Energy. Pro forma results of operations have not been presented for the acquisition because the effects of the acquisition were not significant to CenterPoint Energy’s consolidated financial results for all periods presented.

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Jun. 30, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements [Text Block]	New Accounting Pronouncements The following table provides an overview of certain 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 2016-02- Leases (Topic 842) and related amendments 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 January 1, 2019 The Registrants adopted the standard and recognized a right-of-use asset and lease liability on their statement of financial position with no material impact on their results of operations and cash flows. See Note 19 for more information. Issued, Not Yet Effective Accounting Standards ASU Number and Name Description Effective Date Financial Statement Impact upon Adoption ASU 2016-13- Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments This standard, including standards amending this standard, requires a new model called CECL to estimate credit losses for (1) financial assets subject to credit losses and measured at amortized cost and (2) certain off-balance sheet credit exposures. Upon initial recognition of the exposure, the CECL model requires an entity to estimate the credit losses expected over the life of an exposure based on historical information, current information and reasonable and supportable forecasts, including estimates of prepayments. Transition method : modified retrospective January 1, 2020 Early adoption is permitted The Registrants are currently assessing the impact that this standard will have on their financial position, results of operations, cash flows and disclosures. ASU 2018-13- Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement This standard eliminates, modifies and adds certain disclosure requirements for fair value measurements. Transition method : prospective for additions and one modification and retrospective for all other amendments Adoption of eliminations and modifications as of September 30, 2018; Additions will be adopted January 1, 2020 The adoption of this standard did not impact the Registrants’ financial position, results of operations or cash flows. Note 8 reflects the disclosures modified upon adoption. ASU 2018-15- Intangibles-Goodwill and Other- Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract This standard aligns accounting for implementation costs incurred in a cloud computing arrangement that is accounted for as a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The update also prescribes the balance sheet, income statement, and cash flow classification of the capitalized implementation costs and related amortization expense and requires additional quantitative and qualitative disclosures. Transition method : retrospective or prospective January 1, 2020 Early adoption is permitted The adoption of this standard will allow the Registrants to capitalize certain implementation costs incurred in cloud computing arrangements that are accounted for as service contracts. 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. 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.

Revenue Recognition

Revenue Recognition	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue Recognition [Text Block]	Revenue Recognition In accordance with ASC 606, Revenue from Contracts with Customers, 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. The following tables disaggregate revenues by reportable segment and major source: CenterPoint Energy Three Months Ended June 30, 2019 Houston Electric T&D (1) Indiana Electric Integrated (1) Natural Gas Distribution (1) Energy Infrastructure Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 768 $ 140 $ 657 $ 87 $ 326 $ 78 $ 2,056 Derivatives income — — — 768 — — 768 Other (3) (3 ) — 3 — — 2 2 Eliminations — — (10 ) (17 ) (1 ) — (28 ) Total revenues $ 765 $ 140 $ 650 $ 838 $ 325 $ 80 $ 2,798 Six Months Ended June 30, 2019 Houston Electric T&D (1) Indiana Electric Integrated (1) (4) Natural Gas Distribution (1) (4) Energy Infrastructure Services (2) (4) Corporate and Other (2) (4) Total (in millions) Revenue from contracts $ 1,458 $ 223 $ 2,063 $ 260 $ 472 $ 119 $ 4,595 Derivatives income 3 — — 1,841 — — 1,844 Other (3) (7 ) — (4 ) — — 3 (8 ) Eliminations — — (20 ) (81 ) (1 ) — (102 ) Total revenues $ 1,454 $ 223 $ 2,039 $ 2,020 $ 471 $ 122 $ 6,329 Three Months Ended June 30, 2018 Houston Electric T&D (1) Indiana Natural Gas Distribution (1) Energy Infrastructure Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 860 $ — $ 509 $ 78 $ — $ 2 $ 1,449 Derivatives income — — — 782 — — 782 Other (3) (6 ) — (14 ) — — 2 (18 ) Eliminations — — (8 ) (19 ) — — (27 ) Total revenues $ 854 $ — $ 487 $ 841 $ — $ 4 $ 2,186 Six Months Ended June 30, 2018 Houston Electric T&D (1) Indiana Natural Gas Distribution (1) Energy Infrastructure Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 1,621 $ — $ 1,695 $ 256 $ — $ 3 $ 3,575 Derivatives income (4 ) — — 1,889 — — 1,885 Other (3) (12 ) — (47 ) — — 5 (54 ) Eliminations — — (18 ) (47 ) — — (65 ) Total revenues $ 1,605 $ — $ 1,630 $ 2,098 $ — $ 8 $ 5,341 (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. (4) Reflects revenues from Vectren subsidiaries for the period from February 1, 2019 to June 30, 2019. Houston Electric Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Revenue from contracts $ 768 $ 860 $ 1,458 $ 1,621 Other (1) (3 ) (6 ) (7 ) (12 ) Total revenues $ 765 $ 854 $ 1,451 $ 1,609 (1) 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. CERC Three Months Ended June 30, 2019 2018 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 $ 510 $ 87 $ — $ 597 $ 509 $ 78 $ — $ 587 Derivatives income — 768 — 768 — 782 — 782 Other (3) 3 — — 3 (14 ) — — (14 ) Eliminations (10 ) (16 ) — (26 ) (8 ) (19 ) — (27 ) Total revenues $ 503 $ 839 $ — $ 1,342 $ 487 $ 841 $ — $ 1,328 Six Months Ended June 30, 2019 2018 Natural Gas Distribution (1) Energy Services (2) Corporate and Other (2) Total Natural Gas Distribution (1) Energy Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 1,708 $ 260 $ 1 $ 1,969 $ 1,695 $ 256 $ — $ 1,951 Derivatives income — 1,841 — 1,841 — 1,889 — 1,889 Other (3) — — — — (47 ) — — (47 ) Eliminations (20 ) (80 ) — (100 ) (18 ) (47 ) — (65 ) Total revenues $ 1,688 $ 2,021 $ 1 $ 3,710 $ 1,630 $ 2,098 $ — $ 3,728 (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 Houston Electric T&D (CenterPoint Energy and Houston Electric). 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 state regulators, 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 state regulators. 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 state regulators. Payments are received on a monthly basis. Indiana Electric Integrated (CenterPoint Energy). Indiana Electric generates, distributes and transmits electricity to customers over time, and customers consume the electricity when delivered. Revenue, consisting of both volumetric and fixed tariff rates set by state regulators, is recognized as electricity is delivered and represents amounts both billed and unbilled. Customers are billed monthly and payment terms, set by the regulator, require payment within a month of billing. Natural Gas Distribution (CenterPoint Energy and CERC). Natural gas is distributed and transported 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 (CenterPoint Energy and CERC). 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. Infrastructure Services (CenterPoint Energy). Infrastructure Services provides u nderground pipeline construction and repair services. The contracts are generally less than one year in duration and consist of fixed price, unit, and time and material customer contracts. Under unit or time and material contracts, Infrastructure Services performs construction and repair services under specific work-orders at prices established by master service agreements. The performance obligation is defined at the work-order level. These services are billed to customers monthly or more frequently for work completed based on units completed or the costs of time and material incurred and generally require payment within 30 days of billing. Infrastructure Services has the right to consideration from customers in an amount that corresponds directly with the performance obligation satisfied, and therefore recognizes revenue at a point in time in the amount to which it has the right to invoice, which results in accrued unbilled revenues at the end of each accounting period. Under fixed price contracts, Infrastructure Services performs larger scale construction and repair services. Each contract is typically accounted for as a single performance obligation. Services performed under fixed price contracts are typically billed per the terms of the contract, which can range from completion of specific milestones to scheduled billing intervals. Billings occur monthly or more frequently for work completed and generally require payment within 30 days of billing. Revenue for fixed price contracts is recognized over time as control is transferred using the input method, considering costs incurred relative to total expected cost. Total expected cost is therefore a significant judgment affecting the amount and timing of revenue recognition. Infrastructure Services’ revenues are not subject to significant returns, refunds or warranty obligations. Contract Balances. When the timing of delivery of service is different from the timing of the payments made by customers and when the right to consideration is conditioned on something other than the passage of time, the Registrants recognize either a contract asset (performance precedes billing) or a contract liability (customer payment precedes performance). Those customers that prepay are represented by contract liabilities until the performance obligations are satisfied. The Registrants’ contract assets are included in Accrued unbilled revenues in their Condensed Consolidated Balance Sheets. On an aggregate basis as of June 30, 2019, the Registrants’ contract assets primarily relate to contracts in the Infrastructure Services segment where revenue is recognized using the input method. The Registrants’ contract liabilities are included in Accounts payable and Other current liabilities in their Condensed Consolidated Balance Sheets. On an aggregate basis as of June 30, 2019, the Registrants’ contract liabilities primarily relate to ESG contracts where revenue is recognized using the input method. The opening and closing balances of accounts receivable, other accrued unbilled revenue, contract assets and contract liabilities from contracts with customers for the six months ended June 30, 2019 are as follows: CenterPoint Energy Accounts Receivable Other Accrued Unbilled Revenues Contract Assets Contract Liabilities (in millions) Opening balance as of December 31, 2018 (1) $ 763 $ 575 $ 37 $ 47 Closing balance as of June 30, 2019 831 362 56 54 Increase (decrease) $ 68 $ (213 ) $ 19 $ 7 (1) Opening balances related to Vectren are as of February 1, 2019. The amount of revenue recognized in the six-month period ended June 30, 2019 that was included in the opening contract liability was $38 million . The difference between the opening and closing balances of the contract liabilities primarily results from the timing difference between CenterPoint Energy’s performance and the customer’s payment. Houston Electric Accounts Receivable Other Accrued Unbilled Revenues Contract Liabilities (in millions) Opening balance as of December 31, 2018 $ 234 $ 110 $ 3 Closing balance as of June 30, 2019 305 122 5 Increase $ 71 $ 12 $ 2 The amount of revenue recognized in the six-month period ended June 30, 2019 that was included in the opening contract liability was $2 million . The difference between the opening and closing balances of the contract liabilities primarily results from the timing difference between Houston Electric’s performance and the customer’s payment. CERC Accounts Receivable Other Accrued Unbilled Revenues (in millions) Opening balance as of December 31, 2018 $ 282 $ 263 Closing balance as of June 30, 2019 191 87 Decrease $ (91 ) $ (176 ) CERC does not have any opening or closing contract asset or contract liability balances. Remaining Performance Obligations (CenterPoint Energy). The table below discloses (1) the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for contracts and (2) when CenterPoint Energy expects to recognize this revenue. Such contracts include fixed price contracts in the Infrastructure Services reportable segment. Rolling 12 Months Thereafter Total (in millions) Revenue expected to be recognized on contracts in place as of June 30, 2019: Fixed price (bid) $ 317 $ — $ 317 $ 317 $ — $ 317 Practical Expedients and Exemption. Sales taxes and other similar taxes collected from customers are excluded from the transaction price. For contracts for which revenue from the satisfaction of the performance obligations is recognized in the amount invoiced, the practical expedient was elected and revenue expected to be recognized on these contracts has not been disclosed.

Employee Benefit Plans

Employee Benefit Plans	6 Months Ended
	Jun. 30, 2019
Retirement Benefits [Abstract]
Employee Benefit Plans [Text Block]	Employee Benefit Plans As a result of the Merger, CenterPoint Energy now maintains three additional qualified defined benefit pension plans which are closed to new participants, a non-qualified SERP and a postretirement benefit plan. The defined benefit pension plans cover eligible full-time regular employees of Vectren and are primarily non-contributory. The postretirement benefit plan provides health care and life insurance benefits to certain Vectren retirees, which are a combination of self-insured and fully insured programs, to eligible retirees on both a contributory and non-contributory basis. CenterPoint Energy, through its Infrastructure Services reportable segment, participates in several industry wide multi-employer pension plans for its collective bargaining employees which provide for monthly benefits based on length of service. The risks of participating in multi-employer pension plans are different from the risks of participating in single-employer pension plans in the following respects: (1) assets contributed to the multi-employer plan by one employer may be used to provide benefits to employees of other participating employers, (2) if a participating employer stops contributing to the plan, the unfunded obligations of the plan allocable to such withdrawing employer may be borne by the remaining participating employers and (3) if CenterPoint Energy stops participation in some of its multi-employer pension plans, CenterPoint Energy may be required to pay those plans an amount based on its allocable share of the underfunded status of the plan, referred to as a withdrawal liability. CenterPoint Energy, through Vectren, also acquired additional defined contribution retirement savings plans qualified under sections 401(a) and 401(k) of the Internal Revenue Code. The Registrants’ net periodic cost, before considering amounts subject to overhead allocations for capital expenditure projects or for amounts subject to deferral for regulatory purposes, includes the following components relating to pension and postretirement benefits: Pension Benefits (CenterPoint Energy) Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Service cost (1) $ 10 $ 9 $ 20 $ 18 Interest cost (2) 25 19 48 39 Expected return on plan assets (2) (27 ) (26 ) (52 ) (53 ) Amortization of prior service cost (2) 2 2 4 4 Amortization of net loss (2) 13 11 26 22 Settlement cost (3) 1 — 1 — Curtailment gain (4) — — (1 ) — Net periodic cost $ 24 $ 15 $ 46 $ 30 (1) Amounts presented in the table above are included in Operation and maintenance expense in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of amounts capitalized and regulatory deferrals. (2) Amounts presented in the table above are included in Other income (expense), net in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of regulatory deferrals. (3) A one-time, non-cash settlement cost is required when the total lump sum distributions or other settlements of plan benefit obligations during a plan year exceed the service cost and interest cost components of the net periodic cost for that year. In June 2019, CenterPoint Energy recognized a non-cash settlement cost of $1 million due to lump sum settlement payments from Vectren pension plans. (4) A curtailment gain or loss is required when the expected future services of a significant number of employees are reduced or eliminated for the accrual of benefits. In February 2019, CenterPoint Energy recognized a pension curtailment gain of $1 million related to Vectren employees whose employment was terminated after the Merger closed. Postretirement Benefits Three Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Service cost (1) $ — $ — $ 1 $ 1 $ — $ — Interest cost (2) 4 2 1 4 2 1 Expected return on plan assets (2) (1 ) (1 ) (1 ) (2 ) (1 ) (1 ) Amortization of prior service cost (credit) (2) (1 ) (2 ) — (1 ) (2 ) 1 Net periodic cost (income) $ 2 $ (1 ) $ 1 $ 2 $ (1 ) $ 1 Six Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Service cost (1) $ 1 $ — $ 1 $ 1 $ — $ — Interest cost (2) 8 4 2 7 4 2 Expected return on plan assets (2) (3 ) (2 ) (1 ) (3 ) (2 ) (1 ) Amortization of prior service cost (credit) (2) (2 ) (3 ) — (2 ) (3 ) 1 Net periodic cost (income) $ 4 $ (1 ) $ 2 $ 3 $ (1 ) $ 2 (1) Amounts presented in the tables above are included in Operation and maintenance expense in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of amounts capitalized and regulatory deferrals. (2) Amounts presented in the tables above are included in Other income (expense), net in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of regulatory deferrals. The table below reflects the expected contributions to be made to the pension and postretirement benefit plans during 2019: CenterPoint Energy Houston Electric CERC (in millions) Expected minimum contribution to pension plans during 2019 $ 94 $ — $ — Expected contribution to postretirement benefit plans in 2019 20 10 4 The table below reflects the contributions made to the pension and postretirement benefit plans during 2019: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Pension plans $ 27 $ — $ — $ 29 $ — $ — Postretirement benefit plans 3 2 1 8 5 2

Regulatory Accounting

Regulatory Accounting	6 Months Ended
	Jun. 30, 2019
Regulatory Assets and Liabilities, Other Disclosures [Abstract]
Regulatory Accounting [Text Block]	Regulatory Accounting The following is a list of regulatory assets and liabilities reflected on the Registrants’ respective Condensed Consolidated Balance Sheets: June 30, 2019 December 31, 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC Regulatory Assets: (in millions) Current regulatory assets (1) $ 20 $ — $ 20 $ 77 $ — $ 77 Non-current regulatory assets: Securitized regulatory assets 895 895 — 1,059 1,059 — Unrecognized equity return (2) (189 ) (189 ) — (213 ) (213 ) — Unamortized loss on reacquired debt (3) 65 65 — 68 68 — Pension and postretirement-related regulatory asset (3) 697 34 28 725 33 30 Hurricane Harvey restoration costs (3) 68 64 4 68 64 4 Regulatory assets related to TCJA (3) (4) 30 23 7 33 23 10 Asset retirement obligation (3) 140 25 90 109 24 85 Other regulatory assets-not earning a return (5) 133 74 28 81 55 26 Other regulatory assets 389 25 30 37 11 26 Total non-current regulatory assets 2,228 1,016 187 1,967 1,124 181 Total regulatory assets 2,248 1,016 207 2,044 1,124 258 Regulatory Liabilities: Current regulatory liabilities (6) 55 5 43 38 17 21 Non-current regulatory liabilities: Regulatory liabilities related to TCJA (4) 1,616 834 453 1,323 847 476 Estimated removal costs 1,415 271 629 886 269 617 Other regulatory liabilities 436 181 152 316 182 134 Total non-current regulatory liabilities 3,467 1,286 1,234 2,525 1,298 1,227 Total regulatory liabilities 3,522 1,291 1,277 2,563 1,315 1,248 Total regulatory assets and liabilities, net $ (1,274 ) $ (275 ) $ (1,070 ) $ (519 ) $ (191 ) $ (990 ) (1) Current regulatory assets are included in Prepaid expenses and other current assets in the Registrants’ respective Condensed Consolidated Balance Sheets. (2) The unrecognized equity return will be recognized as it is recovered in rates through 2024. The timing of CenterPoint Energy’s and Houston Electric’s recognition of the equity return will vary each period based on amounts actually collected during the period. The actual amounts recognized are adjusted at least annually to correct any over-collections or under-collections during the preceding 12 months. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric (in millions) Allowed equity return recognized $ 13 $ 13 $ 24 $ 24 $ 24 $ 24 $ 45 $ 45 (3) Substantially all of these regulatory assets are not earning a return. (4) The EDIT and deferred revenues will be recovered or refunded to customers as required by tax and regulatory authorities. (5) Regulatory assets acquired in the Merger and not earning a return were recorded at fair value as of the Merger Date. Such fair value adjustments are recognized over time until the regulatory asset is recovered. (6) Current regulatory liabilities are included in Other current liabilities in each of the Registrants’ respective Condensed Consolidated Balance Sheets.

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jun. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments [Text Block]	Derivative Instruments The Registrants are exposed to various market risks. These risks arise from transactions entered into in the normal course of business. The Registrants utilize derivative instruments such as physical forward contracts, swaps and options to mitigate the impact of changes in commodity prices, weather and interest rates on operating results and cash flows. (a) Non-Trading Activities Commodity Derivative Instruments (CenterPoint Energy and CERC). CenterPoint Energy, through its Indiana Utilities, and CERC, through CES, enter into certain derivative instruments to mitigate the effects of commodity price movements. Certain financial instruments used to hedge portions of the natural gas inventory of the Energy Services reportable segment are designated as fair value hedges for accounting purposes. Outstanding derivative instruments designated as economic hedges at the acquired Indiana Utilities hedge long-term variable rate natural gas purchases. The Indiana Utilities have authority to refund and recover mark-to-market gains and losses associated with hedging natural gas purchases, and thus the gains and losses on derivatives are deferred in a regulatory liability or asset. All other financial instruments do not qualify or are not designated as cash flow or fair value hedges. Interest Rate Risk Derivative Instruments. From time to time, the Registrants may enter into interest rate derivatives that are designated as economic or cash flow hedges. The objective of these hedges is to offset risk associated with interest rates borne by the Registrants in connection with an anticipated future fixed rate debt offering or other exposure to variable rate debt. The Indiana Utilities have authority to refund and recover mark-to-market gains and losses associated with hedging financing activity, and thus the gains and losses on derivatives are deferred in a regulatory liability or asset. For the impacts of cash flow hedges to Accumulated other comprehensive income, see Note 20 . The table below summarizes the Registrants’ outstanding interest rate hedging activity: June 30, 2019 December 31, 2018 Hedging Classification Notional Principal CenterPoint Energy (1) Houston Electric CenterPoint Energy Houston Electric (in millions) Economic hedge $ 84 $ — $ — $ — Cash flow hedge — — 450 450 (1) Relates to interest rate derivative instruments at SIGECO. Weather Hedges (CenterPoint Energy and CERC). CenterPoint Energy and CERC have weather normalization or other rate mechanisms that largely mitigate the impact of weather on NGD in Arkansas, Indiana, Louisiana, Mississippi, Minnesota, Ohio and Oklahoma, as applicable. CenterPoint Energy’s and CERC’s NGD in Texas and CenterPoint Energy’s electric operations in Texas and Indiana do not have such mechanisms, although fixed customer charges are historically higher in Texas for NGD compared to its other jurisdictions. As a result, fluctuations from normal weather may have a positive or negative effect on CenterPoint Energy’s and CERC’s NGD’s results in Texas and on CenterPoint Energy’s electric operations’ results in its Texas and Indiana service territories. CenterPoint Energy and CERC, as applicable, enter into winter season weather hedges from time to time for certain NGD jurisdictions and electric operations’ service territory to mitigate the effect of fluctuations from normal weather on results of operations and cash flows. These weather hedges are based on heating degree days at 10 -year normal weather. Houston Electric and Indiana Electric do not enter into weather hedges. The tables below summarize CenterPoint Energy’s and CERC’s current weather hedge gain (loss) activity: Three Months Ended June 30, 2019 2018 Texas Operations Winter Season Bilateral Cap CenterPoint Energy CERC Winter Season Bilateral Cap CenterPoint Energy CERC (in millions) NGD 2018 – 2019 $ 9 $ — $ — 2017 – 2018 $ 8 $ — $ — Electric operations 2018 – 2019 8 — — 2017 – 2018 9 — — Total (1) $ — $ — $ — $ — Six Months Ended June 30, 2019 2018 Texas Operations Winter Season Bilateral Cap CenterPoint Energy CERC Winter Season Bilateral Cap CenterPoint Energy CERC (in millions) NGD 2018 – 2019 $ 9 $ — $ — 2017 – 2018 $ 8 $ — $ — Electric operations 2018 – 2019 8 3 — 2017 – 2018 9 (4 ) — Total (1) $ 3 $ — $ (4 ) $ — (1) Weather hedge gains (losses) are recorded in Revenues in the Condensed Statements of Consolidated Income. (b) Derivative Fair Values and Income Statement Impacts The following tables present information about derivative instruments and hedging activities. The first three tables provide a balance sheet overview of Derivative Assets and Liabilities, while the last two tables provide a breakdown of the related income statement impacts. Fair Value of Derivative Instruments and Hedged Items CenterPoint Energy June 30, 2019 December 31, 2018 Balance Sheet Location Derivative Assets Fair Value Derivative Liabilities Fair Value Derivative Assets Fair Value Derivative Liabilities Fair Value (in millions) Derivatives designated as cash flow hedges: Interest rate derivatives Current Liabilities: Non-trading derivative liabilities $ — $ — $ — $ 24 Derivatives designated as fair value hedges: Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities 11 — 1 7 Derivatives not designated as hedging instruments: Natural gas derivatives (1) (2) (3) Current Assets: Non-trading derivative assets 103 2 103 3 Natural gas derivatives (1) (2) (3) Other Assets: Non-trading derivative assets 44 — 38 — Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities 74 148 62 173 Natural gas derivatives (1) (2) (3) Other Liabilities: Non-trading derivative liabilities 16 41 16 25 Interest rate derivatives Other Liabilities — 8 — — Indexed debt securities derivative Current Liabilities — 755 — 601 Total CenterPoint Energy $ 248 $ 954 $ 220 $ 833 (1) The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 2,186 Bcf or a net 355 Bcf long position and 1,674 Bcf or a net 140 Bcf long position as of June 30, 2019 and December 31, 2018 , respectively. Certain natural gas contracts hedge basis risk only and lack a fixed price exposure. (2) Natural gas contracts are presented on a net basis in CenterPoint Energy’s Condensed Consolidated Balance Sheets as they 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 CenterPoint Energy’s Condensed Consolidated Balance Sheets. The net of total non-trading natural gas derivative assets and liabilities is detailed in the Offsetting of Natural Gas Derivative Assets and Liabilities table below. (3) Derivative Assets and Derivative Liabilities include no material amounts related to physical forward transactions with Enable. Houston Electric June 30, 2019 December 31, 2018 Balance Sheet Location Derivative Assets Fair Value Derivative Liabilities Fair Value Derivative Assets Fair Value Derivative Liabilities Fair Value (in millions) Derivatives designated as cash flow hedges: Interest rate derivatives Current Liabilities: Non-trading derivative liabilities $ — $ — $ — $ 24 Total Houston Electric $ — $ — $ — $ 24 CERC June 30, 2019 December 31, 2018 Balance Sheet Location Derivative Assets Fair Value Derivative Liabilities Fair Value Derivative Assets Fair Value Derivative Liabilities Fair Value (in millions) Derivatives designated as fair value hedges: Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities $ 11 $ — $ 1 $ 7 Derivatives not designated as hedging instruments: Natural gas derivatives (1) (2) (3) Current Assets: Non-trading derivative assets 103 2 103 3 Natural gas derivatives (1) (2) (3) Other Assets: Non-trading derivative assets 44 — 38 — Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities 74 142 62 173 Natural gas derivatives (1) (2) (3) Other Liabilities: Non-trading derivative liabilities 16 30 16 25 Total CERC $ 248 $ 174 $ 220 $ 208 (1) The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 2,186 Bcf or a net 355 Bcf long position and 1,674 Bcf or a net 140 Bcf long position as of June 30, 2019 and December 31, 2018 , respectively. Certain natural gas contracts hedge basis risk only and lack a fixed price exposure. (2) Natural gas contracts are presented on a net basis in CERC’s Condensed Consolidated Balance Sheets as they 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 CERC’s Condensed Consolidated Balance Sheets. The net of total non-trading natural gas derivative assets and liabilities is detailed in the Offsetting of Natural Gas Derivative Assets and Liabilities table below. (3) Derivative Assets and Derivative Liabilities include no material amounts related to physical forward transactions with Enable. Cumulative Basis Adjustment for Fair Value Hedges (CenterPoint Energy and CERC) June 30, 2019 Balance Sheet Location Carrying Amount of Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Hedged items in fair value hedge relationship: Natural gas inventory Current Assets: Natural gas inventory $ 48 $ 48 $ (9 ) $ (9 ) Total $ 48 $ 48 $ (9 ) $ (9 ) December 31, 2018 Balance Sheet Location Carrying Amount of Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Hedged items in fair value hedge relationship: Natural gas inventory Current Assets: Natural gas inventory $ 57 $ 57 $ 1 $ 1 Total $ 57 $ 57 $ 1 $ 1 Offsetting of Natural Gas Derivative Assets and Liabilities (CenterPoint Energy and CERC) CenterPoint Energy June 30, 2019 December 31, 2018 Gross Amounts Recognized (1) Gross Amounts Offset in the Consolidated Balance Sheets Net Amount Presented in the Consolidated Balance Sheets (2) 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 $ 188 $ (87 ) $ 101 $ 166 $ (66 ) $ 100 Other Assets: Non-trading derivative assets 60 (16 ) 44 54 (16 ) 38 Current Liabilities: Non-trading derivative liabilities (149 ) 116 (33 ) (183 ) 81 (102 ) Other Liabilities: Non-trading derivative liabilities (41 ) 23 (18 ) (25 ) 20 (5 ) Total CenterPoint Energy $ 58 $ 36 $ 94 $ 12 $ 19 $ 31 CERC June 30, 2019 December 31, 2018 Gross Amounts Recognized (1) Gross Amounts Offset in the Consolidated Balance Sheets Net Amount Presented in the Consolidated Balance Sheets (2) 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 $ 188 $ (87 ) $ 101 $ 166 $ (66 ) $ 100 Other Assets: Non-trading derivative assets 60 (16 ) 44 54 (16 ) 38 Current Liabilities: Non-trading derivative liabilities (144 ) 116 (28 ) (183 ) 81 (102 ) Other Liabilities: Non-trading derivative liabilities (30 ) 23 (7 ) (25 ) 20 (5 ) Total CERC $ 74 $ 36 $ 110 $ 12 $ 19 $ 31 (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 Registrant’s respective Condensed 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 Hedge Accounting Activity (CenterPoint Energy and CERC) Three Months Ended June 30, 2019 2018 Location and Amount of Gain (Loss) recognized in Income on Hedging Relationship (1) Non-utility cost of revenues, including natural gas CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Total amounts presented in the statements of income in which the effects of hedges are recorded $ 910 $ 769 $ 790 $ 790 Gain (loss) on fair value hedging relationships: Commodity contracts: Hedged items - Natural gas inventory (4 ) (4 ) (12 ) (12 ) Derivatives designated as hedging instruments 4 4 12 12 Amounts excluded from effectiveness testing recognized in earnings immediately (65 ) (65 ) 69 69 Six Months Ended June 30, 2019 2018 Location and Amount of Gain (Loss) recognized in Income on Hedging Relationship (1) Non-utility cost of revenues, including natural gas CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Total amounts presented in the statements of income in which the effects of hedges are recorded $ 2,161 $ 1,940 $ 2,063 $ 2,063 Gain (loss) on fair value hedging relationships: Commodity contracts: Hedged items - Natural gas inventory (10 ) (10 ) (14 ) (14 ) Derivatives designated as hedging instruments 10 10 14 14 Amounts excluded from effectiveness testing recognized in earnings immediately (79 ) (79 ) (2 ) (2 ) (1) Income statement impact associated with cash flow hedge activity is related to gains and losses reclassified from Accumulated other comprehensive income into income. Amounts are immaterial for each Registrant in the three and six months ended June 30, 2019 and 2018, respectively. CenterPoint Energy Three Months Ended June 30, Six Months Ended June 30, Income Statement Location 2019 2018 2019 2018 (in millions) Effects of derivatives not designated as hedging instruments on the income statement: Commodity contracts Gains (losses) in Non-utility revenues $ 86 $ 11 $ 90 $ 68 Indexed debt securities derivative Loss on indexed debt securities (68 ) (254 ) (154 ) (272 ) Total CenterPoint Energy $ 18 $ (243 ) $ (64 ) $ (204 ) CERC Three Months Ended June 30, Six Months Ended June 30, Income Statement Location 2019 2018 2019 2018 (in millions) Effects of derivatives not designated as hedging instruments on the income statement: Commodity contracts Gains (losses) in Non-utility revenues $ 86 $ 11 $ 90 $ 68 Total CERC $ 86 $ 11 $ 90 $ 68 (c) Credit Risk Contingent Features (CenterPoint Energy and CERC) CenterPoint Energy and CERC enter into financial derivative contracts containing material adverse change provisions. These provisions could require CenterPoint Energy or CERC to post additional collateral if the S&P or Moody’s credit ratings of CenterPoint Energy, Inc. or its subsidiaries, including CERC Corp., are downgraded. June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Aggregate fair value of derivatives containing material adverse change provisions in a net liability position $ 1 $ 1 $ 1 $ 1 Fair value of collateral already posted — — — — Additional collateral required to be posted if credit risk contingent features triggered 1 1 — —

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements [Text Block]	Fair Value Measurements Assets and liabilities that are recorded at fair value in the Registrants’ 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, as well as natural gas inventory that has been designated as the hedged item in a fair value hedge. 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, quoted prices for identical or similar assets or liabilities in inactive markets, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means. 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 the Registrants’ Level 2 natural gas derivative assets or liabilities. CenterPoint Energy’s Level 2 indexed debt securities derivative is valued using an option model and a discounted cash flow model, which uses projected dividends on the ZENS-Related Securities and a discount rate as observable inputs. 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 the Registrants’ judgments about the assumptions market participants would use in pricing the asset or liability since limited market data exists. The Registrants develop these inputs based on the best information available, including the Registrants’ own data. A market approach is utilized to value the Registrants’ Level 3 assets or liabilities. As of June 30, 2019 , CenterPoint Energy’s and CERC’s Level 3 assets and liabilities are comprised of physical natural gas forward contracts and options. Level 3 physical natural gas forward contracts and options are valued using a discounted cash flow model which includes illiquid forward price curve locations (ranging from $1.62 to $5.64 per MMBtu for CenterPoint Energy and from $1.62 to $5.64 per MMBtu for CERC) as an unobservable input. CenterPoint Energy’s and CERC’s Level 3 physical natural gas forward contracts and options derivative assets and liabilities consist of both long and short positions (forwards and options). Forward price decreases (increases) as of June 30, 2019 would have resulted in lower (higher) values, respectively, for long forwards and options and higher (lower) values, respectively, for short forwards and options. The Registrants determine the appropriate level for each financial asset and liability on a quarterly basis. The Registrants also recognize 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 the Registrants’ assets and liabilities (including derivatives that are presented net) measured at fair value on a recurring basis as of June 30, 2019 and December 31, 2018 and indicate the fair value hierarchy of the valuation techniques utilized by the Registrants to determine such fair value. CenterPoint Energy June 30, 2019 December 31, 2018 Level 1 Level 2 Level 3 Netting (1) Total Level 1 Level 2 Level 3 Netting (1) Total Assets (in millions) Corporate equities $ 690 $ — $ — $ — $ 690 $ 542 $ — $ — $ — $ 542 Investments, including money market funds (2) 63 — — — 63 66 — — — 66 Natural gas derivatives (3)(4) — 215 33 (103 ) 145 — 173 47 (82 ) 138 Hedged portion of natural gas inventory — — — — — 1 — — — 1 Total assets $ 753 $ 215 $ 33 $ (103 ) $ 898 $ 609 $ 173 $ 47 $ (82 ) $ 747 Liabilities Indexed debt securities derivative $ — $ 755 $ — $ — $ 755 $ — $ 601 $ — $ — $ 601 Interest rate derivatives — 8 — — 8 24 — — — 24 Natural gas derivatives (3)(4) — 177 13 (139 ) 51 — 191 17 (101 ) 107 Hedged portion of natural gas inventory 9 — — — 9 — — — — — Total liabilities $ 9 $ 940 $ 13 $ (139 ) $ 823 $ 24 $ 792 $ 17 $ (101 ) $ 732 Houston Electric June 30, 2019 December 31, 2018 Level 1 Level 2 Level 3 Netting Total Level 1 Level 2 Level 3 Netting Total Assets (in millions) Investments, including money market funds (2) $ 47 $ — $ — $ — $ 47 $ 48 $ — $ — $ — $ 48 Total assets $ 47 $ — $ — $ — $ 47 $ 48 $ — $ — $ — $ 48 Liabilities Interest rate derivatives $ — $ — $ — $ — $ — $ 24 $ — $ — $ — $ 24 Total liabilities $ — $ — $ — $ — $ — $ 24 $ — $ — $ — $ 24 CERC June 30, 2019 December 31, 2018 Level 1 Level 2 Level 3 Netting (1) Total Level 1 Level 2 Level 3 Netting (1) Total Assets (in millions) Corporate equities $ 3 $ — $ — $ — $ 3 $ 2 $ — $ — $ — $ 2 Investments, including money market funds (2) 11 — — — 11 11 — — — 11 Natural gas derivatives (3)(4) — 215 33 (103 ) 145 — 173 47 (82 ) 138 Hedged portion of natural gas inventory — — — — — 1 — — — 1 Total assets $ 14 $ 215 $ 33 $ (103 ) $ 159 $ 14 $ 173 $ 47 $ (82 ) $ 152 Liabilities Natural gas derivatives (3)(4) $ — $ 161 $ 13 $ (139 ) $ 35 $ — $ 191 $ 17 $ (101 ) $ 107 Hedged portion of natural gas inventory 9 — — — 9 — — — — — Total liabilities $ 9 $ 161 $ 13 $ (139 ) $ 44 $ — $ 191 $ 17 $ (101 ) $ 107 (1) Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy and CERC to settle positive and negative positions and also include cash collateral posted with the same counterparties as follows: June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Cash collateral posted with the same counterparties $ 36 $ 36 $ 19 $ 19 (2) Amounts are included in Prepaid expenses and other current assets in the Condensed Consolidated Balance Sheets. (3) Natural gas derivatives include no material amounts related to physical forward transactions with Enable. (4) Level 1 natural gas derivatives include exchange-traded derivatives cleared by the CME, which deems that financial instruments cleared by the CME are settled daily in connection with posted cash payments. As a result of this exchange rule, CME-related derivatives are considered to have no fair value at the balance sheet date for financial reporting purposes and are presented in Level 1 net of posted cash; however, the derivatives remain outstanding and subject to future commodity price fluctuations until they are settled in accordance with their contractual terms. Derivative transactions cleared on exchanges other than the CME (e.g., the Intercontinental Exchange or ICE) continue to be reported on a gross basis. 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 and CERC have utilized Level 3 inputs to determine fair value: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy CERC CenterPoint Energy CERC CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Beginning balance $ 13 $ 13 $ (662 ) $ 12 $ 30 $ 30 $ (622 ) $ 46 Total gains (losses) 13 13 (11 ) 1 12 12 (16 ) 3 Total settlements (2 ) (2 ) 44 (1 ) (17 ) (17 ) 11 (35 ) Transfers into Level 3 (2 ) (2 ) 1 1 (1 ) (1 ) 1 1 Transfers out of Level 3 (2 ) (2 ) — — (4 ) (4 ) (2 ) (2 ) Ending balance (1) $ 20 $ 20 $ (628 ) $ 13 $ 20 $ 20 $ (628 ) $ 13 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: $ 9 $ 9 $ (9 ) $ 3 $ 6 $ 6 $ (23 ) $ (4 ) (1) CenterPoint Energy and CERC did not have significant Level 3 sales or purchases during the three or six months ended June 30, 2019 or 2018 . 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, CenterPoint Energy’s ZENS indexed debt securities derivative and hedging instruments 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 a combination of historical trading prices and comparable issue data. These liabilities, which are not measured at fair value in the Registrants’ Condensed Consolidated Balance Sheets, but for which the fair value is disclosed, would be classified as Level 2 in the fair value hierarchy. June 30, 2019 December 31, 2018 Carrying Amount Fair Value Carrying Amount Fair Value (in millions) CenterPoint Energy Long-term debt, including current maturities (1) $ 14,587 $ 15,438 $ 9,140 $ 9,308 Houston Electric Long-term debt, including current maturities (1) $ 5,165 $ 5,583 $ 4,717 $ 4,770 CERC Long-term debt, including current maturities $ 2,397 $ 2,641 $ 2,371 $ 2,488 (1) Includes Securitization Bonds debt.

Unconsolidated Affiliate (Cente

Unconsolidated Affiliate (CenterPoint Energy and CERC)	6 Months Ended
	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Unconsolidated Affiliate (CenterPoint Energy and CERC) [Text Block]	Unconsolidated Affiliates (CenterPoint Energy and CERC) CenterPoint Energy has the ability to significantly influence the operating and financial policies of Enable, a publicly traded MLP, and, accordingly, accounts for its investment in Enable’s common units using the equity method of accounting. 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. As of June 30, 2019, CenterPoint Energy’s maximum exposure to loss related to Enable is limited to its investment in unconsolidated affiliate, its investment in Enable Series A Preferred Units and outstanding current accounts receivable from Enable. Investment in Unconsolidated Affiliates (CenterPoint Energy): June 30, December 31, 2018 (in millions) Enable $ 2,469 $ 2,482 Other (1) 1 — Total $ 2,470 $ 2,482 (1) Represents the equity investment in ProLiance Holdings, LLC related primarily to an investment in LA Storage, LLC, a joint venture in a development project for salt-cavern natural gas storage, which was acquired in the Merger. This presentation reflects preliminary fair value of the equity investment and is subject to change. See Note 3. Limited Partner Interest and Units Held in Enable (CenterPoint Energy): June 30, 2019 Limited Partner Interest (1) Common Units (2) Enable Series A Preferred Units (3) CenterPoint Energy 53.8 % 233,856,623 14,520,000 OGE 25.5 % 110,982,805 — Public unitholders 20.7 % 90,233,873 — Total units outstanding 100.0 % 435,073,301 14,520,000 (1) Excludes the Enable Series A Preferred Units owned by CenterPoint Energy. (2) Held indirectly through CNP Midstream by CenterPoint Energy. (3) The carrying amount of the Enable Series A Preferred Units, reflected as Preferred units - unconsolidated affiliate on CenterPoint Energy’s Condensed Consolidated Balance Sheets, was $363 million as of June 30, 2019 and $363 million as of December 31, 2018 . No impairment charges or adjustment due to observable price changes were made during the current or prior reporting periods. Generally, sales to any person or entity (including a series of sales to the same person or entity) of more than 5% of the aggregate of the common units CenterPoint Energy owns in Enable or sales to any person or entity (including a series of sales to the same person or entity) by OGE of more than 5% of the aggregate of the common units it owns in Enable are subject to mutual rights of first offer and first refusal set forth in Enable’s Agreement of Limited Partnership. Interests Held in Enable GP (CenterPoint Energy): June 30, 2019 Management Rights (1) Incentive Distribution Rights (2) CenterPoint Energy (3) 50 % 40 % OGE 50 % 60 % (1) Enable is controlled jointly by CenterPoint Energy and OGE. Sale of CenterPoint Energy’s or OGE’s ownership interests in Enable GP to a third party is subject to mutual rights of first offer and first refusal, and CenterPoint Energy is not permitted to dispose of less than all of its interest in Enable GP. (2) Enable is expected to pay a minimum quarterly distribution of $0.2875 per common unit on its outstanding common units to the extent it has sufficient cash from operations after establishment of cash reserves and payment of fees and expenses, including payments to Enable GP and its affiliates, within 60 days after the end of each quarter. If cash distributions to Enable’s unitholders exceed $0.330625 per common unit in any quarter, Enable GP will receive increasing percentages or incentive distributions rights, up to 50% , of the cash Enable distributes in excess of that amount. In certain circumstances Enable GP will have the right to reset the minimum quarterly distribution and the target distribution levels at which the incentive distributions receive increasing percentages to higher levels based on Enable’s cash distributions at the time of the exercise of this reset election. To date, no incentive distributions have been made. (3) Held indirectly through CNP Midstream. Distributions Received from Enable (CenterPoint Energy and CERC): CenterPoint Energy Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Per Unit Cash Distribution Per Unit Cash Distribution Per Unit Cash Distribution Per Unit Cash Distribution (in millions, except per unit amounts) Enable common units (1) $ 0.3180 $ 75 $ 0.3180 $ 75 $ 0.6360 $ 149 $ 0.6360 $ 149 Enable Series A Preferred Units 0.6250 9 0.6250 9 1.2500 18 1.2500 18 Total CenterPoint Energy $ 84 $ 84 $ 167 $ 167 CERC Three Months Ended June 30, 2018 Six Months Ended June 30, 2018 Per Unit Cash Distribution Per Unit Cash Distribution Enable common units (1) $ 0.3180 $ 75 $ 0.6360 $ 149 Total CERC $ 75 $ 149 (1) Prior to the Internal Spin in September 2018, distributions from Enable were received by CERC. After such date, distributions from Enable were received by CenterPoint Energy. Transactions with Enable (CenterPoint Energy and CERC): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) CenterPoint Energy Natural gas expenses, including transportation and storage costs (1) $ 28 $ 29 $ 63 $ 66 Reimbursement of support services (2) 1 1 3 3 CERC Natural gas expenses, including transportation and storage costs (1) 28 29 63 66 Reimbursement of support services (2) 1 1 3 3 (1) Included in Non-utility costs of revenues, including natural gas on CenterPoint Energy’s and CERC’s respective Condensed Statements of Consolidated Income. (2) Represents amounts billed for certain support services provided to Enable. Actual support services costs are recorded net of reimbursement. June 30, December 31, 2018 (in millions) CenterPoint Energy Accounts payable for natural gas purchases from Enable $ 9 $ 11 Accounts receivable for amounts billed for services provided to Enable 3 2 CERC Accounts payable for natural gas purchases from Enable 9 11 Accounts receivable for amounts billed for services provided to Enable 3 2 CERC’s continuing involvement with Enable subsequent to the Internal Spin described below is limited to its natural gas purchases from Enable. Summarized unaudited consolidated income information for Enable is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Operating revenues $ 735 $ 805 $ 1,530 $ 1,553 Cost of sales, excluding depreciation and amortization 317 444 695 819 Depreciation and amortization 110 96 215 192 Operating income 167 126 332 265 Net income attributable to Enable common units 115 86 228 191 Reconciliation of Equity in Earnings (Losses), net: CenterPoint Energy’s interest $ 62 $ 46 $ 123 $ 103 Basis difference amortization (1) 12 12 24 24 Loss on dilution, net of proportional basis difference recognition — — (11 ) — CenterPoint Energy’s equity in earnings, net $ 74 $ 58 $ 136 $ 127 (1) Equity in earnings of unconsolidated affiliate includes CenterPoint Energy’s share of Enable earnings adjusted for the amortization of the basis difference of CenterPoint Energy’s original investment in Enable and its underlying equity in net assets of Enable. The basis difference is being amortized through the year 2048. Summarized unaudited consolidated balance sheet information for Enable is as follows: June 30, December 31, 2018 (in millions) Current assets $ 376 $ 449 Non-current assets 12,033 11,995 Current liabilities 1,270 1,615 Non-current liabilities 3,580 3,211 Non-controlling interest 37 38 Preferred equity 362 362 Accumulated other comprehensive loss (3 ) — Enable partners’ equity 7,163 7,218 Reconciliation of Investment in Enable: CenterPoint Energy’s ownership interest in Enable partners’ equity $ 3,850 $ 3,896 CenterPoint Energy’s basis difference (1,381 ) (1,414 ) CenterPoint Energy’s equity method investment in Enable $ 2,469 $ 2,482 Discontinued Operations (CERC): On September 4, 2018, CERC completed the Internal Spin. CERC executed the Internal Spin to, among other things, enhance the access of CERC and CenterPoint Energy to low cost debt and equity through increased transparency and understandability of the financial statements, improve CERC’s credit quality by eliminating the exposure to Enable’s midstream business and provide clarity of internal reporting and performance metrics to enhance management’s decision making for CERC and CNP Midstream. The Internal Spin represents a significant strategic shift that has a material effect on CERC’s operations and financial results and, as a result, CERC’s distribution of its equity investment in Enable met the criteria for discontinued operations classification. CERC has no continuing involvement in the equity investment of Enable. Therefore, CERC’s equity in earnings and related income taxes have been classified as Income from discontinued operations, net of tax, in CERC’s Condensed Statements of Consolidated Income for the periods presented. The following table presents amounts included in Income from discontinued operations, net of tax in CERC’s Condensed Statements of Consolidated Income. Three months ended June 30, 2018 Six months ended June 30, 2018 (in millions) Equity in earnings of unconsolidated affiliate, net $ 58 $ 127 Income tax expense 14 31 Income from discontinued operations, net of tax $ 44 $ 96

Goodwill and Other Intangibles

Goodwill and Other Intangibles (CenterPoint Energy and CERC)	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangibles (CenterPoint Energy and CERC) [Text Block]	Goodwill and Other Intangibles (CenterPoint Energy and CERC) CenterPoint Energy’s goodwill by reportable segment as of December 31, 2018 and changes in the carrying amount of goodwill as of June 30, 2019 is as follows: December 31, 2018 Additions (1) June 30, (in millions) Indiana Electric Integrated $ — $ 1,008 $ 1,008 Natural Gas Distribution 746 2,529 3,275 Energy Services (2) 110 — 110 Infrastructure Services — 355 355 Corporate and Other 11 420 431 Total $ 867 $ 4,312 $ 5,179 (1) CenterPoint Energy is currently assessing the allocation of goodwill to reportable segments subsequent to the Merger. See Note 3. (2) Amount presented is net of the accumulated goodwill impairment charge of $252 million recorded in 2012. CERC’s goodwill by reportable segment as of June 30, 2019 and December 31, 2018 is as follows: June 30, 2019 December 31, 2018 (in millions) Natural Gas Distribution $ 746 $ 746 Energy Services (1) 110 110 Corporate and Other 11 11 Total $ 867 $ 867 (1) Amount presented is net of the accumulated goodwill impairment charge of $252 million recorded in 2012. The tables below present information on CenterPoint Energy’s other intangible assets recorded in Intangible assets, net on CenterPoint Energy’s Condensed Consolidated Balance Sheets and the related amortization expense included in Depreciation and amortization on CenterPoint Energy’s Condensed Statements of Consolidated Income, unless otherwise indicated. June 30, 2019 December 31, 2018 Gross Carrying Amount Accumulated Amortization Net Balance Gross Carrying Amount Accumulated Amortization Net Balance (in millions) Customer relationships (1) $ 306 $ (36 ) $ 270 $ 86 $ (27 ) $ 59 Covenants not to compete 4 (3 ) 1 4 (3 ) 1 Trade names (1) 62 (3 ) 59 — — — Construction backlog (1) (2) 28 (11 ) 17 — — — Operation and maintenance agreements (1) (2) 12 (1 ) 11 — — — Other (1) 24 (12 ) 12 16 (11 ) 5 Total $ 436 $ (66 ) $ 370 $ 106 $ (41 ) $ 65 (1) The fair value of intangible assets acquired through acquisitions is preliminary and subject to change. See Note 3. (2) Amortization expense related to the operation and maintenance agreements and construction backlog is included in Non-utility cost of revenues, including natural gas on CenterPoint Energy’s Condensed Statements of Consolidated Income. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Amortization expense of intangible assets recorded in Depreciation and amortization (1) $ 7 $ 2 $ 13 $ 5 Amortization expense of intangible assets recorded in Non-utility cost of revenues, including natural gas (2) 3 — 12 — (1) Includes $5 million and $8 million for the three and six months ended June 30, 2019, respectively, of amortization expense related to intangibles acquired in the Merger. The fair value of intangible assets, and related amortization assumptions, acquired through acquisitions during the six months ended June 30, 2019, is preliminary and subject to change. See Note 3. (2) Includes a $4 million benefit related to a cumulative catch-up for remeasurement of the purchase price allocation for the three months ended June 30, 2019 related to the operation and maintenance agreements and construction backlog intangibles acquired in the Merger. The fair value of intangible assets, and related amortization assumptions, acquired through acquisitions during the six months ended June 30, 2019, is preliminary and subject to change. See Note 3. The tables below present information on CERC’s other intangible assets recorded in Other non-current assets on CERC’s Condensed Consolidated Balance Sheets and the related amortization expense included in Depreciation and amortization on CERC’s Condensed Statements of Consolidated Income. June 30, 2019 December 31, 2018 Gross Carrying Amount Accumulated Amortization Net Balance Gross Carrying Amount Accumulated Amortization Net Balance (in millions) Customer relationships $ 86 $ (30 ) $ 56 $ 86 $ (27 ) $ 59 Covenants not to compete 4 (3 ) 1 4 (3 ) 1 Other 16 (13 ) 3 16 (11 ) 5 Total $ 106 $ (46 ) $ 60 $ 106 $ (41 ) $ 65 Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Amortization expense of intangible assets recorded in Depreciation and amortization $ 2 $ 2 $ 5 $ 5 CenterPoint Energy and CERC estimate that amortization expense of intangible assets with finite lives for the next five years will be as follows: Amortization Expense CenterPoint Energy CERC (in millions) Remaining six months of 2019 $ 29 $ 6 2020 32 6 2021 31 6 2022 32 6 2023 31 5 2024 29 5

Indexed Debt Securities (ZENS)

Indexed Debt Securities (ZENS) and Securities Related to ZENS (CenterPoint Energy)	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Indexed Debt Securities (ZENS) and Securities Related to ZENS (CenterPoint Energy) [Text Block]	Indexed Debt Securities (ZENS) and Securities Related to ZENS (CenterPoint Energy) (a) Investment in Securities Related to ZENS A subsidiary of CenterPoint Energy holds shares of certain securities detailed in the table below, which are classified as trading securities and are expected to be held to facilitate CenterPoint Energy’s ability to meet its obligation under the ZENS. Unrealized gains and losses resulting from changes in the market value of the ZENS-Related Securities are recorded in CenterPoint Energy’s Condensed Statements of Consolidated Income. Shares Held June 30, 2019 December 31, 2018 AT&T Common 10,212,945 10,212,945 Charter Common 872,503 872,912 (b) ZENS In September 1999, CenterPoint Energy issued ZENS having an original principal amount of $1.0 billion of which $828 million remained outstanding as of June 30, 2019 . Each ZENS is exchangeable at the holder’s option at any time for an amount of cash equal to 95% of the market value of the reference shares attributable to such note. The number and identity of the reference shares attributable to each ZENS are adjusted for certain corporate events. CenterPoint Energy’s reference shares for each ZENS consisted of the following: June 30, 2019 December 31, 2018 (in shares) AT&T Common 0.7185 0.7185 Charter Common 0.061382 0.061382 CenterPoint Energy pays interest on the ZENS at an annual rate of 2% plus the amount of any quarterly cash dividends paid in respect of the ZENS-Related Securities. The principal amount of the ZENS is subject to increases or decreases to the extent that the annual yield from interest and cash dividends on the ZENS-Related Securities is less than or more than 2.309% . The adjusted principal amount is defined in the ZENS instrument as “contingent principal.” As of June 30, 2019 , the ZENS, having an original principal amount of $828 million and a contingent principal amount of $84 million , were outstanding and were exchangeable at the option of the holders for cash equal to 95% of the market value of the ZENS-Related Securities.

Short-Term Borrowings and Long-

Short-Term Borrowings and Long-term Debt	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Short-term Borrowings and Long-term Debt [Text Block]	Short-term Borrowings and Long-term Debt (a) Short-term Borrowings (CenterPoint Energy and CERC) Inventory Financing . NGD has AMAs associated with its utility distribution service in Arkansas, Louisiana, Mississippi, Oklahoma and Texas. The AMAs have varying terms, the longest of which expires in 2021. Pursuant to the provisions of the agreements, NGD sells natural gas and agrees to repurchase an equivalent amount of natural gas during the winter heating seasons at the same cost. These transactions are accounted for as an inventory financing. CenterPoint Energy and CERC had no outstanding obligations related to the AMAs as of both June 30, 2019 and December 31, 2018. (b) Long-term Debt Debt Transactions. During the six months ended June 30, 2019 , the following debt instruments were issued or incurred: Issuance Date Debt Instrument Aggregate Principal Amount Interest Rate as of June 30, 2019 Maturity Date (in millions) Houston Electric January 2019 General mortgage bonds $ 700 4.25 % 2049 CenterPoint Energy (1) February 2019 Variable rate term loan 25 3.14 % 2020 CenterPoint Energy May 2019 Variable rate term loan 1,000 3.17 % 2021 (1) Draw down by VCC on its variable rate term loan. Proceeds from Houston Electric’s debt issuance were used for general limited liability company purposes, including capital expenditures. Proceeds from VCC’s draw down of its term loan were used for general corporate purposes. Proceeds from CenterPoint Energy’s term loan were used for general corporate purposes, including the repayment of commercial paper. Acquired Debt (CenterPoint Energy). The table below summarizes the long-term external debt of Vectren and its subsidiaries that remained outstanding as of June 30, 2019: (in millions) Long-term debt: Senior notes due 2020 to 2045 (1) $ 637 Variable rate term loan due 2020 (2) 300 Variable rate term loan due 2020 (3) 200 First mortgage bonds due 2022 to 2055 (4) 293 Commercial paper (5) 297 Bank revolver (6) 135 Total Vectren debt $ 1,862 (1) Consists of $532 million of senior notes issued by VUHI, $96 million of senior notes issues by Indiana Gas, and $9 million of senior notes issued by VCC. The senior notes have stated interest rates that range from 3.33% to 7.08% . The senior notes issued by VUHI are guaranteed by SIGECO, Indiana Gas and VEDO. The senior notes issued by VCC are guaranteed by Vectren. In connection with the Merger, two of CenterPoint Energy’s acquired wholly-owned subsidiaries, VUHI and VCC, made offers to prepay certain outstanding guaranteed senior notes as required pursuant to certain note purchase agreements previously entered into by VUHI and VCC. In turn, VUHI and VCC borrowed $568 million and $191 million , respectively, from CenterPoint Energy to fund note redemptions effected pursuant to these prepayment offers. To fund these prepayments and payments of approximately $5 million of accrued interest, CenterPoint Energy issued approximately $764 million of commercial paper. (2) Issued by VUHI and guaranteed by SIGECO, Indiana Gas and VEDO. As of June 30, 2019, the term loan was fully drawn upon. The term loan’s interest rate is currently priced at one-month LIBOR, plus a credit spread ranging from 70 to 90 basis points depending on credit rating. (3) Issued by VCC and guaranteed by Vectren. As of June 30, 2019, the term loan was fully drawn upon, exclusive of any potential incremental term loans under the related facility’s accordion feature. The term loan’s interest rate is currently priced at one -month LIBOR, plus a credit spread of 70 basis points. (4) The first mortgage bonds issued by SIGECO subject SIGECO’s properties to a lien under the related mortgage indenture. The first mortgage bonds have stated interest rates that range from 2.375% to 6.72% . (5) Issued by VUHI with maturities up to 30 days. (6) Represents borrowings under the VCC credit facility, which is guaranteed by Vectren. Maturities (CenterPoint Energy). As of June 30, 2019 , maturities of CenterPoint Energy’s long-term debt were as follows: (in millions) Remaining six months of 2019 $ 216 2020 831 2021 2,761 2022 3,769 2023 713 2024 684 2025 and thereafter 5,752 Credit Facilities . The Registrants had the following revolving credit facilities as of June 30, 2019 : Execution Date Registrant Size of Facility Draw Rate of LIBOR plus (1) Financial Covenant Limit on Debt for Borrowed Money to Capital Ratio Debt for Borrowed Money to Capital Ratio as of June 30, 2019 (2) Termination Date (in millions) March 3, 2016 CenterPoint Energy $ 3,300 1.500% 65% (3) 58.1% March 3, 2022 July 14, 2017 CenterPoint Energy (4) 400 1.125% 65% 52.0% July 14, 2022 July 14, 2017 CenterPoint Energy (5) 200 1.250% 65% 58.0% July 14, 2022 March 3, 2016 Houston Electric 300 1.125% 65% (3) 49.4% March 3, 2022 March 3, 2016 CERC 900 1.250% 65% 46.5% March 3, 2022 Total $ 5,100 (1) Based on current credit ratings. (2) As defined in the revolving credit facility agreements, excluding Securitization Bonds. (3) For CenterPoint Energy and Houston Electric, the financial covenant limit will temporarily increase from 65% to 70% if Houston Electric experiences damage from a natural disaster in its service territory and CenterPoint Energy certifies to the administrative agent that Houston Electric has incurred system restoration costs reasonably likely to exceed $100 million in a consecutive 12 -month period, all or part of which Houston Electric 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. (4) This credit facility was issued by VUHI, is guaranteed by SIGECO, Indiana Gas and VEDO and includes a $10 million swing line sublimit and a $20 million letter of credit sublimit. This credit facility backstops VUHI’s commercial paper program. (5) This credit facility was issued by VCC, is guaranteed by Vectren and includes a $40 million swing line sublimit and an $80 million letter of credit sublimit. The Registrants, including the subsidiaries of CenterPoint Energy discussed above, were in compliance with all financial debt covenants as of June 30, 2019 . The table below reflects the utilization of the Registrants’ respective revolving credit facilities: June 30, 2019 December 31, 2018 Registrant Loans Letters Commercial Weighted Average Interest Rate Loans Letters Commercial Weighted Average Interest Rate (in millions, except weighted average interest rates) CenterPoint Energy (1) $ — $ 6 $ 2,078 2.63 % $ — $ 6 $ — — % CenterPoint Energy (2) — — 297 2.58 % — — — — CenterPoint Energy (3) 135 — — 3.65 % — — — — Houston Electric — 4 — — % — 4 — — CERC — 1 232 2.59 % — 1 210 2.93 % Total $ 135 $ 11 $ 2,607 $ — $ 11 $ 210 (1) CenterPoint Energy’s outstanding commercial paper generally has maturities of 60 days or less. Approximately $1.7 billion was issued to refinance commercial paper used to fund a portion of the cash consideration for the Merger, pay related fees and expenses, pay Vectren’s stub period cash dividend and long-term incentive payments and repay indebtedness of Vectren subsidiaries redeemed at the option of the holder as a result of the closing of the Merger. (2) This credit facility was issued by VUHI and is guaranteed by SIGECO, Indiana Gas and VEDO. (3) This credit facility was issued by VCC and is guaranteed by Vectren. Other. As of June 30, 2019 , certain financial institutions agreed to issue, from time to time, up to $50 million of letters of credit on behalf of Vectren and certain of its subsidiaries in exchange for customary fees. These agreements to issue letters of credit expire on December 31, 2019. As of June 30, 2019 , such financial institutions had issued $21 million of letters of credit on behalf of Vectren and certain of its subsidiaries. Houston Electric had issued $68 million and $68 million of general mortgage bonds as of June 30, 2019 and December 31, 2018

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes [Text Block]	Income Taxes The Registrants reported the following effective tax rates: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy (1) 13 % 15 % 12 % 27 % Houston Electric (2) 19 % 21 % 19 % 22 % CERC - Continuing operations (3) — % 33 % 14 % 19 % CERC - Discontinued operations (4) n/a 24 % n/a 24 % (1) CenterPoint Energy’s lower effective tax rate for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to the following: an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators in certain jurisdictions; the impact of state tax law changes that resulted in the remeasurement of state deferred taxes; and the release of a valuation allowance on certain state net operating losses that are now expected to be utilized prior to expiration due to a current period law change. (2) Houston Electric’s lower effective tax rate for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators. (3) CERC’s lower effective tax rate on income from continuing operations for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to the following: an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators in certain jurisdictions; the impact of state tax law changes that resulted in the remeasurement of state deferred taxes; and the release of a valuation allowance on certain state net operating losses that are now expected to be utilized prior to expiration due to a current period law change. The state law changes and valuation allowance release resulted in a lower than expected effective tax rate for the three months ended June 30, 2019 as compared to the three months ended June 30, 2018. (4) CERC’s effective tax rate on income from discontinued operations for the three and six months ended June 30, 2018 was a result of the 21% federal income tax rate plus allocable state income taxes. There are no comparable periods in 2019 since the Internal Spin was completed in the third quarter of 2018. The Registrants reported a net uncertain tax liability inclusive of interest and penalties of less than $1 million for the three months ended June 30, 2019, which reflects a release of approximately $1 million following the anticipated completion of Vectren’s 2016 IRS audit. No significant changes to the uncertain tax liability are expected over the next twelve months. For legacy CenterPoint Energy, tax years through 2016 have been audited and settled with the IRS; however, during 2018, CenterPoint Energy filed an amended 2014 tax return to claim additional tax credits that is currently under review by the IRS. For the 2017 – 2019 tax years, CenterPoint Energy is a participant in the IRS’s Compliance Assurance Process.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies [Text Block]	Commitments and Contingencies (a) Purchase Obligations (CenterPoint Energy and CERC) Commitments include minimum purchase obligations related to CenterPoint Energy’s and CERC’s Natural Gas Distribution and Energy Services reportable segments and CenterPoint Energy’s Indiana Electric Integrated reportable segment. Contracts with minimum payment provisions have various quantity requirements and durations and are not classified as non-trading derivative assets and liabilities in CenterPoint Energy’s and CERC’s Condensed Consolidated Balance Sheets as of June 30, 2019 and December 31, 2018 . These contracts meet an exception as “normal purchases contracts” or do not meet the definition of a derivative. Natural gas and coal supply commitments also include transportation contracts that do not meet the definition of a derivative. As of June 30, 2019 , minimum purchase obligations are approximately: CenterPoint Energy CERC (in millions) Remaining six months of 2019 $ 399 $ 276 2020 658 459 2021 488 308 2022 576 402 2023 350 197 2024 228 132 2025 and beyond 1,639 1,276 Indiana Electric Integrated also has other purchased power agreements that do not have minimum thresholds but do require payment when energy is generated by the provider. Costs arising from certain of these commitments are pass-through costs, generally collected dollar-for-dollar from retail customers through regulator-approved cost recovery mechanisms. (b) Guarantees and Product Warranties (CenterPoint Energy) In the normal course of business, ESG enters into contracts requiring it to timely install infrastructure, operate facilities, pay vendors and subcontractors and support warranty obligations and, at times, issue payment and performance bonds and other forms of assurance in connection with these contracts. Specific to ESG’s role as a general contractor in the performance contracting industry, as of June 30, 2019 , there were 68 open surety bonds supporting future performance with an aggregate face amount of approximately $705 million . ESG’s exposure is less than the face amount of the surety bonds and is limited to the level of uncompleted work under the contracts. As of June 30, 2019 , approximately 40% of the work was yet to be completed on projects with open surety bonds. Further, various subcontractors issue surety bonds to ESG. In addition to these performance obligations, ESG also warrants the functionality of certain installed infrastructure generally for one year and the associated energy savings over a specified number of years. Since ESG’s inception in 1994, CenterPoint Energy believes ESG has had a history of generally meeting its performance obligations and energy savings guarantees and its installed products operating effectively. CenterPoint Energy assessed the fair value of its obligation for such guarantees as of June 30, 2019 and no amounts were recorded on CenterPoint Energy’s Condensed Consolidated Balance Sheets. The Merger purchase price allocation, including the fair value of liabilities for guarantees on the Merger Date, remains preliminary. See Note 3. CenterPoint Energy issues parent company level guarantees to certain vendors, customers and other commercial counterparties of ESG. These guarantees do not represent incremental consolidated obligations, but rather, represent guarantees of subsidiary obligations to allow those subsidiaries to conduct business without posting other forms of assurance. As of June 30, 2019 , CenterPoint Energy, primarily through Vectren, has issued parent company level guarantees supporting ESG’s obligations. For those obligations where potential exposure can be estimated, management estimates the maximum exposure under these guarantees to be approximately $489 million as of June 30, 2019. This exposure primarily relates to energy savings guarantees on federal energy savings performance contracts. Other parent company level guarantees, certain of which do not contain a cap on potential liability, have been issued in support of federal operations and maintenance projects for which a maximum exposure cannot be estimated based on the nature of the projects. While there can be no assurance that performance under any of these parent company guarantees will not be required in the future, CenterPoint Energy considers the likelihood of a material amount being incurred as remote. (c) Legal, Environmental and Other Matters Legal Matters Gas Market Manipulation Cases (CenterPoint Energy and CERC) . CenterPoint Energy, its predecessor, Reliant Energy, and certain of their former subsidiaries were named as defendants in a large number of lawsuits 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 and its affiliates were released or dismissed from all such cases, except for one case pending in federal court in Nevada in which CES, a subsidiary of CERC, is a defendant. Plaintiffs in that case allege a conspiracy to inflate Wisconsin natural gas prices in 2000-2002. In May 2016, the district court granted CES’s motion for summary judgment, dismissing CES from the case. In August 2018, the Ninth Circuit Court of Appeals reversed that ruling, and CES requested further appellate review of that decision (which review has been stayed pending approval of the settlement agreement described below). Under a master separation agreement between CenterPoint Energy and a former subsidiary, 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. Through a series of transactions, RRI became known as GenOn and a wholly-owned subsidiary of NRG. None of those transactions alters GenOn’s contractual obligations to indemnify CenterPoint Energy and its subsidiaries for certain liabilities, including their indemnification obligations regarding the gas market manipulation litigation. In June 2017, however, GenOn and various affiliates filed for protection under Chapter 11 of the U.S. Bankruptcy Code. In December 2018, GenOn completed its reorganization and emerged from Chapter 11. CenterPoint Energy, CERC, and CES submitted proofs of claim in the bankruptcy proceedings to protect their indemnity rights. In October 2018, CES, GenOn, and the plaintiffs reached an agreement to settle all claims against CES and CES’s indemnity claims against GenOn, subject to approvals by the bankruptcy court and the federal district court. In January 2019, the bankruptcy court approved the settlement between CES and GenOn, and in August 2019, the federal district court issued final approval. CES will now complete the settlement payments, and the matter should be concluded later this year. This settlement did not have a material adverse effect on CenterPoint Energy’s or CERC’s financial condition, results of operations or cash flows. Minnehaha Academy (CenterPoint Energy and CERC). On August 2, 2017, a natural gas explosion occurred at the Minnehaha Academy in Minneapolis, Minnesota, resulting in the deaths of two school employees, serious injuries to others and significant property damage to the school. CenterPoint Energy, certain of its subsidiaries, including CERC, and the contractor company working in the school have been named in litigation arising out of this incident. CenterPoint Energy and CERC have reached confidential settlement agreements with some claimants. Additionally, CenterPoint Energy and CERC are cooperating with the ongoing investigation conducted by the National Transportation Safety Board. Further, CenterPoint Energy and CERC contested and have since reached a settlement regarding approximately $200,000 in fines imposed by the Minnesota Office of Pipeline Safety. In early 2018, the Minnesota Occupational Safety and Health Administration concluded its investigation without any adverse findings against CenterPoint Energy or CERC. CenterPoint Energy’s and CERC’s general and excess liability insurance policies provide coverage for third party bodily injury and property damage claims. Litigation Related to the Merger (CenterPoint Energy). With respect to the Merger, in July 2018, seven separate lawsuits were filed against Vectren and the individual directors of Vectren’s Board of Directors in the U.S. District Court for the Southern District of Indiana. These lawsuits allege violations of Sections 14(a) of the Exchange Act and SEC Rule 14a-9 on the grounds that the Vectren Proxy Statement filed on June 18, 2018 was materially incomplete because it omitted material information concerning the Merger. The lawsuits also seek certification as class actions. In August 2018, the seven lawsuits were consolidated, and the Court denied the plaintiffs’ request for a preliminary injunction. The plaintiffs filed their Consolidated Amended Class Action Complaint in October 2018, which the defendants have moved to dismiss and which motion remains pending. The plaintiffs filed their response in opposition to the motion to dismiss in January 2019, and Vectren filed its reply in support of the motion to dismiss in February 2019. In December 2018, two plaintiffs voluntarily dismissed their lawsuits, for which the Court entered an order approving the voluntary dismissal and dismissed without prejudice in January 2019. The defendants believe that the allegations asserted are without merit and intend to vigorously defend themselves against the claims raised. CenterPoint Energy does not expect the ultimate outcome of this matter to have a material adverse effect on its financial condition, results of operations or cash flows. Environmental Matters MGP Sites. CenterPoint Energy, CERC and their predecessors operated MGPs in the past. In addition, certain of CenterPoint Energy’s subsidiaries acquired through the Merger operated MGPs in the past. The costs CenterPoint Energy or CERC, as applicable, expect to incur to fulfill their respective obligations are estimated by management using assumptions based on actual costs incurred, the timing of expected future payments and inflation factors, among others. While CenterPoint Energy and CERC have recorded all costs which they presently expect to incur in connection with activities at these sites, it is possible that future events may require remedial activities which are not presently foreseen, and those costs may not be subject to PRP or insurance recovery. (i) Minnesota MGPs (CenterPoint Energy and CERC) . With respect to certain Minnesota MGP sites, CenterPoint Energy and CERC have completed state-ordered remediation and continue state-ordered monitoring and water treatment. CenterPoint Energy and CERC recorded a liability as reflected in the table below for continued monitoring and any future remediation required by regulators in Minnesota. The estimated range of possible remediation costs for the sites for which CenterPoint Energy and CERC believe they may have responsibility was based on remediation continuing for the time frame given in the table below. June 30, 2019 CenterPoint Energy CERC (in millions, except years) Amount accrued for remediation $ 7 $ 7 Minimum estimated remediation costs 4 4 Maximum estimated remediation costs 32 32 Minimum years of remediation 30 30 Maximum years of remediation 50 50 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 depend on the number of sites to be remediated, the participation of other PRPs, if any, and the remediation methods used. (ii) Indiana MGPs (CenterPoint Energy) . In the Indiana Gas service territory, the existence, location and certain general characteristics of 26 gas manufacturing and storage sites have been identified for which CenterPoint Energy may have some remedial responsibility. A remedial investigation/feasibility study was completed at one of the sites under an agreed upon order between Indiana Gas and the IDEM, and a Record of Decision was issued by the IDEM in January 2000. The remaining sites have been submitted to the IDEM’s VRP. CenterPoint Energy has also identified its involvement in five manufactured gas plant sites in SIGECO’s service territory, all of which are currently enrolled in the IDEM’s VRP. CenterPoint Energy is currently conducting some level of remedial activities, including groundwater monitoring at certain sites. As of June 30, 2019 , approximately $2 million of accrued costs related to these sites are included in Other liabilities on CenterPoint Energy’s Condensed Consolidated Balance Sheets. Total costs that may be incurred in connection with addressing these sites cannot be determined at this time. The estimated accrued costs are limited to CenterPoint Energy’s share of the remediation efforts and are therefore net of exposures of other PRPs. (iii) Other MGPs (CenterPoint Energy and CERC). In addition to the Minnesota and Indiana sites, the EPA and other regulators have investigated MGP sites that were owned or operated by CenterPoint Energy or CERC or may have been owned by one of their former affiliates. CenterPoint Energy and CERC do not expect the ultimate outcome of these matters to have a material adverse effect on the financial condition, results of operations or cash flows of either CenterPoint Energy or CERC. Asbestos. Some facilities owned by the Registrants or their predecessors contain or have contained asbestos insulation and other asbestos-containing materials. The Registrants are from time to time named, along with numerous others, as defendants in lawsuits filed by a number of individuals who claim injury due to exposure to asbestos, and the Registrants anticipate that additional claims may be asserted in the future. Although their ultimate outcome cannot be predicted at this time, the Registrants do not expect these matters, either individually or in the aggregate, to have a material adverse effect on their financial condition, results of operations or cash flows. CCR Rule (CenterPoint Energy). In April 2015, the EPA finalized its CCR Rule, which regulates ash as non-hazardous material under the RCRA. The final rule allows beneficial reuse of ash, and the majority of the ash generated by Indiana Electric’s generating plants will continue to be reused. In July 2018, the EPA released its final CCR Rule Phase I Reconsideration which extended the deadline to October 31, 2020 for ceasing placement of ash in ponds that exceed groundwater protections standards or that fail to meet location restrictions. While the EPA Phase I Reconsideration moves forward, the existing CCR compliance obligations remain in effect. Under the existing CCR Rule, Indiana Electric is required to perform integrity assessments, including ground water monitoring, at its F.B. Culley and A.B. Brown generating stations. The ground water studies are necessary to determine the remaining service life of the ponds and whether a pond must be retrofitted with liners or closed in place, with bottom ash handling conversions completed. Indiana Electric’s Warrick generating unit is not included in the scope of the CCR Rule as this unit has historically been part of a larger generating station that predominantly serves an adjacent industrial facility. In March 2018, Indiana Electric began posting ground water data monitoring reports annually to its public website in accordance with the requirements of the CCR Rule. This data preliminarily indicates potential groundwater impacts very close to Indiana Electric’s ash impoundments, and further analysis is ongoing. The CCR Rule required companies to complete location restriction determinations by October 18, 2018. Indiana Electric completed its evaluation and determined that one F.B. Culley pond and the A.B. Brown pond fail the aquifer placement location restriction. As a result of this failure, Indiana Electric is required to cease disposal of new ash in the ponds and commence closure of the ponds by October 31, 2020. CenterPoint Energy plans to seek extensions available under the CCR Rule that would allow Indiana Electric to continue to use the ponds through December 31, 2023. The inability to take these extensions may result in increased and potentially significant operational costs in connection with the accelerated implementation of an alternative ash disposal system or adversely impact Indiana Electric’s future operations. Failure to comply with these requirements could also result in an enforcement proceeding including the imposition of fines and penalties. On April 24, 2019, Indiana Electric received an order from the IURC approving recovery in rates of costs associated with the closure of one of the ponds at F.B. Culley. CenterPoint Energy believes the language in the IURC order is favorable for future recovery of closure costs for Indiana Electric’s remaining ponds. Indiana Electric continues to refine site specific estimates of closure costs. In March 2019, Indiana Electric entered into agreements with third parties for the excavation and beneficial reuse of the ash at the A.B. Brown ash pond. In July 2018, Indiana Electric filed a Complaint for Damages and Declaratory Relief against its insurers seeking reimbursement of defense, investigation and pond closure costs incurred to comply with the CCR Rule, and has since reached a confidential settlement agreement with one of the insurers. Any proceeds received will offset costs that have been and will be incurred to close the ponds. As of June 30, 2019 , CenterPoint Energy has recorded an approximate $ 90 million ARO, which represents the discounted value of future cash flow estimates to close the ponds at A.B. Brown and F.B. Culley. The fair value of the ARO assumed on the Merger Date is preliminary. This estimate is also subject to change in the near term due to the contractual arrangements; continued assessments of the ash, closure methods, and the timing of closure; implications of Indiana Electric’s generation transition plan; changing environmental regulations; and the anticipated outcome of the aforementioned insurance proceeding. In addition to these removal costs, Indiana Electric also anticipates equipment purchases of between $ 60 million and $ 80 million to complete the A.B. Brown closure project. Other Environmental. From time to time, the Registrants identify the presence of environmental contaminants during operations or on property where their predecessors have conducted operations. Other such sites involving contaminants may be identified in the future. The Registrants have and expect to continue to remediate any identified sites consistent with state and federal legal obligations. From time to time, the Registrants have received notices, and may receive notices in the future, from regulatory authorities or others regarding status as a PRP in connection with sites found to require remediation due to the presence of environmental contaminants. In addition, the Registrants have been, or may be, named from time to time as defendants in litigation related to such sites. Although the ultimate outcome of such matters cannot be predicted at this time, the Registrants do not expect these matters, either individually or in the aggregate, to have a material adverse effect on their financial condition, results of operations or cash flows. Other Proceedings The Registrants are 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, the Registrants are also defendants 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. The Registrants regularly analyze current information and, as necessary, provide accruals for probable and reasonably estimable liabilities on the eventual disposition of these matters. The Registrants do not expect the disposition of these matters to have a material adverse effect on the Registrants’ financial condition, results of operations or cash flows.

Earnings Per Share (CenterPoint

Earnings Per Share (CenterPoint Energy)	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Earnings Per Share (CenterPoint Energy) [Text Block]	Earnings Per Share (CenterPoint Energy) The following table reconciles numerators and denominators of CenterPoint Energy’s basic and diluted earnings per common share. Basic earnings per common share is determined by dividing Income available to common shareholders - basic by the Weighted average common shares outstanding - basic for the applicable period. Diluted earnings per common share is determined by the inclusion of potentially dilutive common stock equivalent shares that may occur if securities to issue Common Stock were exercised or converted into Common Stock. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions, except share and per share amounts) Numerator: Income (loss) available to common shareholders - basic $ 165 $ (75 ) $ 305 $ 90 Add back: Series B Preferred Stock dividend — — — — Income (loss) available to common shareholders - diluted $ 165 $ (75 ) $ 305 $ 90 Denominator: Weighted average common shares outstanding - basic 502,200,000 431,523,000 501,862,000 431,378,000 Plus: Incremental shares from assumed conversions: Restricted stock (1) 2,631,000 — 2,631,000 3,029,000 Series B Preferred Stock (2) — — — — Weighted average common shares outstanding - diluted 504,831,000 431,523,000 504,493,000 434,407,000 Earnings per common share: Basic earnings (loss) per common share $ 0.33 $ (0.17 ) $ 0.61 $ 0.21 Diluted earnings (loss) per common share $ 0.33 $ (0.17 ) $ 0.61 $ 0.21 (1) The potentially dilutive impact from restricted stock awards applies the treasury stock method. Under this method, an increase in the average fair market value of Common Stock can result in a greater dilutive impact from these securities. 3,029,000 incremental shares from assumed conversions of restricted stock have not been included in the computation of diluted earnings (loss) per share for the three months ended June 30, 2018, as their inclusion would be anti-dilutive. (2) The potentially dilutive impact from Series B Preferred Stock applies the if-converted method in calculating diluted earnings per common share. Under this method, diluted earnings per common share is adjusted for the more dilutive effect of the Series B Preferred Stock as a result of either its accumulated dividend for the period in the numerator or the assumed-converted common share equivalent in the denominator. The computation of diluted earnings per common share outstanding for the three and six months ended June 30, 2019 excludes 32,121,000 and 32,121,000 potentially dilutive shares, respectively, because to include them would be anti-dilutive. However, these shares could be potentially dilutive in the future.

Reportable Business Segments

Reportable Business Segments	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Reportable Business Segments [Text Block]	Reportable Segments The Registrants’ determination of reportable segments considers the strategic operating units under which the Registrants manage sales, allocate resources and assess performance of various products and services to wholesale or retail customers in differing regulatory environments. The Registrants use operating income as the measure of profit or loss for the reportable segments other than Midstream Investments, where equity in earnings is used. As of June 30, 2019 , reportable segments by Registrant were as follows: Registrants Houston Electric T&D Indiana Electric Integrated Natural Gas Distribution Energy Services Infrastructure Services Midstream Investments Corporate and Other CenterPoint Energy X X X X X X X Houston Electric X CERC X X X • The Houston Electric T&D reportable segment consists of electric transmission and distribution services in the Texas Gulf Coast area. • The Indiana Electric Integrated reportable segment consists of electric transmission and distribution services primarily to southwestern Indiana and includes power generation and wholesale power operations. • CenterPoint Energy’s Natural Gas Distribution reportable segment consists of intrastate natural gas sales to, and natural gas transportation and distribution for, residential, commercial, industrial and institutional customers in Arkansas, Indiana, Louisiana, Minnesota, Mississippi, Ohio, Oklahoma and Texas. • CERC’s Natural Gas Distribution reportable segment consists of intrastate natural gas sales to, and natural gas transportation and distribution for, residential, commercial, industrial and institutional customers in Arkansas, Louisiana, Minnesota, Mississippi, Oklahoma and Texas. • The Energy Services reportable segment consists of non-rate regulated natural gas sales and services operations. • The Infrastructure Services reportable segment consists of underground pipeline construction and repair services. • The Midstream Investments reportable segment consists of the equity investment in Enable (excluding the Enable Series A Preferred Units). • CenterPoint Energy’s Corporate and Other reportable segment consists of energy performance contracting and sustainable infrastructure services through ESG and other corporate operations which support all of the business operations of CenterPoint Energy. • CERC’s Corporate and Other reportable segment consists primarily of corporate operations which support all of the business operations of CERC. Financial data for reportable segments is as follows: CenterPoint Energy Three Months Ended June 30, 2019 2018 Revenues from Net Operating (Loss) Revenues from Net Operating (in millions) Houston Electric T&D $ 765 (1) $ — $ 169 $ 854 (1) $ — $ 181 Indiana Electric Integrated 140 — 25 — — — Natural Gas Distribution 650 10 47 487 8 7 Energy Services 838 17 29 841 19 15 Infrastructure Services 325 1 24 — — — Midstream Investments (2) — — — — — — Corporate and Other 80 — (7 ) 4 — (16 ) Eliminations — (28 ) — — (27 ) — Consolidated $ 2,798 $ — $ 287 $ 2,186 $ — $ 187 Six Months Ended June 30, 2019 2018 Revenues from External Customers Net Intersegment Revenues Operating Income (Loss) Revenues from External Customers Net Intersegment Revenues Operating (Loss) (in millions) Houston Electric T&D $ 1,454 (1) $ — $ 253 $ 1,605 (1) $ — $ 296 Indiana Electric Integrated 223 — 16 — — — Natural Gas Distribution 2,039 20 214 1,630 18 163 Energy Services 2,020 81 62 2,098 47 (11 ) Infrastructure Services 471 1 8 — — — Midstream Investments (2) — — — — — — Corporate and Other 122 — (21 ) 8 — (10 ) Eliminations — (102 ) — — (65 ) — Consolidated $ 6,329 $ — $ 532 $ 5,341 $ — $ 438 (1) Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113 (2) CenterPoint Energy’s Midstream Investments’ equity earnings, net are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Enable $ 74 $ 58 $ 136 $ 127 Houston Electric Houston Electric consists of a single reportable segment; therefore, a tabular reportable segment presentation has not been included. (1) Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113 CERC Three Months Ended June 30, 2019 2018 Revenues from Net Operating Revenues from Net Operating (in millions) Natural Gas Distribution $ 503 $ 10 $ 28 $ 487 $ 8 $ 7 Energy Services 839 16 29 841 19 15 Other Operations — — 1 — — — Eliminations — (26 ) — — (27 ) — Consolidated $ 1,342 $ — $ 58 $ 1,328 $ — $ 22 Six Months Ended June 30, 2019 2018 Revenues from External Customers Net Intersegment Revenues Operating Income (Loss) Revenues from External Customers Net Intersegment Revenues Operating Income (Loss) (in millions) Natural Gas Distribution $ 1,688 $ 20 $ 192 $ 1,630 $ 18 $ 163 Energy Services 2,021 80 62 2,098 47 (11 ) Corporate and Other 1 — — — — 1 Eliminations — (100 ) — — (65 ) — Consolidated $ 3,710 $ — $ 254 $ 3,728 $ — $ 153 CenterPoint Energy and CERC Total Assets June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint CERC (in millions) Houston Electric T&D $ 11,478 $ — $ 10,509 $ — Indiana Electric Integrated (1) 2,989 — — — Natural Gas Distribution (1) 12,946 6,843 6,956 6,956 Energy Services 1,262 1,262 1,558 1,558 Infrastructure Services (1) 1,303 — — — Midstream Investments 2,915 — 2,482 — Corporate and Other (1) 4,278 (2) 108 6,156 (2) 66 Eliminations (2,982 ) (398 ) (652 ) (366 ) Consolidated $ 34,189 $ 7,815 $ 27,009 $ 8,214 (1) Total assets by reportable segment include assets acquired in the Merger, which are based on preliminary estimates and allocations and are subject to change. See Note 3. (2) Includes pension and other postemployment-related regulatory assets of $639 million and $665 million , respectively, as of June 30, 2019 and December 31, 2018 . Additionally, total assets as of December 31, 2018 included $3.9 billion of temporary investments included in Cash and cash equivalents on CenterPoint Energy’s Consolidated Balance Sheets.

Supplemental Disclosure of Cash

Supplemental Disclosure of Cash Flow Information	6 Months Ended
	Jun. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Supplemental Disclosure of Cash Flow Information [Text Block]	Supplemental Disclosure of Cash Flow Information The table below provides supplemental disclosure of cash flow information: Six Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Cash Payments/Receipts: Interest, net of capitalized interest $ 231 $ 113 $ 55 $ 167 $ 90 $ 50 Income taxes (refunds), net 142 73 3 88 120 3 Non-cash transactions: Accounts payable related to capital expenditures 173 86 72 133 75 69 ROU assets obtained in exchange for lease liabilities (1) 42 1 28 — — — (1) Includes the transition impact of adoption of ASU 2016-02 Leases. The table below provides a reconciliation of cash, cash equivalents and restricted cash reported in the Condensed Consolidated Balance Sheets to the amount reported in the Condensed Statements of Consolidated Cash Flows: June 30, 2019 December 31, 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Cash and cash equivalents $ 271 $ 260 $ 1 $ 4,231 $ 335 $ 14 Restricted cash included in Prepaid expenses and other current assets 61 33 4 46 34 11 Restricted cash included in Other — — — 1 1 — Total cash, cash equivalents and restricted cash shown in Condensed Statements of Consolidated Cash Flows $ 332 $ 293 $ 5 $ 4,278 $ 370 $ 25

Related Party Transactions (Hou

Related Party Transactions (Houston Electric and CERC)	6 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Related Party Transactions (Houston Electric and CERC) [Text Block]	Related Party Transactions (Houston Electric and CERC) Houston Electric and CERC participate in a money pool through which they can borrow or invest on a short-term basis. Funding needs are aggregated and external borrowing or investing is based on the net cash position. The net funding requirements of the money pool are expected to be met with borrowings under CenterPoint Energy’s revolving credit facility or the sale of CenterPoint Energy’s commercial paper. The table below summarizes money pool activity: June 30, 2019 December 31, 2018 Houston Electric CERC Houston Electric CERC (in millions) Money pool investments (borrowings) (1) $ 794 $ 180 $ (1 ) $ 114 Weighted average interest rate 2.67 % 2.67 % 2.42 % 2.42 % (1) Included in Accounts and notes receivable (payable)–affiliated companies on Houston Electric’s and CERC’s respective Condensed Consolidated Balance Sheets. Houston Electric and CERC affiliate related net interest income (expense) were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Houston Electric CERC Houston Electric CERC Houston Electric CERC Houston Electric CERC (in millions) Interest income (expense) (1) $ 6 $ 1 $ — $ — $ 9 $ 2 $ — $ (2 ) (1) Interest income is included in Other income (expense), net and interest expense is included in Interest and other finance charges on Houston Electric’s and CERC’s respective Condensed Statements of Consolidated Income. CenterPoint Energy provides some corporate services to Houston Electric and CERC. The costs of services have been charged directly to Houston Electric and CERC using methods that management believes are reasonable. These methods include negotiated usage rates, dedicated asset assignment and proportionate corporate formulas based on operating expenses, assets, gross margin, employees and a composite of assets, gross margin and employees. Houston Electric provides certain services to CERC. These services are billed at actual cost, either directly or as an allocation and include fleet services, shop services, geographic services, surveying and right-of-way services, radio communications, data circuit management and field operations. Additionally, CERC provides certain services to Houston Electric. These services are billed at actual cost, either directly or as an allocation and include line locating and other miscellaneous services. These charges are not necessarily indicative of what would have been incurred had Houston Electric and CERC not been affiliates. Amounts charged for these services were as follows and are included primarily in operation and maintenance expenses: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Houston Electric CERC Houston Electric CERC Houston Electric CERC Houston Electric CERC (in millions) Corporate service charges $ 42 $ 32 $ 47 $ 35 $ 94 $ 75 $ 91 $ 69 Net affiliate service charges (billings) (2 ) 2 (3 ) 3 (4 ) 4 (5 ) 5 Infrastructure Services provides pipeline construction and repair services to CERC. Amounts charged for operation and maintenance expenses by Infrastructure Services to CERC were not significant from February 1, 2019 to June 30, 2019. Additionally, CERC, through CES, sells natural gas to Indiana Electric for use in electric generation activities. Amounts charged by CERC to Indiana Electric were not significant from February 1, 2019 to June 30, 2019. The table below presents transactions among Houston Electric, CERC and their parent, Utility Holding. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Houston Electric CERC Houston Electric CERC Houston Electric CERC Houston Electric CERC (in millions) Cash dividends paid to parent $ 16 $ 83 $ 31 $ 125 $ 40 $ 103 $ 63 $ 211 Cash contribution from parent — — — — 590 — — —

Leases (Notes)

Leases (Notes)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Leases [Text Block]	Leases The Registrants adopted ASC 842, Leases, and all related amendments on January 1, 2019 using the modified retrospective transition method and elected not to recast comparative periods in the year of adoption as permitted by the standard. There was no adjustment to retained earnings as a result of transition. As a result, disclosures for periods prior to adoption will be presented in accordance with accounting standards in effect for those periods. The Registrants also elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed them to carry forward the historical lease classification. Additionally, the Registrants elected the practical expedient related to land easements, which allows the carry forward of the accounting treatment for land easements on existing agreements. The total ROU assets obtained in exchange for new operating lease liabilities at transition were $30 million , $ 1 million and $ 27 million for CenterPoint Energy, Houston Electric and CERC, respectively. The Merger was completed on February 1, 2019, and as such the amounts are exclusive of Vectren’s leases. An arrangement is determined to be a lease at inception based on whether the Registrant has the right to control the use of an identified asset. ROU assets represent the Registrants’ right to use the underlying asset for the lease term and lease liabilities represent the Registrants’ obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term, including payments at commencement that depend on an index or rate. Most leases in which the Registrants are the lessee do not have a readily determinable implicit rate, so an incremental borrowing rate, based on the information available at the lease commencement date, is utilized to determine the present value of lease payments. When a secured borrowing rate is not readily available, unsecured borrowing rates are adjusted for the effects of collateral to determine the incremental borrowing rate. Each Registrant uses the implicit rate for agreements in which it is a lessor. Lease expense and lease income are recognized on a straight-line basis over the lease term for operating leases. The Registrants have lease agreements with lease and non-lease components and have elected the practical expedient to combine lease and non-lease components for certain classes of leases, such as office buildings. For classes of leases in which lease and non-lease components are not combined, consideration is allocated between components based on the stand-alone prices. Variable payments are not significant to the Registrants. The Registrants’ lease agreements do not contain any material residual value guarantees, material restrictions or material covenants. There are no material lease transactions with related parties. Agreements in which the Registrants are lessors do not include provisions for the lessee to purchase the assets. Because risk is minimal, the Registrants do not take any significant actions to manage risk associated with the residual value of their leased assets. The Registrants’ lease agreements are primarily equipment and real property leases, including land and office facility leases. The Registrants’ lease terms may include options to extend or terminate a lease when it is reasonably certain that those options will be exercised. The Registrants have elected an accounting policy that exempts leases with terms of one year or less from the recognition requirements of ASU 842. The components of lease cost, included in Operation and maintenance expense on the Registrants’ respective Condensed Statements of Consolidated Income, are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2019 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Operating lease cost $ 7 $ — $ 2 $ 11 $ — $ 3 Short-term lease cost 18 3 — 23 5 — Total lease cost $ 25 $ 3 $ 2 $ 34 $ 5 $ 3 Supplemental balance sheet information related to leases was as follows: June 30, 2019 CenterPoint Energy Houston Electric CERC (in millions, except lease term and discount rate) Assets: Operating ROU assets (1) $ 72 $ 1 $ 26 Total leased assets $ 72 $ 1 $ 26 Liabilities: Current operating lease liability (2) $ 22 $ — $ 5 Non-current operating lease liability (3) 50 1 21 Total leased liabilities $ 72 $ 1 $ 26 Weighted-average remaining lease term (in years) - operating leases 5.2 5.5 8.1 Weighted-average discount rate - operating leases 3.41 % 3.51 % 3.67 % (1) Reported within Other assets in the Condensed Consolidated Balance Sheets. (2) Reported within Current other liabilities in the Condensed Consolidated Balance Sheets. (3) Reported within Other liabilities in the Condensed Consolidated Balance Sheets. As of June 30, 2019 , maturities of operating lease liabilities were as follows: CenterPoint Energy Houston Electric CERC (in millions) Remaining six months of 2019 $ 14 $ — $ 3 2020 21 1 5 2021 15 — 4 2022 8 — 4 2023 7 — 3 2024 3 — 2 2025 and beyond 12 — 9 Total lease payments 80 1 30 Less: Interest 8 — 4 Present value of lease liabilities $ 72 $ 1 $ 26 The following table sets forth information concerning the Registrants’ obligations under non-cancelable long-term operating leases as of December 31, 2018: CenterPoint Energy Houston Electric CERC (in millions) 2019 $ 6 $ 1 $ 5 2020 6 — 5 2021 5 — 4 2022 4 — 4 2023 3 — 3 2024 and beyond 12 — 11 Total (1) $ 36 $ 1 $ 32 (1) The Merger was completed on February 1, 2019. As such, these amounts are exclusive of Vectren’s leases. As of June 30, 2019 , maturities of undiscounted operating lease payments to be received are as follows: CenterPoint Energy Houston Electric CERC (in millions) Remaining six months of 2019 $ 2 $ — $ — 2020 2 1 — 2021 2 — — 2022 2 — — 2023 2 — — 2024 2 — — 2025 and beyond 10 — — Total lease payments to be received $ 22 $ 1 $ — Other information related to leases is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2019 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Operating cash flows from operating leases included in the measurement of lease liabilities $ 7 $ — $ 1 $ 12 $ 1 $ 2

Equity

Equity	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Equity [Text Block]	Equity Dividends Declared and Paid (CenterPoint Energy) CenterPoint Energy paid dividends on its Common Stock during the six months ended June 30, 2019 and 2018 as presented in the table below: Declaration Date Record Date Payment Date Per Share Total (in millions) December 12, 2018 February 21, 2019 March 14, 2019 $ 0.2875 $ 144 April 25, 2019 May 16, 2019 June 13, 2019 0.2875 144 Total 2019 $ 0.5750 $ 288 December 13, 2017 February 15, 2018 March 8, 2018 $ 0.2775 $ 120 April 26, 2018 May 17, 2018 June 14, 2018 0.2775 120 Total 2018 $ 0.5550 $ 240 CenterPoint Energy declared no dividends on its Series A Preferred Stock or Series B Preferred Stock during the three or six months ended June 30, 2018. CenterPoint Energy paid dividends on its Series A Preferred Stock during the six months ended June 30, 2019 as presented in the table below: Declaration Date Record Date Payment Date Per Share Total (in millions) December 12, 2018 February 15, 2019 March 1, 2019 $ 32.1563 $ 26 Total 2019 $ 32.1563 $ 26 CenterPoint Energy paid dividends on its Series B Preferred Stock during the six months ended June 30, 2019 as presented in the table below: Declaration Date Record Date Payment Date Per Share Total (in millions) December 12, 2018 February 15, 2019 March 1, 2019 $ 17.5000 $ 17 April 25, 2019 May 15, 2019 June 3, 2019 17.5000 17 Total 2019 $ 35.0000 $ 34 Dividend Requirement on Preferred Stock (CenterPoint Energy) Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Series A Preferred Stock $ 13 $ — $ 25 $ — Series B Preferred Stock 17 — 34 — Total preferred stock dividend requirement $ 30 $ — $ 59 $ — Accumulated Other Comprehensive Income (Loss) Changes in accumulated comprehensive income (loss) are as follows: Three Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Beginning Balance $ (107 ) $ (15 ) $ 5 $ (63 ) $ 4 $ 6 Other comprehensive income (loss) before reclassifications: Deferred gain (loss) from interest rate derivatives (1) — — — (1 ) — — Amounts reclassified from accumulated other comprehensive loss: Prior service cost (2) 1 — — 1 — — Actuarial losses (2) 2 — — 1 — — Tax expense (1 ) — — — — — Net current period other comprehensive income 2 — — 1 — — Ending Balance $ (105 ) $ (15 ) $ 5 $ (62 ) $ 4 $ 6 Six Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Beginning Balance $ (108 ) $ (14 ) $ 5 $ (68 ) $ — $ 6 Other comprehensive income (loss) before reclassifications: Deferred gain (loss) from interest rate derivatives (1) (1 ) (1 ) — 4 5 — Amounts reclassified from accumulated other comprehensive loss: Prior service cost (2) 1 — — 1 — — Actuarial losses (2) 4 — — 3 — — Reclassification of deferred loss from cash flow hedges realized in net income 1 — — — — — Tax expense (2 ) — — (2 ) (1 ) — Net current period other comprehensive income (loss) 3 (1 ) — 6 4 — Ending Balance $ (105 ) $ (15 ) $ 5 $ (62 ) $ 4 $ 6 (1) Gains and losses are reclassified from Accumulated other comprehensive income into income when the hedged transactions affect earnings. The reclassification amounts are included in Interest and other finance charges in each of the Registrants’ respective Statements of Consolidated Income. Over the next twelve months estimated amortization from Accumulated Comprehensive Income into income is expected to be immaterial. (2) Amounts are included in the computation of net periodic cost and are reflected in Other income (expense), net in each of the Registrants’ respective Statements of Consolidated Income.

Subsequent Events (CenterPoint

Subsequent Events (CenterPoint Energy)	6 Months Ended
	Jun. 30, 2019
Subsequent Events [Abstract]
Subsequent Events (CenterPoint Energy) [Text Block]	Subsequent Events (CenterPoint Energy) CenterPoint Energy Dividend Declarations Equity Instrument Declaration Date Record Date Payment Date Per Share Common Stock July 31, 2019 August 15, 2019 September 12, 2019 $ 0.2875 Series A Preferred Stock July 31, 2019 August 15, 2019 September 3, 2019 30.6250 Series B Preferred Stock July 31, 2019 August 15, 2019 September 3, 2019 17.5000 Enable Distributions Declarations (CenterPoint Energy) Equity Instrument Declaration Date Record Date Payment Date Per Unit Distribution Expected Cash Distribution (in millions) Enable common units August 2, 2019 August 20, 2019 August 27, 2019 $ 0.3305 $ 77 Enable Series A Preferred Units August 2, 2019 August 2, 2019 August 14, 2019 0.6250 9

Background and Basis of Prese_2

Background and Basis of Presentation (Policies) - Vectren [Member]	6 Months Ended
	Jun. 30, 2019
Principles of Consolidation [Policy Text Block]	Principles of Consolidation . Businesses within the Infrastructure Services reportable segment provide underground pipeline construction and repair services for customers that include NGD utilities. In accordance with consolidation guidance in ASC 980—Regulated Operations, costs incurred by NGD utilities for these pipeline construction and repair services are not eliminated in consolidation when capitalized and included in rate base by the NGD utility.
Product Warranties, Performance Guarantees & Other Guarantees [Policy Text Block]	Guarantees . CenterPoint Energy recognizes guarantee obligations at fair value. CenterPoint Energy discloses parent company guarantees of a subsidiary’s obligation when that guarantee results in the exposure of a material obligation of the parent company even if the probability of fulfilling such obligation is considered remote. See Note 14 (b).
Income Taxes [Policy Text Block]	Income Taxes . Investment tax credits are deferred and amortized to income over the approximate lives of the related property.
MISO Transactions [Policy Text Block]	MISO Transactions . Indiana Electric is a member of MISO. MISO-related purchase and sale transactions are recorded using settlement information provided by the MISO. These purchase and sale transactions are accounted for on at least a net hourly position, meaning net purchases within that interval are recorded on CenterPoint Energy’s Condensed Statements of Consolidated Income in Utility natural gas, fuel and purchased power, and net sales within that interval are recorded on CenterPoint Energy’s Condensed Statements of Consolidated Income in Utility revenues. On occasion, prior period transactions are resettled outside the routine process due to a change in the MISO’s tariff or a material interpretation thereof. Expenses associated with resettlements are recorded once the resettlement is probable and the resettlement amount can be estimated. Revenues associated with resettlements are recognized when the amount is determinable and collectability is reasonably assured.

Leases (Policies)

Leases (Policies)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Lessee, Leases [Policy Text Block]	The Registrants adopted ASC 842, Leases, and all related amendments on January 1, 2019 using the modified retrospective transition method and elected not to recast comparative periods in the year of adoption as permitted by the standard. There was no adjustment to retained earnings as a result of transition. As a result, disclosures for periods prior to adoption will be presented in accordance with accounting standards in effect for those periods. The Registrants also elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed them to carry forward the historical lease classification. Additionally, the Registrants elected the practical expedient related to land easements, which allows the carry forward of the accounting treatment for land easements on existing agreements. The total ROU assets obtained in exchange for new operating lease liabilities at transition were $30 million , $ 1 million and $ 27 million for CenterPoint Energy, Houston Electric and CERC, respectively. The Merger was completed on February 1, 2019, and as such the amounts are exclusive of Vectren’s leases. An arrangement is determined to be a lease at inception based on whether the Registrant has the right to control the use of an identified asset. ROU assets represent the Registrants’ right to use the underlying asset for the lease term and lease liabilities represent the Registrants’ obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term, including payments at commencement that depend on an index or rate. Most leases in which the Registrants are the lessee do not have a readily determinable implicit rate, so an incremental borrowing rate, based on the information available at the lease commencement date, is utilized to determine the present value of lease payments. When a secured borrowing rate is not readily available, unsecured borrowing rates are adjusted for the effects of collateral to determine the incremental borrowing rate. Each Registrant uses the implicit rate for agreements in which it is a lessor. Lease expense and lease income are recognized on a straight-line basis over the lease term for operating leases. The Registrants have lease agreements with lease and non-lease components and have elected the practical expedient to combine lease and non-lease components for certain classes of leases, such as office buildings. For classes of leases in which lease and non-lease components are not combined, consideration is allocated between components based on the stand-alone prices. Variable payments are not significant to the Registrants. The Registrants’ lease agreements do not contain any material residual value guarantees, material restrictions or material covenants. There are no material lease transactions with related parties. Agreements in which the Registrants are lessors do not include provisions for the lessee to purchase the assets. Because risk is minimal, the Registrants do not take any significant actions to manage risk associated with the residual value of their leased assets. The Registrants’ lease agreements are primarily equipment and real property leases, including land and office facility leases. The Registrants’ lease terms may include options to extend or terminate a lease when it is reasonably certain that those options will be exercised. The Registrants have elected an accounting policy that exempts leases with terms of one year or less from the recognition requirements of ASU 842.

Mergers and Acquisitions (Cen_2

Mergers and Acquisitions (CenterPoint Energy) (Tables)	6 Months Ended
	Jun. 30, 2019
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	The Merger is being accounted for in accordance with ASC 805, Business Combinations, with CenterPoint Energy as the accounting acquirer of Vectren. Identifiable assets acquired and liabilities assumed have been recorded at their estimated fair values on the Merger Date. Vectren’s regulated operations, comprised of electric generation and electric and natural gas energy delivery services, are subject to the rate-setting authority of the FERC, the IURC and the PUCO, and are accounted for pursuant to U.S. generally accepted accounting principles for regulated operations. The rate-setting and cost-recovery provisions currently in place for Vectren’s regulated operations provide revenues derived from costs including a return on investment of assets and liabilities included in rate base. Thus, the fair values of Vectren’s tangible and intangible assets and liabilities subject to these rate-setting provisions approximate their carrying values. Accordingly, neither the assets and liabilities acquired, nor the unaudited pro forma financial information, reflect any adjustments related to these amounts. The fair value of regulatory assets not earning a return have been determined using the income approach and are considered Level 3 fair value measurements due to the use of significant judgmental and unobservable inputs. The fair value of Vectren’s assets acquired and liabilities assumed that are not subject to the rate-setting provisions, including identifiable intangibles, have been determined using the income approach and the market approach. The valuation of Vectren’s long-term debt is primarily considered a Level 2 fair value measurement. All other valuations are considered Level 3 fair value measurements due to the use of significant judgmental and unobservable inputs, including projected timing and amount of future cash flows and discount rates reflecting risk inherent in the future market prices. The following table presents the preliminary purchase price allocation as of June 30, 2019 (in millions): Cash and cash equivalents $ 16 Other current assets 598 Property, plant and equipment, net 5,146 Identifiable intangibles 322 Regulatory assets 338 Other assets 151 Total assets acquired 6,571 Current liabilities 690 Regulatory liabilities 944 Other liabilities 860 Long-term debt 2,401 Total liabilities assumed 4,895 Net assets acquired 1,676 Goodwill 4,306 Total purchase price consideration $ 5,982
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]	The estimated fair value of the identifiable intangible assets and related useful lives as included in the preliminary purchase price allocation include: Weighted Average Useful Lives Estimated Fair Value (in years) (in millions) Operation and maintenance agreements 24 $ 12 Customer relationships 18 220 Construction backlog 1 28 Trade names 10 62 Total $ 322
Business Combination, Separately Recognized Transactions [Table Text Block]	The results of operations for Vectren included in CenterPoint Energy’s Interim Condensed Financial Statements from the Merger Date are as follows: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (in millions) Operating revenues $ 688 $ 1,161 Net income 38 19
Business Acquisition, Pro Forma Information [Table Text Block]	The following unaudited pro forma financial information reflects the consolidated results of operations of CenterPoint Energy, assuming the Merger had taken place on January 1, 2018. The unaudited pro forma financial information has been presented for illustrative purposes only and is not necessarily indicative of the consolidated results of operations that would have been achieved had the Merger taken place on the dates indicated or of the future consolidated results of operations of the combined company. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Operating revenues $ 2,798 $ 2,830 $ 6,575 $ 6,644 Net income (loss) 199 (24 ) (1) 371 (2) 83 (3) (1) Pro forma net income was adjusted to exclude $10 million and $27 million , respectively, of Vectren and CenterPoint Energy Merger-related transaction costs incurred in 2018 and reflected in the historical income statements. (2) Pro forma net income was adjusted to exclude $37 million of Vectren Merger-related transaction costs incurred in 2019. (3) Pro forma net income was adjusted to include $46 million and $1 million , respectively, of Vectren and CenterPoint Energy Merger-related transaction costs incurred from July 1, 2018 to June 30, 2019.

New Accounting Pronouncements (

New Accounting Pronouncements (Tables)	6 Months Ended
	Jun. 30, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The following table provides an overview of certain 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 2016-02- Leases (Topic 842) and related amendments 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 January 1, 2019 The Registrants adopted the standard and recognized a right-of-use asset and lease liability on their statement of financial position with no material impact on their results of operations and cash flows. See Note 19 for more information. Issued, Not Yet Effective Accounting Standards ASU Number and Name Description Effective Date Financial Statement Impact upon Adoption ASU 2016-13- Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments This standard, including standards amending this standard, requires a new model called CECL to estimate credit losses for (1) financial assets subject to credit losses and measured at amortized cost and (2) certain off-balance sheet credit exposures. Upon initial recognition of the exposure, the CECL model requires an entity to estimate the credit losses expected over the life of an exposure based on historical information, current information and reasonable and supportable forecasts, including estimates of prepayments. Transition method : modified retrospective January 1, 2020 Early adoption is permitted The Registrants are currently assessing the impact that this standard will have on their financial position, results of operations, cash flows and disclosures. ASU 2018-13- Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement This standard eliminates, modifies and adds certain disclosure requirements for fair value measurements. Transition method : prospective for additions and one modification and retrospective for all other amendments Adoption of eliminations and modifications as of September 30, 2018; Additions will be adopted January 1, 2020 The adoption of this standard did not impact the Registrants’ financial position, results of operations or cash flows. Note 8 reflects the disclosures modified upon adoption. ASU 2018-15- Intangibles-Goodwill and Other- Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract This standard aligns accounting for implementation costs incurred in a cloud computing arrangement that is accounted for as a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The update also prescribes the balance sheet, income statement, and cash flow classification of the capitalized implementation costs and related amortization expense and requires additional quantitative and qualitative disclosures. Transition method : retrospective or prospective January 1, 2020 Early adoption is permitted The adoption of this standard will allow the Registrants to capitalize certain implementation costs incurred in cloud computing arrangements that are accounted for as service contracts. 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.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue [Table Text Block]	The following tables disaggregate revenues by reportable segment and major source: CenterPoint Energy Three Months Ended June 30, 2019 Houston Electric T&D (1) Indiana Electric Integrated (1) Natural Gas Distribution (1) Energy Infrastructure Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 768 $ 140 $ 657 $ 87 $ 326 $ 78 $ 2,056 Derivatives income — — — 768 — — 768 Other (3) (3 ) — 3 — — 2 2 Eliminations — — (10 ) (17 ) (1 ) — (28 ) Total revenues $ 765 $ 140 $ 650 $ 838 $ 325 $ 80 $ 2,798 Six Months Ended June 30, 2019 Houston Electric T&D (1) Indiana Electric Integrated (1) (4) Natural Gas Distribution (1) (4) Energy Infrastructure Services (2) (4) Corporate and Other (2) (4) Total (in millions) Revenue from contracts $ 1,458 $ 223 $ 2,063 $ 260 $ 472 $ 119 $ 4,595 Derivatives income 3 — — 1,841 — — 1,844 Other (3) (7 ) — (4 ) — — 3 (8 ) Eliminations — — (20 ) (81 ) (1 ) — (102 ) Total revenues $ 1,454 $ 223 $ 2,039 $ 2,020 $ 471 $ 122 $ 6,329 Three Months Ended June 30, 2018 Houston Electric T&D (1) Indiana Natural Gas Distribution (1) Energy Infrastructure Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 860 $ — $ 509 $ 78 $ — $ 2 $ 1,449 Derivatives income — — — 782 — — 782 Other (3) (6 ) — (14 ) — — 2 (18 ) Eliminations — — (8 ) (19 ) — — (27 ) Total revenues $ 854 $ — $ 487 $ 841 $ — $ 4 $ 2,186 Six Months Ended June 30, 2018 Houston Electric T&D (1) Indiana Natural Gas Distribution (1) Energy Infrastructure Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 1,621 $ — $ 1,695 $ 256 $ — $ 3 $ 3,575 Derivatives income (4 ) — — 1,889 — — 1,885 Other (3) (12 ) — (47 ) — — 5 (54 ) Eliminations — — (18 ) (47 ) — — (65 ) Total revenues $ 1,605 $ — $ 1,630 $ 2,098 $ — $ 8 $ 5,341 (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. (4) Reflects revenues from Vectren subsidiaries for the period from February 1, 2019 to June 30, 2019. Houston Electric Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Revenue from contracts $ 768 $ 860 $ 1,458 $ 1,621 Other (1) (3 ) (6 ) (7 ) (12 ) Total revenues $ 765 $ 854 $ 1,451 $ 1,609 (1) 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. CERC Three Months Ended June 30, 2019 2018 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 $ 510 $ 87 $ — $ 597 $ 509 $ 78 $ — $ 587 Derivatives income — 768 — 768 — 782 — 782 Other (3) 3 — — 3 (14 ) — — (14 ) Eliminations (10 ) (16 ) — (26 ) (8 ) (19 ) — (27 ) Total revenues $ 503 $ 839 $ — $ 1,342 $ 487 $ 841 $ — $ 1,328 Six Months Ended June 30, 2019 2018 Natural Gas Distribution (1) Energy Services (2) Corporate and Other (2) Total Natural Gas Distribution (1) Energy Services (2) Corporate and Other (2) Total (in millions) Revenue from contracts $ 1,708 $ 260 $ 1 $ 1,969 $ 1,695 $ 256 $ — $ 1,951 Derivatives income — 1,841 — 1,841 — 1,889 — 1,889 Other (3) — — — — (47 ) — — (47 ) Eliminations (20 ) (80 ) — (100 ) (18 ) (47 ) — (65 ) Total revenues $ 1,688 $ 2,021 $ 1 $ 3,710 $ 1,630 $ 2,098 $ — $ 3,728 (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.
Contract with Customer, Asset and Liability [Table Text Block]	The opening and closing balances of accounts receivable, other accrued unbilled revenue, contract assets and contract liabilities from contracts with customers for the six months ended June 30, 2019 are as follows: CenterPoint Energy Accounts Receivable Other Accrued Unbilled Revenues Contract Assets Contract Liabilities (in millions) Opening balance as of December 31, 2018 (1) $ 763 $ 575 $ 37 $ 47 Closing balance as of June 30, 2019 831 362 56 54 Increase (decrease) $ 68 $ (213 ) $ 19 $ 7 (1) Opening balances related to Vectren are as of February 1, 2019. The amount of revenue recognized in the six-month period ended June 30, 2019 that was included in the opening contract liability was $38 million . The difference between the opening and closing balances of the contract liabilities primarily results from the timing difference between CenterPoint Energy’s performance and the customer’s payment. Houston Electric Accounts Receivable Other Accrued Unbilled Revenues Contract Liabilities (in millions) Opening balance as of December 31, 2018 $ 234 $ 110 $ 3 Closing balance as of June 30, 2019 305 122 5 Increase $ 71 $ 12 $ 2 The amount of revenue recognized in the six-month period ended June 30, 2019 that was included in the opening contract liability was $2 million . The difference between the opening and closing balances of the contract liabilities primarily results from the timing difference between Houston Electric’s performance and the customer’s payment. CERC Accounts Receivable Other Accrued Unbilled Revenues (in millions) Opening balance as of December 31, 2018 $ 282 $ 263 Closing balance as of June 30, 2019 191 87 Decrease $ (91 ) $ (176 ) CERC does not have any opening or closing contract asset or contract liability balances.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	Remaining Performance Obligations (CenterPoint Energy). The table below discloses (1) the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period for contracts and (2) when CenterPoint Energy expects to recognize this revenue. Such contracts include fixed price contracts in the Infrastructure Services reportable segment. Rolling 12 Months Thereafter Total (in millions) Revenue expected to be recognized on contracts in place as of June 30, 2019: Fixed price (bid) $ 317 $ — $ 317 $ 317 $ — $ 317

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2019
Retirement Benefits [Abstract]
Schedule of Defined Benefit Plans Disclosures [Table Text Block]	The Registrants’ net periodic cost, before considering amounts subject to overhead allocations for capital expenditure projects or for amounts subject to deferral for regulatory purposes, includes the following components relating to pension and postretirement benefits: Pension Benefits (CenterPoint Energy) Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Service cost (1) $ 10 $ 9 $ 20 $ 18 Interest cost (2) 25 19 48 39 Expected return on plan assets (2) (27 ) (26 ) (52 ) (53 ) Amortization of prior service cost (2) 2 2 4 4 Amortization of net loss (2) 13 11 26 22 Settlement cost (3) 1 — 1 — Curtailment gain (4) — — (1 ) — Net periodic cost $ 24 $ 15 $ 46 $ 30 (1) Amounts presented in the table above are included in Operation and maintenance expense in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of amounts capitalized and regulatory deferrals. (2) Amounts presented in the table above are included in Other income (expense), net in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of regulatory deferrals. (3) A one-time, non-cash settlement cost is required when the total lump sum distributions or other settlements of plan benefit obligations during a plan year exceed the service cost and interest cost components of the net periodic cost for that year. In June 2019, CenterPoint Energy recognized a non-cash settlement cost of $1 million due to lump sum settlement payments from Vectren pension plans. (4) A curtailment gain or loss is required when the expected future services of a significant number of employees are reduced or eliminated for the accrual of benefits. In February 2019, CenterPoint Energy recognized a pension curtailment gain of $1 million related to Vectren employees whose employment was terminated after the Merger closed. Postretirement Benefits Three Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Service cost (1) $ — $ — $ 1 $ 1 $ — $ — Interest cost (2) 4 2 1 4 2 1 Expected return on plan assets (2) (1 ) (1 ) (1 ) (2 ) (1 ) (1 ) Amortization of prior service cost (credit) (2) (1 ) (2 ) — (1 ) (2 ) 1 Net periodic cost (income) $ 2 $ (1 ) $ 1 $ 2 $ (1 ) $ 1 Six Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Service cost (1) $ 1 $ — $ 1 $ 1 $ — $ — Interest cost (2) 8 4 2 7 4 2 Expected return on plan assets (2) (3 ) (2 ) (1 ) (3 ) (2 ) (1 ) Amortization of prior service cost (credit) (2) (2 ) (3 ) — (2 ) (3 ) 1 Net periodic cost (income) $ 4 $ (1 ) $ 2 $ 3 $ (1 ) $ 2 (1) Amounts presented in the tables above are included in Operation and maintenance expense in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of amounts capitalized and regulatory deferrals. (2) Amounts presented in the tables above are included in Other income (expense), net in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of regulatory deferrals.
Benefit Plan Contributions [Table Text Block]	The table below reflects the expected contributions to be made to the pension and postretirement benefit plans during 2019: CenterPoint Energy Houston Electric CERC (in millions) Expected minimum contribution to pension plans during 2019 $ 94 $ — $ — Expected contribution to postretirement benefit plans in 2019 20 10 4 The table below reflects the contributions made to the pension and postretirement benefit plans during 2019: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Pension plans $ 27 $ — $ — $ 29 $ — $ — Postretirement benefit plans 3 2 1 8 5 2

Regulatory Accounting (Tables)

Regulatory Accounting (Tables)	6 Months Ended
	Jun. 30, 2019
Regulatory Assets and Liabilities, Other Disclosures [Abstract]
Schedule of Regulatory Assets and Liabilities [Table Text Block]	The following is a list of regulatory assets and liabilities reflected on the Registrants’ respective Condensed Consolidated Balance Sheets: June 30, 2019 December 31, 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC Regulatory Assets: (in millions) Current regulatory assets (1) $ 20 $ — $ 20 $ 77 $ — $ 77 Non-current regulatory assets: Securitized regulatory assets 895 895 — 1,059 1,059 — Unrecognized equity return (2) (189 ) (189 ) — (213 ) (213 ) — Unamortized loss on reacquired debt (3) 65 65 — 68 68 — Pension and postretirement-related regulatory asset (3) 697 34 28 725 33 30 Hurricane Harvey restoration costs (3) 68 64 4 68 64 4 Regulatory assets related to TCJA (3) (4) 30 23 7 33 23 10 Asset retirement obligation (3) 140 25 90 109 24 85 Other regulatory assets-not earning a return (5) 133 74 28 81 55 26 Other regulatory assets 389 25 30 37 11 26 Total non-current regulatory assets 2,228 1,016 187 1,967 1,124 181 Total regulatory assets 2,248 1,016 207 2,044 1,124 258 Regulatory Liabilities: Current regulatory liabilities (6) 55 5 43 38 17 21 Non-current regulatory liabilities: Regulatory liabilities related to TCJA (4) 1,616 834 453 1,323 847 476 Estimated removal costs 1,415 271 629 886 269 617 Other regulatory liabilities 436 181 152 316 182 134 Total non-current regulatory liabilities 3,467 1,286 1,234 2,525 1,298 1,227 Total regulatory liabilities 3,522 1,291 1,277 2,563 1,315 1,248 Total regulatory assets and liabilities, net $ (1,274 ) $ (275 ) $ (1,070 ) $ (519 ) $ (191 ) $ (990 ) (1) Current regulatory assets are included in Prepaid expenses and other current assets in the Registrants’ respective Condensed Consolidated Balance Sheets. (2) The unrecognized equity return will be recognized as it is recovered in rates through 2024. The timing of CenterPoint Energy’s and Houston Electric’s recognition of the equity return will vary each period based on amounts actually collected during the period. The actual amounts recognized are adjusted at least annually to correct any over-collections or under-collections during the preceding 12 months. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric (in millions) Allowed equity return recognized $ 13 $ 13 $ 24 $ 24 $ 24 $ 24 $ 45 $ 45 (3) Substantially all of these regulatory assets are not earning a return. (4) The EDIT and deferred revenues will be recovered or refunded to customers as required by tax and regulatory authorities. (5) Regulatory assets acquired in the Merger and not earning a return were recorded at fair value as of the Merger Date. Such fair value adjustments are recognized over time until the regulatory asset is recovered. (6) Current regulatory liabilities are included in Other current liabilities in each of the Registrants’ respective Condensed Consolidated Balance Sheets.
Amount_Allowed_equity_return_recognized_in_period [Table Text Block]	The unrecognized equity return will be recognized as it is recovered in rates through 2024. The timing of CenterPoint Energy’s and Houston Electric’s recognition of the equity return will vary each period based on amounts actually collected during the period. The actual amounts recognized are adjusted at least annually to correct any over-collections or under-collections during the preceding 12 months. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric (in millions) Allowed equity return recognized $ 13 $ 13 $ 24 $ 24 $ 24 $ 24 $ 45 $ 45

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]	The table below summarizes the Registrants’ outstanding interest rate hedging activity: June 30, 2019 December 31, 2018 Hedging Classification Notional Principal CenterPoint Energy (1) Houston Electric CenterPoint Energy Houston Electric (in millions) Economic hedge $ 84 $ — $ — $ — Cash flow hedge — — 450 450 (1) Relates to interest rate derivative instruments at SIGECO.
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The tables below summarize CenterPoint Energy’s and CERC’s current weather hedge gain (loss) activity: Three Months Ended June 30, 2019 2018 Texas Operations Winter Season Bilateral Cap CenterPoint Energy CERC Winter Season Bilateral Cap CenterPoint Energy CERC (in millions) NGD 2018 – 2019 $ 9 $ — $ — 2017 – 2018 $ 8 $ — $ — Electric operations 2018 – 2019 8 — — 2017 – 2018 9 — — Total (1) $ — $ — $ — $ — Six Months Ended June 30, 2019 2018 Texas Operations Winter Season Bilateral Cap CenterPoint Energy CERC Winter Season Bilateral Cap CenterPoint Energy CERC (in millions) NGD 2018 – 2019 $ 9 $ — $ — 2017 – 2018 $ 8 $ — $ — Electric operations 2018 – 2019 8 3 — 2017 – 2018 9 (4 ) — Total (1) $ 3 $ — $ (4 ) $ — (1) Weather hedge gains (losses) are recorded in Revenues in the Condensed Statements of Consolidated Income.
Fair Value of Derivative Instruments [Table Text Block]	The following tables present information about derivative instruments and hedging activities. The first three tables provide a balance sheet overview of Derivative Assets and Liabilities, while the last two tables provide a breakdown of the related income statement impacts. Fair Value of Derivative Instruments and Hedged Items CenterPoint Energy June 30, 2019 December 31, 2018 Balance Sheet Location Derivative Assets Fair Value Derivative Liabilities Fair Value Derivative Assets Fair Value Derivative Liabilities Fair Value (in millions) Derivatives designated as cash flow hedges: Interest rate derivatives Current Liabilities: Non-trading derivative liabilities $ — $ — $ — $ 24 Derivatives designated as fair value hedges: Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities 11 — 1 7 Derivatives not designated as hedging instruments: Natural gas derivatives (1) (2) (3) Current Assets: Non-trading derivative assets 103 2 103 3 Natural gas derivatives (1) (2) (3) Other Assets: Non-trading derivative assets 44 — 38 — Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities 74 148 62 173 Natural gas derivatives (1) (2) (3) Other Liabilities: Non-trading derivative liabilities 16 41 16 25 Interest rate derivatives Other Liabilities — 8 — — Indexed debt securities derivative Current Liabilities — 755 — 601 Total CenterPoint Energy $ 248 $ 954 $ 220 $ 833 (1) The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 2,186 Bcf or a net 355 Bcf long position and 1,674 Bcf or a net 140 Bcf long position as of June 30, 2019 and December 31, 2018 , respectively. Certain natural gas contracts hedge basis risk only and lack a fixed price exposure. (2) Natural gas contracts are presented on a net basis in CenterPoint Energy’s Condensed Consolidated Balance Sheets as they 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 CenterPoint Energy’s Condensed Consolidated Balance Sheets. The net of total non-trading natural gas derivative assets and liabilities is detailed in the Offsetting of Natural Gas Derivative Assets and Liabilities table below. (3) Derivative Assets and Derivative Liabilities include no material amounts related to physical forward transactions with Enable. Houston Electric June 30, 2019 December 31, 2018 Balance Sheet Location Derivative Assets Fair Value Derivative Liabilities Fair Value Derivative Assets Fair Value Derivative Liabilities Fair Value (in millions) Derivatives designated as cash flow hedges: Interest rate derivatives Current Liabilities: Non-trading derivative liabilities $ — $ — $ — $ 24 Total Houston Electric $ — $ — $ — $ 24 CERC June 30, 2019 December 31, 2018 Balance Sheet Location Derivative Assets Fair Value Derivative Liabilities Fair Value Derivative Assets Fair Value Derivative Liabilities Fair Value (in millions) Derivatives designated as fair value hedges: Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities $ 11 $ — $ 1 $ 7 Derivatives not designated as hedging instruments: Natural gas derivatives (1) (2) (3) Current Assets: Non-trading derivative assets 103 2 103 3 Natural gas derivatives (1) (2) (3) Other Assets: Non-trading derivative assets 44 — 38 — Natural gas derivatives (1) (2) (3) Current Liabilities: Non-trading derivative liabilities 74 142 62 173 Natural gas derivatives (1) (2) (3) Other Liabilities: Non-trading derivative liabilities 16 30 16 25 Total CERC $ 248 $ 174 $ 220 $ 208 (1) The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 2,186 Bcf or a net 355 Bcf long position and 1,674 Bcf or a net 140 Bcf long position as of June 30, 2019 and December 31, 2018 , respectively. Certain natural gas contracts hedge basis risk only and lack a fixed price exposure. (2) Natural gas contracts are presented on a net basis in CERC’s Condensed Consolidated Balance Sheets as they 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 CERC’s Condensed Consolidated Balance Sheets. The net of total non-trading natural gas derivative assets and liabilities is detailed in the Offsetting of Natural Gas Derivative Assets and Liabilities table below. (3) Derivative Assets and Derivative Liabilities include no material amounts related to physical forward transactions with Enable. Cumulative Basis Adjustment for Fair Value Hedges (CenterPoint Energy and CERC) June 30, 2019 Balance Sheet Location Carrying Amount of Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Hedged items in fair value hedge relationship: Natural gas inventory Current Assets: Natural gas inventory $ 48 $ 48 $ (9 ) $ (9 ) Total $ 48 $ 48 $ (9 ) $ (9 ) December 31, 2018 Balance Sheet Location Carrying Amount of Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Hedged items in fair value hedge relationship: Natural gas inventory Current Assets: Natural gas inventory $ 57 $ 57 $ 1 $ 1 Total $ 57 $ 57 $ 1 $ 1
Offsetting of Natural Gas Derivative Assets and Liabilities [Table Text Block]	Offsetting of Natural Gas Derivative Assets and Liabilities (CenterPoint Energy and CERC) CenterPoint Energy June 30, 2019 December 31, 2018 Gross Amounts Recognized (1) Gross Amounts Offset in the Consolidated Balance Sheets Net Amount Presented in the Consolidated Balance Sheets (2) 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 $ 188 $ (87 ) $ 101 $ 166 $ (66 ) $ 100 Other Assets: Non-trading derivative assets 60 (16 ) 44 54 (16 ) 38 Current Liabilities: Non-trading derivative liabilities (149 ) 116 (33 ) (183 ) 81 (102 ) Other Liabilities: Non-trading derivative liabilities (41 ) 23 (18 ) (25 ) 20 (5 ) Total CenterPoint Energy $ 58 $ 36 $ 94 $ 12 $ 19 $ 31 CERC June 30, 2019 December 31, 2018 Gross Amounts Recognized (1) Gross Amounts Offset in the Consolidated Balance Sheets Net Amount Presented in the Consolidated Balance Sheets (2) 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 $ 188 $ (87 ) $ 101 $ 166 $ (66 ) $ 100 Other Assets: Non-trading derivative assets 60 (16 ) 44 54 (16 ) 38 Current Liabilities: Non-trading derivative liabilities (144 ) 116 (28 ) (183 ) 81 (102 ) Other Liabilities: Non-trading derivative liabilities (30 ) 23 (7 ) (25 ) 20 (5 ) Total CERC $ 74 $ 36 $ 110 $ 12 $ 19 $ 31 (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 Registrant’s respective Condensed 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 Text Block]	Income Statement Impact of Hedge Accounting Activity (CenterPoint Energy and CERC) Three Months Ended June 30, 2019 2018 Location and Amount of Gain (Loss) recognized in Income on Hedging Relationship (1) Non-utility cost of revenues, including natural gas CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Total amounts presented in the statements of income in which the effects of hedges are recorded $ 910 $ 769 $ 790 $ 790 Gain (loss) on fair value hedging relationships: Commodity contracts: Hedged items - Natural gas inventory (4 ) (4 ) (12 ) (12 ) Derivatives designated as hedging instruments 4 4 12 12 Amounts excluded from effectiveness testing recognized in earnings immediately (65 ) (65 ) 69 69 Six Months Ended June 30, 2019 2018 Location and Amount of Gain (Loss) recognized in Income on Hedging Relationship (1) Non-utility cost of revenues, including natural gas CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Total amounts presented in the statements of income in which the effects of hedges are recorded $ 2,161 $ 1,940 $ 2,063 $ 2,063 Gain (loss) on fair value hedging relationships: Commodity contracts: Hedged items - Natural gas inventory (10 ) (10 ) (14 ) (14 ) Derivatives designated as hedging instruments 10 10 14 14 Amounts excluded from effectiveness testing recognized in earnings immediately (79 ) (79 ) (2 ) (2 ) (1) Income statement impact associated with cash flow hedge activity is related to gains and losses reclassified from Accumulated other comprehensive income into income. Amounts are immaterial for each Registrant in the three and six months ended June 30, 2019 and 2018, respectively. CenterPoint Energy Three Months Ended June 30, Six Months Ended June 30, Income Statement Location 2019 2018 2019 2018 (in millions) Effects of derivatives not designated as hedging instruments on the income statement: Commodity contracts Gains (losses) in Non-utility revenues $ 86 $ 11 $ 90 $ 68 Indexed debt securities derivative Loss on indexed debt securities (68 ) (254 ) (154 ) (272 ) Total CenterPoint Energy $ 18 $ (243 ) $ (64 ) $ (204 ) CERC Three Months Ended June 30, Six Months Ended June 30, Income Statement Location 2019 2018 2019 2018 (in millions) Effects of derivatives not designated as hedging instruments on the income statement: Commodity contracts Gains (losses) in Non-utility revenues $ 86 $ 11 $ 90 $ 68 Total CERC $ 86 $ 11 $ 90 $ 68
Disclosure of Credit Derivatives [Table Text Block]	CenterPoint Energy and CERC enter into financial derivative contracts containing material adverse change provisions. These provisions could require CenterPoint Energy or CERC to post additional collateral if the S&P or Moody’s credit ratings of CenterPoint Energy, Inc. or its subsidiaries, including CERC Corp., are downgraded. June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Aggregate fair value of derivatives containing material adverse change provisions in a net liability position $ 1 $ 1 $ 1 $ 1 Fair value of collateral already posted — — — — Additional collateral required to be posted if credit risk contingent features triggered 1 1 — —

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair value, assets and liabilities measured on a recurring basis [Table Text Block]	The following tables present information about the Registrants’ assets and liabilities (including derivatives that are presented net) measured at fair value on a recurring basis as of June 30, 2019 and December 31, 2018 and indicate the fair value hierarchy of the valuation techniques utilized by the Registrants to determine such fair value. CenterPoint Energy June 30, 2019 December 31, 2018 Level 1 Level 2 Level 3 Netting (1) Total Level 1 Level 2 Level 3 Netting (1) Total Assets (in millions) Corporate equities $ 690 $ — $ — $ — $ 690 $ 542 $ — $ — $ — $ 542 Investments, including money market funds (2) 63 — — — 63 66 — — — 66 Natural gas derivatives (3)(4) — 215 33 (103 ) 145 — 173 47 (82 ) 138 Hedged portion of natural gas inventory — — — — — 1 — — — 1 Total assets $ 753 $ 215 $ 33 $ (103 ) $ 898 $ 609 $ 173 $ 47 $ (82 ) $ 747 Liabilities Indexed debt securities derivative $ — $ 755 $ — $ — $ 755 $ — $ 601 $ — $ — $ 601 Interest rate derivatives — 8 — — 8 24 — — — 24 Natural gas derivatives (3)(4) — 177 13 (139 ) 51 — 191 17 (101 ) 107 Hedged portion of natural gas inventory 9 — — — 9 — — — — — Total liabilities $ 9 $ 940 $ 13 $ (139 ) $ 823 $ 24 $ 792 $ 17 $ (101 ) $ 732 Houston Electric June 30, 2019 December 31, 2018 Level 1 Level 2 Level 3 Netting Total Level 1 Level 2 Level 3 Netting Total Assets (in millions) Investments, including money market funds (2) $ 47 $ — $ — $ — $ 47 $ 48 $ — $ — $ — $ 48 Total assets $ 47 $ — $ — $ — $ 47 $ 48 $ — $ — $ — $ 48 Liabilities Interest rate derivatives $ — $ — $ — $ — $ — $ 24 $ — $ — $ — $ 24 Total liabilities $ — $ — $ — $ — $ — $ 24 $ — $ — $ — $ 24 CERC June 30, 2019 December 31, 2018 Level 1 Level 2 Level 3 Netting (1) Total Level 1 Level 2 Level 3 Netting (1) Total Assets (in millions) Corporate equities $ 3 $ — $ — $ — $ 3 $ 2 $ — $ — $ — $ 2 Investments, including money market funds (2) 11 — — — 11 11 — — — 11 Natural gas derivatives (3)(4) — 215 33 (103 ) 145 — 173 47 (82 ) 138 Hedged portion of natural gas inventory — — — — — 1 — — — 1 Total assets $ 14 $ 215 $ 33 $ (103 ) $ 159 $ 14 $ 173 $ 47 $ (82 ) $ 152 Liabilities Natural gas derivatives (3)(4) $ — $ 161 $ 13 $ (139 ) $ 35 $ — $ 191 $ 17 $ (101 ) $ 107 Hedged portion of natural gas inventory 9 — — — 9 — — — — — Total liabilities $ 9 $ 161 $ 13 $ (139 ) $ 44 $ — $ 191 $ 17 $ (101 ) $ 107 (1) Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy and CERC to settle positive and negative positions and also include cash collateral posted with the same counterparties as follows: June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Cash collateral posted with the same counterparties $ 36 $ 36 $ 19 $ 19 (2) Amounts are included in Prepaid expenses and other current assets in the Condensed Consolidated Balance Sheets. (3) Natural gas derivatives include no material amounts related to physical forward transactions with Enable. (4) Level 1 natural gas derivatives include exchange-traded derivatives cleared by the CME, which deems that financial instruments cleared by the CME are settled daily in connection with posted cash payments. As a result of this exchange rule, CME-related derivatives are considered to have no fair value at the balance sheet date for financial reporting purposes and are presented in Level 1 net of posted cash; however, the derivatives remain outstanding and subject to future commodity price fluctuations until they are settled in accordance with their contractual terms. Derivative transactions cleared on exchanges other than the CME (e.g., the Intercontinental Exchange or ICE) continue to be reported on a gross basis.
Assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs [Table Text Block]	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 and CERC have utilized Level 3 inputs to determine fair value: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy CERC CenterPoint Energy CERC CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Beginning balance $ 13 $ 13 $ (662 ) $ 12 $ 30 $ 30 $ (622 ) $ 46 Total gains (losses) 13 13 (11 ) 1 12 12 (16 ) 3 Total settlements (2 ) (2 ) 44 (1 ) (17 ) (17 ) 11 (35 ) Transfers into Level 3 (2 ) (2 ) 1 1 (1 ) (1 ) 1 1 Transfers out of Level 3 (2 ) (2 ) — — (4 ) (4 ) (2 ) (2 ) Ending balance (1) $ 20 $ 20 $ (628 ) $ 13 $ 20 $ 20 $ (628 ) $ 13 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: $ 9 $ 9 $ (9 ) $ 3 $ 6 $ 6 $ (23 ) $ (4 ) (1) CenterPoint Energy and CERC did not have significant Level 3 sales or purchases during the three or six months ended June 30, 2019 or 2018 .
Estimated fair value of financial instruments, debt instruments [Table Text Block]	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, CenterPoint Energy’s ZENS indexed debt securities derivative and hedging instruments 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 a combination of historical trading prices and comparable issue data. These liabilities, which are not measured at fair value in the Registrants’ Condensed Consolidated Balance Sheets, but for which the fair value is disclosed, would be classified as Level 2 in the fair value hierarchy. June 30, 2019 December 31, 2018 Carrying Amount Fair Value Carrying Amount Fair Value (in millions) CenterPoint Energy Long-term debt, including current maturities (1) $ 14,587 $ 15,438 $ 9,140 $ 9,308 Houston Electric Long-term debt, including current maturities (1) $ 5,165 $ 5,583 $ 4,717 $ 4,770 CERC Long-term debt, including current maturities $ 2,397 $ 2,641 $ 2,371 $ 2,488 (1) Includes Securitization Bonds debt.

Unconsolidated Affiliate (Cen_2

Unconsolidated Affiliate (CenterPoint Energy and CERC) (Tables)	6 Months Ended
	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments [Table Text Block]	Investment in Unconsolidated Affiliates (CenterPoint Energy): June 30, December 31, 2018 (in millions) Enable $ 2,469 $ 2,482 Other (1) 1 — Total $ 2,470 $ 2,482 (1) Represents the equity investment in ProLiance Holdings, LLC related primarily to an investment in LA Storage, LLC, a joint venture in a development project for salt-cavern natural gas storage, which was acquired in the Merger. This presentation reflects preliminary fair value of the equity investment and is subject to change. See Note 3. Limited Partner Interest and Units Held in Enable (CenterPoint Energy): June 30, 2019 Limited Partner Interest (1) Common Units (2) Enable Series A Preferred Units (3) CenterPoint Energy 53.8 % 233,856,623 14,520,000 OGE 25.5 % 110,982,805 — Public unitholders 20.7 % 90,233,873 — Total units outstanding 100.0 % 435,073,301 14,520,000 (1) Excludes the Enable Series A Preferred Units owned by CenterPoint Energy. (2) Held indirectly through CNP Midstream by CenterPoint Energy. (3) The carrying amount of the Enable Series A Preferred Units, reflected as Preferred units - unconsolidated affiliate on CenterPoint Energy’s Condensed Consolidated Balance Sheets, was $363 million as of June 30, 2019 and $363 million as of December 31, 2018 . No impairment charges or adjustment due to observable price changes were made during the current or prior reporting periods. Interests Held in Enable GP (CenterPoint Energy): June 30, 2019 Management Rights (1) Incentive Distribution Rights (2) CenterPoint Energy (3) 50 % 40 % OGE 50 % 60 % (1) Enable is controlled jointly by CenterPoint Energy and OGE. Sale of CenterPoint Energy’s or OGE’s ownership interests in Enable GP to a third party is subject to mutual rights of first offer and first refusal, and CenterPoint Energy is not permitted to dispose of less than all of its interest in Enable GP. (2) Enable is expected to pay a minimum quarterly distribution of $0.2875 per common unit on its outstanding common units to the extent it has sufficient cash from operations after establishment of cash reserves and payment of fees and expenses, including payments to Enable GP and its affiliates, within 60 days after the end of each quarter. If cash distributions to Enable’s unitholders exceed $0.330625 per common unit in any quarter, Enable GP will receive increasing percentages or incentive distributions rights, up to 50% , of the cash Enable distributes in excess of that amount. In certain circumstances Enable GP will have the right to reset the minimum quarterly distribution and the target distribution levels at which the incentive distributions receive increasing percentages to higher levels based on Enable’s cash distributions at the time of the exercise of this reset election. To date, no incentive distributions have been made. (3) Held indirectly through CNP Midstream. Distributions Received from Enable (CenterPoint Energy and CERC): CenterPoint Energy Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Per Unit Cash Distribution Per Unit Cash Distribution Per Unit Cash Distribution Per Unit Cash Distribution (in millions, except per unit amounts) Enable common units (1) $ 0.3180 $ 75 $ 0.3180 $ 75 $ 0.6360 $ 149 $ 0.6360 $ 149 Enable Series A Preferred Units 0.6250 9 0.6250 9 1.2500 18 1.2500 18 Total CenterPoint Energy $ 84 $ 84 $ 167 $ 167 CERC Three Months Ended June 30, 2018 Six Months Ended June 30, 2018 Per Unit Cash Distribution Per Unit Cash Distribution Enable common units (1) $ 0.3180 $ 75 $ 0.6360 $ 149 Total CERC $ 75 $ 149 (1) Prior to the Internal Spin in September 2018, distributions from Enable were received by CERC. After such date, distributions from Enable were received by CenterPoint Energy. Transactions with Enable (CenterPoint Energy and CERC): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) CenterPoint Energy Natural gas expenses, including transportation and storage costs (1) $ 28 $ 29 $ 63 $ 66 Reimbursement of support services (2) 1 1 3 3 CERC Natural gas expenses, including transportation and storage costs (1) 28 29 63 66 Reimbursement of support services (2) 1 1 3 3 (1) Included in Non-utility costs of revenues, including natural gas on CenterPoint Energy’s and CERC’s respective Condensed Statements of Consolidated Income. (2) Represents amounts billed for certain support services provided to Enable. Actual support services costs are recorded net of reimbursement. June 30, December 31, 2018 (in millions) CenterPoint Energy Accounts payable for natural gas purchases from Enable $ 9 $ 11 Accounts receivable for amounts billed for services provided to Enable 3 2 CERC Accounts payable for natural gas purchases from Enable 9 11 Accounts receivable for amounts billed for services provided to Enable 3 2 CERC’s continuing involvement with Enable subsequent to the Internal Spin described below is limited to its natural gas purchases from Enable. Summarized unaudited consolidated income information for Enable is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Operating revenues $ 735 $ 805 $ 1,530 $ 1,553 Cost of sales, excluding depreciation and amortization 317 444 695 819 Depreciation and amortization 110 96 215 192 Operating income 167 126 332 265 Net income attributable to Enable common units 115 86 228 191 Reconciliation of Equity in Earnings (Losses), net: CenterPoint Energy’s interest $ 62 $ 46 $ 123 $ 103 Basis difference amortization (1) 12 12 24 24 Loss on dilution, net of proportional basis difference recognition — — (11 ) — CenterPoint Energy’s equity in earnings, net $ 74 $ 58 $ 136 $ 127 (1) Equity in earnings of unconsolidated affiliate includes CenterPoint Energy’s share of Enable earnings adjusted for the amortization of the basis difference of CenterPoint Energy’s original investment in Enable and its underlying equity in net assets of Enable. The basis difference is being amortized through the year 2048. Summarized unaudited consolidated balance sheet information for Enable is as follows: June 30, December 31, 2018 (in millions) Current assets $ 376 $ 449 Non-current assets 12,033 11,995 Current liabilities 1,270 1,615 Non-current liabilities 3,580 3,211 Non-controlling interest 37 38 Preferred equity 362 362 Accumulated other comprehensive loss (3 ) — Enable partners’ equity 7,163 7,218 Reconciliation of Investment in Enable: CenterPoint Energy’s ownership interest in Enable partners’ equity $ 3,850 $ 3,896 CenterPoint Energy’s basis difference (1,381 ) (1,414 ) CenterPoint Energy’s equity method investment in Enable $ 2,469 $ 2,482
Discontinued Operations (CERC) [Table Text Block]	On September 4, 2018, CERC completed the Internal Spin. CERC executed the Internal Spin to, among other things, enhance the access of CERC and CenterPoint Energy to low cost debt and equity through increased transparency and understandability of the financial statements, improve CERC’s credit quality by eliminating the exposure to Enable’s midstream business and provide clarity of internal reporting and performance metrics to enhance management’s decision making for CERC and CNP Midstream. The Internal Spin represents a significant strategic shift that has a material effect on CERC’s operations and financial results and, as a result, CERC’s distribution of its equity investment in Enable met the criteria for discontinued operations classification. CERC has no continuing involvement in the equity investment of Enable. Therefore, CERC’s equity in earnings and related income taxes have been classified as Income from discontinued operations, net of tax, in CERC’s Condensed Statements of Consolidated Income for the periods presented. The following table presents amounts included in Income from discontinued operations, net of tax in CERC’s Condensed Statements of Consolidated Income. Three months ended June 30, 2018 Six months ended June 30, 2018 (in millions) Equity in earnings of unconsolidated affiliate, net $ 58 $ 127 Income tax expense 14 31 Income from discontinued operations, net of tax $ 44 $ 96

Goodwill and Other Intangible_2

Goodwill and Other Intangibles (CenterPoint Energy and CERC) (Tables)	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill [Table Text Block]	CenterPoint Energy’s goodwill by reportable segment as of December 31, 2018 and changes in the carrying amount of goodwill as of June 30, 2019 is as follows: December 31, 2018 Additions (1) June 30, (in millions) Indiana Electric Integrated $ — $ 1,008 $ 1,008 Natural Gas Distribution 746 2,529 3,275 Energy Services (2) 110 — 110 Infrastructure Services — 355 355 Corporate and Other 11 420 431 Total $ 867 $ 4,312 $ 5,179 (1) CenterPoint Energy is currently assessing the allocation of goodwill to reportable segments subsequent to the Merger. See Note 3. (2) Amount presented is net of the accumulated goodwill impairment charge of $252 million recorded in 2012. CERC’s goodwill by reportable segment as of June 30, 2019 and December 31, 2018 is as follows: June 30, 2019 December 31, 2018 (in millions) Natural Gas Distribution $ 746 $ 746 Energy Services (1) 110 110 Corporate and Other 11 11 Total $ 867 $ 867 (1) Amount presented is net of the accumulated goodwill impairment charge of $252 million recorded in 2012.
Schedule of Finite-Lived Intangible Assets [Table Text Block]	The tables below present information on CERC’s other intangible assets recorded in Other non-current assets on CERC’s Condensed Consolidated Balance Sheets and the related amortization expense included in Depreciation and amortization on CERC’s Condensed Statements of Consolidated Income. June 30, 2019 December 31, 2018 Gross Carrying Amount Accumulated Amortization Net Balance Gross Carrying Amount Accumulated Amortization Net Balance (in millions) Customer relationships $ 86 $ (30 ) $ 56 $ 86 $ (27 ) $ 59 Covenants not to compete 4 (3 ) 1 4 (3 ) 1 Other 16 (13 ) 3 16 (11 ) 5 Total $ 106 $ (46 ) $ 60 $ 106 $ (41 ) $ 65 The tables below present information on CenterPoint Energy’s other intangible assets recorded in Intangible assets, net on CenterPoint Energy’s Condensed Consolidated Balance Sheets and the related amortization expense included in Depreciation and amortization on CenterPoint Energy’s Condensed Statements of Consolidated Income, unless otherwise indicated. June 30, 2019 December 31, 2018 Gross Carrying Amount Accumulated Amortization Net Balance Gross Carrying Amount Accumulated Amortization Net Balance (in millions) Customer relationships (1) $ 306 $ (36 ) $ 270 $ 86 $ (27 ) $ 59 Covenants not to compete 4 (3 ) 1 4 (3 ) 1 Trade names (1) 62 (3 ) 59 — — — Construction backlog (1) (2) 28 (11 ) 17 — — — Operation and maintenance agreements (1) (2) 12 (1 ) 11 — — — Other (1) 24 (12 ) 12 16 (11 ) 5 Total $ 436 $ (66 ) $ 370 $ 106 $ (41 ) $ 65 (1) The fair value of intangible assets acquired through acquisitions is preliminary and subject to change. See Note 3. (2) Amortization expense related to the operation and maintenance agreements and construction backlog is included in Non-utility cost of revenues, including natural gas on CenterPoint Energy’s Condensed Statements of Consolidated Income.
Finite-lived Intangible Assets Amortization Expense [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Amortization expense of intangible assets recorded in Depreciation and amortization $ 2 $ 2 $ 5 $ 5 Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Amortization expense of intangible assets recorded in Depreciation and amortization (1) $ 7 $ 2 $ 13 $ 5 Amortization expense of intangible assets recorded in Non-utility cost of revenues, including natural gas (2) 3 — 12 — (1) Includes $5 million and $8 million for the three and six months ended June 30, 2019, respectively, of amortization expense related to intangibles acquired in the Merger. The fair value of intangible assets, and related amortization assumptions, acquired through acquisitions during the six months ended June 30, 2019, is preliminary and subject to change. See Note 3. (2) Includes a $4 million benefit related to a cumulative catch-up for remeasurement of the purchase price allocation for the three months ended June 30, 2019 related to the operation and maintenance agreements and construction backlog intangibles acquired in the Merger. The fair value of intangible assets, and related amortization assumptions, acquired through acquisitions during the six months ended June 30, 2019, is preliminary and subject to change. See Note 3.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	CenterPoint Energy and CERC estimate that amortization expense of intangible assets with finite lives for the next five years will be as follows: Amortization Expense CenterPoint Energy CERC (in millions) Remaining six months of 2019 $ 29 $ 6 2020 32 6 2021 31 6 2022 32 6 2023 31 5 2024 29 5

Indexed Debt Securities (ZENS_2

Indexed Debt Securities (ZENS) and Securities Related to ZENS (CenterPoint Energy) (Tables)	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule of Indexed Debt Securities and Marketable Securities [Table Text Block]	A subsidiary of CenterPoint Energy holds shares of certain securities detailed in the table below, which are classified as trading securities and are expected to be held to facilitate CenterPoint Energy’s ability to meet its obligation under the ZENS. Unrealized gains and losses resulting from changes in the market value of the ZENS-Related Securities are recorded in CenterPoint Energy’s Condensed Statements of Consolidated Income. Shares Held June 30, 2019 December 31, 2018 AT&T Common 10,212,945 10,212,945 Charter Common 872,503 872,912 In September 1999, CenterPoint Energy issued ZENS having an original principal amount of $1.0 billion of which $828 million remained outstanding as of June 30, 2019 . Each ZENS is exchangeable at the holder’s option at any time for an amount of cash equal to 95% of the market value of the reference shares attributable to such note. The number and identity of the reference shares attributable to each ZENS are adjusted for certain corporate events. CenterPoint Energy’s reference shares for each ZENS consisted of the following: June 30, 2019 December 31, 2018 (in shares) AT&T Common 0.7185 0.7185 Charter Common 0.061382 0.061382

Short-Term Borrowings and Lon_2

Short-Term Borrowings and Long-term Debt (Tables)	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Schedule of Maturities of Long-term Debt [Table Text Block]	Maturities (CenterPoint Energy). As of June 30, 2019 , maturities of CenterPoint Energy’s long-term debt were as follows: (in millions) Remaining six months of 2019 $ 216 2020 831 2021 2,761 2022 3,769 2023 713 2024 684 2025 and thereafter 5,752
Schedule of Debt [Table Text Block]	(b) Long-term Debt Debt Transactions. During the six months ended June 30, 2019 , the following debt instruments were issued or incurred: Issuance Date Debt Instrument Aggregate Principal Amount Interest Rate as of June 30, 2019 Maturity Date (in millions) Houston Electric January 2019 General mortgage bonds $ 700 4.25 % 2049 CenterPoint Energy (1) February 2019 Variable rate term loan 25 3.14 % 2020 CenterPoint Energy May 2019 Variable rate term loan 1,000 3.17 % 2021 (1) Draw down by VCC on its variable rate term loan. Proceeds from Houston Electric’s debt issuance were used for general limited liability company purposes, including capital expenditures. Proceeds from VCC’s draw down of its term loan were used for general corporate purposes. Proceeds from CenterPoint Energy’s term loan were used for general corporate purposes, including the repayment of commercial paper. Acquired Debt (CenterPoint Energy). The table below summarizes the long-term external debt of Vectren and its subsidiaries that remained outstanding as of June 30, 2019: (in millions) Long-term debt: Senior notes due 2020 to 2045 (1) $ 637 Variable rate term loan due 2020 (2) 300 Variable rate term loan due 2020 (3) 200 First mortgage bonds due 2022 to 2055 (4) 293 Commercial paper (5) 297 Bank revolver (6) 135 Total Vectren debt $ 1,862 (1) Consists of $532 million of senior notes issued by VUHI, $96 million of senior notes issues by Indiana Gas, and $9 million of senior notes issued by VCC. The senior notes have stated interest rates that range from 3.33% to 7.08% . The senior notes issued by VUHI are guaranteed by SIGECO, Indiana Gas and VEDO. The senior notes issued by VCC are guaranteed by Vectren. In connection with the Merger, two of CenterPoint Energy’s acquired wholly-owned subsidiaries, VUHI and VCC, made offers to prepay certain outstanding guaranteed senior notes as required pursuant to certain note purchase agreements previously entered into by VUHI and VCC. In turn, VUHI and VCC borrowed $568 million and $191 million , respectively, from CenterPoint Energy to fund note redemptions effected pursuant to these prepayment offers. To fund these prepayments and payments of approximately $5 million of accrued interest, CenterPoint Energy issued approximately $764 million of commercial paper. (2) Issued by VUHI and guaranteed by SIGECO, Indiana Gas and VEDO. As of June 30, 2019, the term loan was fully drawn upon. The term loan’s interest rate is currently priced at one-month LIBOR, plus a credit spread ranging from 70 to 90 basis points depending on credit rating. (3) Issued by VCC and guaranteed by Vectren. As of June 30, 2019, the term loan was fully drawn upon, exclusive of any potential incremental term loans under the related facility’s accordion feature. The term loan’s interest rate is currently priced at one -month LIBOR, plus a credit spread of 70 basis points. (4) The first mortgage bonds issued by SIGECO subject SIGECO’s properties to a lien under the related mortgage indenture. The first mortgage bonds have stated interest rates that range from 2.375% to 6.72% . (5) Issued by VUHI with maturities up to 30 days. (6) Represents borrowings under the VCC credit facility, which is guaranteed by Vectren.
Schedule of Line of Credit Facilities [Table Text Block]	Credit Facilities . The Registrants had the following revolving credit facilities as of June 30, 2019 : Execution Date Registrant Size of Facility Draw Rate of LIBOR plus (1) Financial Covenant Limit on Debt for Borrowed Money to Capital Ratio Debt for Borrowed Money to Capital Ratio as of June 30, 2019 (2) Termination Date (in millions) March 3, 2016 CenterPoint Energy $ 3,300 1.500% 65% (3) 58.1% March 3, 2022 July 14, 2017 CenterPoint Energy (4) 400 1.125% 65% 52.0% July 14, 2022 July 14, 2017 CenterPoint Energy (5) 200 1.250% 65% 58.0% July 14, 2022 March 3, 2016 Houston Electric 300 1.125% 65% (3) 49.4% March 3, 2022 March 3, 2016 CERC 900 1.250% 65% 46.5% March 3, 2022 Total $ 5,100 (1) Based on current credit ratings. (2) As defined in the revolving credit facility agreements, excluding Securitization Bonds. (3) For CenterPoint Energy and Houston Electric, the financial covenant limit will temporarily increase from 65% to 70% if Houston Electric experiences damage from a natural disaster in its service territory and CenterPoint Energy certifies to the administrative agent that Houston Electric has incurred system restoration costs reasonably likely to exceed $100 million in a consecutive 12 -month period, all or part of which Houston Electric 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. (4) This credit facility was issued by VUHI, is guaranteed by SIGECO, Indiana Gas and VEDO and includes a $10 million swing line sublimit and a $20 million letter of credit sublimit. This credit facility backstops VUHI’s commercial paper program. (5) This credit facility was issued by VCC, is guaranteed by Vectren and includes a $40 million swing line sublimit and an $80 million letter of credit sublimit. The Registrants, including the subsidiaries of CenterPoint Energy discussed above, were in compliance with all financial debt covenants as of June 30, 2019 . The table below reflects the utilization of the Registrants’ respective revolving credit facilities: June 30, 2019 December 31, 2018 Registrant Loans Letters Commercial Weighted Average Interest Rate Loans Letters Commercial Weighted Average Interest Rate (in millions, except weighted average interest rates) CenterPoint Energy (1) $ — $ 6 $ 2,078 2.63 % $ — $ 6 $ — — % CenterPoint Energy (2) — — 297 2.58 % — — — — CenterPoint Energy (3) 135 — — 3.65 % — — — — Houston Electric — 4 — — % — 4 — — CERC — 1 232 2.59 % — 1 210 2.93 % Total $ 135 $ 11 $ 2,607 $ — $ 11 $ 210 (1) CenterPoint Energy’s outstanding commercial paper generally has maturities of 60 days or less. Approximately $1.7 billion was issued to refinance commercial paper used to fund a portion of the cash consideration for the Merger, pay related fees and expenses, pay Vectren’s stub period cash dividend and long-term incentive payments and repay indebtedness of Vectren subsidiaries redeemed at the option of the holder as a result of the closing of the Merger. (2) This credit facility was issued by VUHI and is guaranteed by SIGECO, Indiana Gas and VEDO. (3) This credit facility was issued by VCC and is guaranteed by Vectren. Other. As of June 30, 2019 , certain financial institutions agreed to issue, from time to time, up to $50 million of letters of credit on behalf of Vectren and certain of its subsidiaries in exchange for customary fees. These agreements to issue letters of credit expire on December 31, 2019. As of June 30, 2019 , such financial institutions had issued $21 million of letters of credit on behalf of Vectren and certain of its subsidiaries.

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The Registrants reported the following effective tax rates: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy (1) 13 % 15 % 12 % 27 % Houston Electric (2) 19 % 21 % 19 % 22 % CERC - Continuing operations (3) — % 33 % 14 % 19 % CERC - Discontinued operations (4) n/a 24 % n/a 24 % (1) CenterPoint Energy’s lower effective tax rate for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to the following: an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators in certain jurisdictions; the impact of state tax law changes that resulted in the remeasurement of state deferred taxes; and the release of a valuation allowance on certain state net operating losses that are now expected to be utilized prior to expiration due to a current period law change. (2) Houston Electric’s lower effective tax rate for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators. (3) CERC’s lower effective tax rate on income from continuing operations for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to the following: an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators in certain jurisdictions; the impact of state tax law changes that resulted in the remeasurement of state deferred taxes; and the release of a valuation allowance on certain state net operating losses that are now expected to be utilized prior to expiration due to a current period law change. The state law changes and valuation allowance release resulted in a lower than expected effective tax rate for the three months ended June 30, 2019 as compared to the three months ended June 30, 2018. (4) CERC’s effective tax rate on income from discontinued operations for the three and six months ended June 30, 2018 was a result of the 21% federal income tax rate plus allocable state income taxes. There are no comparable periods in 2019 since the Internal Spin was completed in the third quarter of 2018.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Long-term Purchase Commitment [Table Text Block]	As of June 30, 2019 , minimum purchase obligations are approximately: CenterPoint Energy CERC (in millions) Remaining six months of 2019 $ 399 $ 276 2020 658 459 2021 488 308 2022 576 402 2023 350 197 2024 228 132 2025 and beyond 1,639 1,276
Schedule of Environmental Loss Contingencies by Site [Table Text Block]	Minnesota MGPs (CenterPoint Energy and CERC) . With respect to certain Minnesota MGP sites, CenterPoint Energy and CERC have completed state-ordered remediation and continue state-ordered monitoring and water treatment. CenterPoint Energy and CERC recorded a liability as reflected in the table below for continued monitoring and any future remediation required by regulators in Minnesota. The estimated range of possible remediation costs for the sites for which CenterPoint Energy and CERC believe they may have responsibility was based on remediation continuing for the time frame given in the table below. June 30, 2019 CenterPoint Energy CERC (in millions, except years) Amount accrued for remediation $ 7 $ 7 Minimum estimated remediation costs 4 4 Maximum estimated remediation costs 32 32 Minimum years of remediation 30 30 Maximum years of remediation 50 50

Earnings Per Share (CenterPoi_2

Earnings Per Share (CenterPoint Energy) (Tables)	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table reconciles numerators and denominators of CenterPoint Energy’s basic and diluted earnings per common share. Basic earnings per common share is determined by dividing Income available to common shareholders - basic by the Weighted average common shares outstanding - basic for the applicable period. Diluted earnings per common share is determined by the inclusion of potentially dilutive common stock equivalent shares that may occur if securities to issue Common Stock were exercised or converted into Common Stock. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions, except share and per share amounts) Numerator: Income (loss) available to common shareholders - basic $ 165 $ (75 ) $ 305 $ 90 Add back: Series B Preferred Stock dividend — — — — Income (loss) available to common shareholders - diluted $ 165 $ (75 ) $ 305 $ 90 Denominator: Weighted average common shares outstanding - basic 502,200,000 431,523,000 501,862,000 431,378,000 Plus: Incremental shares from assumed conversions: Restricted stock (1) 2,631,000 — 2,631,000 3,029,000 Series B Preferred Stock (2) — — — — Weighted average common shares outstanding - diluted 504,831,000 431,523,000 504,493,000 434,407,000 Earnings per common share: Basic earnings (loss) per common share $ 0.33 $ (0.17 ) $ 0.61 $ 0.21 Diluted earnings (loss) per common share $ 0.33 $ (0.17 ) $ 0.61 $ 0.21 (1) The potentially dilutive impact from restricted stock awards applies the treasury stock method. Under this method, an increase in the average fair market value of Common Stock can result in a greater dilutive impact from these securities. 3,029,000 incremental shares from assumed conversions of restricted stock have not been included in the computation of diluted earnings (loss) per share for the three months ended June 30, 2018, as their inclusion would be anti-dilutive. (2) The potentially dilutive impact from Series B Preferred Stock applies the if-converted method in calculating diluted earnings per common share. Under this method, diluted earnings per common share is adjusted for the more dilutive effect of the Series B Preferred Stock as a result of either its accumulated dividend for the period in the numerator or the assumed-converted common share equivalent in the denominator. The computation of diluted earnings per common share outstanding for the three and six months ended June 30, 2019 excludes 32,121,000 and 32,121,000 potentially dilutive shares, respectively, because to include them would be anti-dilutive. However, these shares could be potentially dilutive in the future.

Reportable Business Segments (T

Reportable Business Segments (Tables)	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment [Table Text Block]	As of June 30, 2019 , reportable segments by Registrant were as follows: Registrants Houston Electric T&D Indiana Electric Integrated Natural Gas Distribution Energy Services Infrastructure Services Midstream Investments Corporate and Other CenterPoint Energy X X X X X X X Houston Electric X CERC X X X Financial data for reportable segments is as follows: CenterPoint Energy Three Months Ended June 30, 2019 2018 Revenues from Net Operating (Loss) Revenues from Net Operating (in millions) Houston Electric T&D $ 765 (1) $ — $ 169 $ 854 (1) $ — $ 181 Indiana Electric Integrated 140 — 25 — — — Natural Gas Distribution 650 10 47 487 8 7 Energy Services 838 17 29 841 19 15 Infrastructure Services 325 1 24 — — — Midstream Investments (2) — — — — — — Corporate and Other 80 — (7 ) 4 — (16 ) Eliminations — (28 ) — — (27 ) — Consolidated $ 2,798 $ — $ 287 $ 2,186 $ — $ 187 Six Months Ended June 30, 2019 2018 Revenues from External Customers Net Intersegment Revenues Operating Income (Loss) Revenues from External Customers Net Intersegment Revenues Operating (Loss) (in millions) Houston Electric T&D $ 1,454 (1) $ — $ 253 $ 1,605 (1) $ — $ 296 Indiana Electric Integrated 223 — 16 — — — Natural Gas Distribution 2,039 20 214 1,630 18 163 Energy Services 2,020 81 62 2,098 47 (11 ) Infrastructure Services 471 1 8 — — — Midstream Investments (2) — — — — — — Corporate and Other 122 — (21 ) 8 — (10 ) Eliminations — (102 ) — — (65 ) — Consolidated $ 6,329 $ — $ 532 $ 5,341 $ — $ 438 (1) Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113 (2) CenterPoint Energy’s Midstream Investments’ equity earnings, net are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Enable $ 74 $ 58 $ 136 $ 127 Houston Electric Houston Electric consists of a single reportable segment; therefore, a tabular reportable segment presentation has not been included. (1) Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113 CERC Three Months Ended June 30, 2019 2018 Revenues from Net Operating Revenues from Net Operating (in millions) Natural Gas Distribution $ 503 $ 10 $ 28 $ 487 $ 8 $ 7 Energy Services 839 16 29 841 19 15 Other Operations — — 1 — — — Eliminations — (26 ) — — (27 ) — Consolidated $ 1,342 $ — $ 58 $ 1,328 $ — $ 22 Six Months Ended June 30, 2019 2018 Revenues from External Customers Net Intersegment Revenues Operating Income (Loss) Revenues from External Customers Net Intersegment Revenues Operating Income (Loss) (in millions) Natural Gas Distribution $ 1,688 $ 20 $ 192 $ 1,630 $ 18 $ 163 Energy Services 2,021 80 62 2,098 47 (11 ) Corporate and Other 1 — — — — 1 Eliminations — (100 ) — — (65 ) — Consolidated $ 3,710 $ — $ 254 $ 3,728 $ — $ 153 CenterPoint Energy and CERC Total Assets June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint CERC (in millions) Houston Electric T&D $ 11,478 $ — $ 10,509 $ — Indiana Electric Integrated (1) 2,989 — — — Natural Gas Distribution (1) 12,946 6,843 6,956 6,956 Energy Services 1,262 1,262 1,558 1,558 Infrastructure Services (1) 1,303 — — — Midstream Investments 2,915 — 2,482 — Corporate and Other (1) 4,278 (2) 108 6,156 (2) 66 Eliminations (2,982 ) (398 ) (652 ) (366 ) Consolidated $ 34,189 $ 7,815 $ 27,009 $ 8,214 (1) Total assets by reportable segment include assets acquired in the Merger, which are based on preliminary estimates and allocations and are subject to change. See Note 3. (2) Includes pension and other postemployment-related regulatory assets of $639 million and $665 million , respectively, as of June 30, 2019 and December 31, 2018 . Additionally, total assets as of December 31, 2018 included $3.9 billion of temporary investments included in Cash and cash equivalents on CenterPoint Energy’s Consolidated Balance Sheets.
Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]	Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113
Midstream Investments [Table Text Block]	CenterPoint Energy’s Midstream Investments’ equity earnings, net are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Enable $ 74 $ 58 $ 136 $ 127

Supplemental Disclosure of Ca_2

Supplemental Disclosure of Cash Flow Information (Tables)	6 Months Ended
	Jun. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]	The table below provides supplemental disclosure of cash flow information: Six Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Cash Payments/Receipts: Interest, net of capitalized interest $ 231 $ 113 $ 55 $ 167 $ 90 $ 50 Income taxes (refunds), net 142 73 3 88 120 3 Non-cash transactions: Accounts payable related to capital expenditures 173 86 72 133 75 69 ROU assets obtained in exchange for lease liabilities (1) 42 1 28 — — — (1) Includes the transition impact of adoption of ASU 2016-02 Leases. The table below provides a reconciliation of cash, cash equivalents and restricted cash reported in the Condensed Consolidated Balance Sheets to the amount reported in the Condensed Statements of Consolidated Cash Flows: June 30, 2019 December 31, 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Cash and cash equivalents $ 271 $ 260 $ 1 $ 4,231 $ 335 $ 14 Restricted cash included in Prepaid expenses and other current assets 61 33 4 46 34 11 Restricted cash included in Other — — — 1 1 — Total cash, cash equivalents and restricted cash shown in Condensed Statements of Consolidated Cash Flows $ 332 $ 293 $ 5 $ 4,278 $ 370 $ 25

Related Party Transactions (H_2

Related Party Transactions (Houston Electric and CERC) (Tables)	6 Months Ended
	Jun. 30, 2019
Related Party Transactions [Abstract]
Schedule of Money Pool Investment and Borrowing [Table Text Block]	The table below summarizes money pool activity: June 30, 2019 December 31, 2018 Houston Electric CERC Houston Electric CERC (in millions) Money pool investments (borrowings) (1) $ 794 $ 180 $ (1 ) $ 114 Weighted average interest rate 2.67 % 2.67 % 2.42 % 2.42 % (1) Included in Accounts and notes receivable (payable)–affiliated companies on Houston Electric’s and CERC’s respective Condensed Consolidated Balance Sheets.
Schedule of Related Party Transactions [Table Text Block]	Amounts charged for these services were as follows and are included primarily in operation and maintenance expenses: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Houston Electric CERC Houston Electric CERC Houston Electric CERC Houston Electric CERC (in millions) Corporate service charges $ 42 $ 32 $ 47 $ 35 $ 94 $ 75 $ 91 $ 69 Net affiliate service charges (billings) (2 ) 2 (3 ) 3 (4 ) 4 (5 ) 5 Infrastructure Services provides pipeline construction and repair services to CERC. Amounts charged for operation and maintenance expenses by Infrastructure Services to CERC were not significant from February 1, 2019 to June 30, 2019. Additionally, CERC, through CES, sells natural gas to Indiana Electric for use in electric generation activities. Amounts charged by CERC to Indiana Electric were not significant from February 1, 2019 to June 30, 2019. The table below presents transactions among Houston Electric, CERC and their parent, Utility Holding. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Houston Electric CERC Houston Electric CERC Houston Electric CERC Houston Electric CERC (in millions) Cash dividends paid to parent $ 16 $ 83 $ 31 $ 125 $ 40 $ 103 $ 63 $ 211 Cash contribution from parent — — — — 590 — — — Houston Electric and CERC affiliate related net interest income (expense) were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Houston Electric CERC Houston Electric CERC Houston Electric CERC Houston Electric CERC (in millions) Interest income (expense) (1) $ 6 $ 1 $ — $ — $ 9 $ 2 $ — $ (2 ) (1) Interest income is included in Other income (expense), net and interest expense is included in Interest and other finance charges on Houston Electric’s and CERC’s respective Condensed Statements of Consolidated Income.

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Lease, Cost [Table Text Block]	The components of lease cost, included in Operation and maintenance expense on the Registrants’ respective Condensed Statements of Consolidated Income, are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2019 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Operating lease cost $ 7 $ — $ 2 $ 11 $ — $ 3 Short-term lease cost 18 3 — 23 5 — Total lease cost $ 25 $ 3 $ 2 $ 34 $ 5 $ 3
Supplemental Balance Sheet Information Related To Leases [Table Text Block]	Supplemental balance sheet information related to leases was as follows: June 30, 2019 CenterPoint Energy Houston Electric CERC (in millions, except lease term and discount rate) Assets: Operating ROU assets (1) $ 72 $ 1 $ 26 Total leased assets $ 72 $ 1 $ 26 Liabilities: Current operating lease liability (2) $ 22 $ — $ 5 Non-current operating lease liability (3) 50 1 21 Total leased liabilities $ 72 $ 1 $ 26 Weighted-average remaining lease term (in years) - operating leases 5.2 5.5 8.1 Weighted-average discount rate - operating leases 3.41 % 3.51 % 3.67 % (1) Reported within Other assets in the Condensed Consolidated Balance Sheets. (2) Reported within Current other liabilities in the Condensed Consolidated Balance Sheets. (3) Reported within Other liabilities in the Condensed Consolidated Balance Sheets.
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	As of June 30, 2019 , maturities of operating lease liabilities were as follows: CenterPoint Energy Houston Electric CERC (in millions) Remaining six months of 2019 $ 14 $ — $ 3 2020 21 1 5 2021 15 — 4 2022 8 — 4 2023 7 — 3 2024 3 — 2 2025 and beyond 12 — 9 Total lease payments 80 1 30 Less: Interest 8 — 4 Present value of lease liabilities $ 72 $ 1 $ 26
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	The following table sets forth information concerning the Registrants’ obligations under non-cancelable long-term operating leases as of December 31, 2018: CenterPoint Energy Houston Electric CERC (in millions) 2019 $ 6 $ 1 $ 5 2020 6 — 5 2021 5 — 4 2022 4 — 4 2023 3 — 3 2024 and beyond 12 — 11 Total (1) $ 36 $ 1 $ 32 (1) The Merger was completed on February 1, 2019. As such, these amounts are exclusive of Vectren’s leases.
Lessor, Operating Lease, Payments to be Received, Maturity [Table Text Block]	As of June 30, 2019 , maturities of undiscounted operating lease payments to be received are as follows: CenterPoint Energy Houston Electric CERC (in millions) Remaining six months of 2019 $ 2 $ — $ — 2020 2 1 — 2021 2 — — 2022 2 — — 2023 2 — — 2024 2 — — 2025 and beyond 10 — — Total lease payments to be received $ 22 $ 1 $ —
Other Information Related To Leases [Table Text Block]	Other information related to leases is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2019 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Operating cash flows from operating leases included in the measurement of lease liabilities $ 7 $ — $ 1 $ 12 $ 1 $ 2

Equity (Tables)

Equity (Tables)	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Dividends Declared [Table Text Block]	CenterPoint Energy paid dividends on its Common Stock during the six months ended June 30, 2019 and 2018 as presented in the table below: Declaration Date Record Date Payment Date Per Share Total (in millions) December 12, 2018 February 21, 2019 March 14, 2019 $ 0.2875 $ 144 April 25, 2019 May 16, 2019 June 13, 2019 0.2875 144 Total 2019 $ 0.5750 $ 288 December 13, 2017 February 15, 2018 March 8, 2018 $ 0.2775 $ 120 April 26, 2018 May 17, 2018 June 14, 2018 0.2775 120 Total 2018 $ 0.5550 $ 240 CenterPoint Energy declared no dividends on its Series A Preferred Stock or Series B Preferred Stock during the three or six months ended June 30, 2018. CenterPoint Energy paid dividends on its Series A Preferred Stock during the six months ended June 30, 2019 as presented in the table below: Declaration Date Record Date Payment Date Per Share Total (in millions) December 12, 2018 February 15, 2019 March 1, 2019 $ 32.1563 $ 26 Total 2019 $ 32.1563 $ 26 CenterPoint Energy paid dividends on its Series B Preferred Stock during the six months ended June 30, 2019 as presented in the table below: Declaration Date Record Date Payment Date Per Share Total (in millions) December 12, 2018 February 15, 2019 March 1, 2019 $ 17.5000 $ 17 April 25, 2019 May 15, 2019 June 3, 2019 17.5000 17 Total 2019 $ 35.0000 $ 34 Dividend Requirement on Preferred Stock (CenterPoint Energy) Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Series A Preferred Stock $ 13 $ — $ 25 $ — Series B Preferred Stock 17 — 34 — Total preferred stock dividend requirement $ 30 $ — $ 59 $ —
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Changes in accumulated comprehensive income (loss) are as follows: Three Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Beginning Balance $ (107 ) $ (15 ) $ 5 $ (63 ) $ 4 $ 6 Other comprehensive income (loss) before reclassifications: Deferred gain (loss) from interest rate derivatives (1) — — — (1 ) — — Amounts reclassified from accumulated other comprehensive loss: Prior service cost (2) 1 — — 1 — — Actuarial losses (2) 2 — — 1 — — Tax expense (1 ) — — — — — Net current period other comprehensive income 2 — — 1 — — Ending Balance $ (105 ) $ (15 ) $ 5 $ (62 ) $ 4 $ 6 Six Months Ended June 30, 2019 2018 CenterPoint Energy Houston Electric CERC CenterPoint Energy Houston Electric CERC (in millions) Beginning Balance $ (108 ) $ (14 ) $ 5 $ (68 ) $ — $ 6 Other comprehensive income (loss) before reclassifications: Deferred gain (loss) from interest rate derivatives (1) (1 ) (1 ) — 4 5 — Amounts reclassified from accumulated other comprehensive loss: Prior service cost (2) 1 — — 1 — — Actuarial losses (2) 4 — — 3 — — Reclassification of deferred loss from cash flow hedges realized in net income 1 — — — — — Tax expense (2 ) — — (2 ) (1 ) — Net current period other comprehensive income (loss) 3 (1 ) — 6 4 — Ending Balance $ (105 ) $ (15 ) $ 5 $ (62 ) $ 4 $ 6 (1) Gains and losses are reclassified from Accumulated other comprehensive income into income when the hedged transactions affect earnings. The reclassification amounts are included in Interest and other finance charges in each of the Registrants’ respective Statements of Consolidated Income. Over the next twelve months estimated amortization from Accumulated Comprehensive Income into income is expected to be immaterial. (2) Amounts are included in the computation of net periodic cost and are reflected in Other income (expense), net in each of the Registrants’ respective Statements of Consolidated Income.

Subsequent Events (CenterPoin_2

Subsequent Events (CenterPoint Energy) (Tables)	6 Months Ended
	Jun. 30, 2019
Subsequent Events [Abstract]
Schedule of Subsequent Events [Table Text Block]	CenterPoint Energy Dividend Declarations Equity Instrument Declaration Date Record Date Payment Date Per Share Common Stock July 31, 2019 August 15, 2019 September 12, 2019 $ 0.2875 Series A Preferred Stock July 31, 2019 August 15, 2019 September 3, 2019 30.6250 Series B Preferred Stock July 31, 2019 August 15, 2019 September 3, 2019 17.5000 Enable Distributions Declarations (CenterPoint Energy) Equity Instrument Declaration Date Record Date Payment Date Per Unit Distribution Expected Cash Distribution (in millions) Enable common units August 2, 2019 August 20, 2019 August 27, 2019 $ 0.3305 $ 77 Enable Series A Preferred Units August 2, 2019 August 2, 2019 August 14, 2019 0.6250 9

Background and Basis of Prese_3

Background and Basis of Presentation (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019USD ($)stateshares
Enable Midstream Partners [Member]
Ownership percentage of equity method investment	53.80%	[1]
Enable Midstream Partners [Member] | Series A Preferred Units [Member]
Preferred units held | shares	14,520,000	[2]
Natural Gas Distribution [Member]
Number of states in which entity operates	6
Energy Services [Member]
Number of states in which entity operates	30
Enable GP, LLC [Member] | CenterPoint Energy [Member]
Management rights ownership percentage	50.00%	[3],[4]
Incentive distribution right	40.00%	[4],[5]
Vectren [Member]
Amount of cash to be paid to acquire Vectren | $	$ 5,982
[1]	Excludes the Enable Series A Preferred Units owned by CenterPoint Energy.
[2]	The carrying amount of the Enable Series A Preferred Units, reflected as Preferred units - unconsolidated affiliate on CenterPoint Energy’s Condensed Consolidated Balance Sheets, was $363 million as of June 30, 2019 and $363 million as of December 31, 2018 . No impairment charges or adjustment due to observable price changes were made during the current or prior reporting periods.
[3]	Enable is controlled jointly by CenterPoint Energy and OGE. Sale of CenterPoint Energy’s or OGE’s ownership interests in Enable GP to a third party is subject to mutual rights of first offer and first refusal, and CenterPoint Energy is not permitted to dispose of less than all of its interest in Enable GP.
[4]	Held indirectly through CNP Midstream.
[5]	Enable is expected to pay a minimum quarterly distribution of $0.2875 per common unit on its outstanding common units to the extent it has sufficient cash from operations after establishment of cash reserves and payment of fees and expenses, including payments to Enable GP and its affiliates, within 60 days after the end of each quarter. If cash distributions to Enable’s unitholders exceed $0.330625 per common unit in any quarter, Enable GP will receive increasing percentages or incentive distributions rights, up to 50% , of the cash Enable distributes in excess of that amount. In certain circumstances Enable GP will have the right to reset the minimum quarterly distribution and the target distribution levels at which the incentive distributions receive increasing percentages to higher levels based on Enable’s cash distributions at the time of the exercise of this reset election. To date, no incentive distributions have been made.

Mergers and Acquisitions (Cen_3

Mergers and Acquisitions (CenterPoint Energy) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended				6 Months Ended				12 Months Ended
		Jun. 30, 2019		Jun. 30, 2018		Jun. 30, 2019		Jun. 30, 2018		Jun. 30, 2019	Dec. 31, 2018
Dividends declared per share		$ 0.2875		$ 0.2775		$ 0.2875		$ 0.2775
Preliminary purchase price allocation [Abstract]
Goodwill		$ 5,179				$ 5,179				$ 5,179	$ 867
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization of Intangible Assets						12		$ 0
Business Combinations, Additional Disclosures [Abstract]
Revenues		2,798		$ 2,186		6,329		5,341
Net income (Loss)		195		(75)		364		90
Non-utility cost of revenues [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization of Intangible Assets		3	[1]	0		12	[1]	0
Depreciation and amortization expense [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization of Intangible Assets		$ 7	[2]	2		13	[2]	5
Vectren [Member]
Total purchase price consideration						$ 5,982
Cash to be paid per share of Vectren common stock prior to closing of the Merger		$ 72				$ 72				$ 72
Preliminary purchase price allocation [Abstract]
Cash and cash equivalents		$ 16				$ 16				$ 16
Other current assets		598				598				598
Property, plant and equipment, net		5,146				5,146				5,146
Identifiable intangibles		322				322				322
Regulatory assets		338				338				338
Other assets		151				151				151
Total assets acquired		6,571				6,571				6,571
Current liabilities		690				690				690
Regulatory liabilities		944				944				944
Other liabilities		860				860				860
Long-term debt		2,401				2,401				2,401
Total liabilities assumed		4,895				4,895				4,895
Net assets acquired		1,676				1,676				1,676
Goodwill		4,306				4,306				4,306
Total purchase price consideration						5,982
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Estimated Fair Value						322
Business Combinations, Additional Disclosures [Abstract]
Revenues		688				1,161
Net income (Loss)		38				19
Pro Forma Information [Abstract]
Operating revenues		2,798		2,830		6,575		6,644
Net income		199		$ (24)	[3]	371	[4]	83	[5]
Vectren [Member] | Operation and maintenance agreements and construction backlog [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization, Purchase Accounting Adjustments	[1]	4
Vectren [Member] | Depreciation and amortization expense [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization of Intangible Assets	[2]	5				8
Vectren [Member] | Operation and maintenance expense [Member]
Severance expense related to the Merger						61
Business Combinations, Additional Disclosures [Abstract]
Business Combination, Integration Related Costs		40				$ 48
Vectren [Member] | Operation and maintenance agreements [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Weighted Average Useful Lives						24 years
Estimated Fair Value						$ 12
Vectren [Member] | Customer Relationships [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Weighted Average Useful Lives						18 years
Estimated Fair Value						$ 220
Vectren [Member] | Construction Backlog [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Weighted Average Useful Lives						1 year
Estimated Fair Value						$ 28
Vectren [Member] | Trade Names [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Weighted Average Useful Lives						10 years
Estimated Fair Value						$ 62
Vectren [Member] | Operation and maintenance agreements and construction backlog [Member] | Non-utility cost of revenues [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization of Intangible Assets		3				12
Vectren [Member] | Customer relationships and trade names [Member] | Depreciation and amortization expense [Member]
Identifiable intangible assets preliminary purchase price allocation [Abstract]
Amortization of Intangible Assets						$ 8
Vectren [Member] | Stub period [Member]
Dividends declared per share						$ 0.41145
Vectren acquisition [Member]
Cash payments towards outstanding share-based awards		78				$ 78				78
Share-based award liability recorded		41				41				41
Incremental share-based awards expense recorded						37
Utility pipeline construction company [Member]
Total purchase price consideration						21
Preliminary purchase price allocation [Abstract]
Identifiable intangibles		8				8				8
Goodwill		$ 6				6				6
Total purchase price consideration						21
Vectren [Member] | Pro Forma Adjustment [Member] | Vectren acquisition [Member]
Pro Forma Information [Abstract]
Merger-related expenses						$ 37		10		46
CenterPoint Energy [Member] | Pro Forma Adjustment [Member] | Vectren acquisition [Member]
Pro Forma Information [Abstract]
Merger-related expenses								$ 27		$ 1
[1]	Includes a $4 million benefit related to a cumulative catch-up for remeasurement of the purchase price allocation for the three months ended June 30, 2019 related to the operation and maintenance agreements and construction backlog intangibles acquired in the Merger. The fair value of intangible assets, and related amortization assumptions, acquired through acquisitions during the six months ended June 30, 2019, is preliminary and subject to change. See Note 3.
[2]	Includes $5 million and $8 million
[3]	Pro forma net income was adjusted to exclude $10 million and $27 million , respectively, of Vectren and CenterPoint Energy Merger-related transaction costs incurred in 2018 and reflected in the historical income statements.
[4]	Pro forma net income was adjusted to exclude $37 million of Vectren Merger-related transaction costs incurred in 2019.
[5]	Pro forma net income was adjusted to include $46 million and $1 million , respectively, of Vectren and CenterPoint Energy Merger-related transaction costs incurred from July 1, 2018 to June 30, 2019.

Revenue Recognition Disaggregat

Revenue Recognition Disaggregation of Revenue (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue from contracts		$ 2,056	$ 1,449	$ 4,595		$ 3,575
Derivative income (loss)		768	782	1,844		1,885
Other	[1]	2	(18)	(8)		(54)
Revenues		2,798	2,186	6,329		5,341
Houston Electric T&D [Member]
Disaggregation of Revenue [Line Items]
Revenues	[2]	765	854	1,454		1,605
Indiana Electric Integrated [Member]
Disaggregation of Revenue [Line Items]
Revenues		140	0	223		0
Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenues		650	487	2,039		1,630
Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		838	841	2,020		2,098
Infrastructure Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		325	0	471		0
Corporate and Other [Member]
Disaggregation of Revenue [Line Items]
Revenues		80	4	122		8
Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenues		(28)	(27)	(102)		(65)
Intersegment Eliminations [Member] | Houston Electric T&D [Member]
Disaggregation of Revenue [Line Items]
Revenues		0	0	0		0
Intersegment Eliminations [Member] | Indiana Electric Integrated [Member]
Disaggregation of Revenue [Line Items]
Revenues		0	0	0		0
Intersegment Eliminations [Member] | Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenues		(10)	(8)	(20)		(18)
Intersegment Eliminations [Member] | Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		(17)	(19)	(81)		(47)
Intersegment Eliminations [Member] | Infrastructure Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		(1)	0	(1)		0
Intersegment Eliminations [Member] | Corporate and Other [Member]
Disaggregation of Revenue [Line Items]
Revenues		0	0	0		0
Reportable Subsegments [Member] | Houston Electric T&D [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[3]	768	860	1,458		1,621
Derivative income (loss)	[3]	0	0	3		(4)
Other	[1],[3]	(3)	(6)	(7)		(12)
Revenues	[3]	765	854	1,454		1,605
Reportable Subsegments [Member] | Indiana Electric Integrated [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[3]	140	0	223	[4]	0
Derivative income (loss)	[3]	0	0	0	[4]	0
Other	[1],[3]	0	0	0	[4]	0
Revenues	[3]	140	0	223	[4]	0
Reportable Subsegments [Member] | Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[3]	657	509	2,063	[4]	1,695
Derivative income (loss)	[3]	0	0	0	[4]	0
Other	[1],[3]	3	(14)	(4)	[4]	(47)
Revenues	[3]	650	487	2,039	[4]	1,630
Reportable Subsegments [Member] | Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[5]	87	78	260		256
Derivative income (loss)	[5]	768	782	1,841		1,889
Other	[1],[5]	0	0	0		0
Revenues	[5]	838	841	2,020		2,098
Reportable Subsegments [Member] | Infrastructure Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[5]	326	0	472	[4]	0
Derivative income (loss)	[5]	0	0	0	[4]	0
Other	[1],[5]	0	0	0	[4]	0
Revenues	[5]	325	0	471	[4]	0
Reportable Subsegments [Member] | Corporate and Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[5]	78	2	119	[4]	3
Derivative income (loss)	[5]	0	0	0	[4]	0
Other	[1],[5]	2	2	3	[4]	5
Revenues	[5]	80	4	122	[4]	8
Reportable Subsegments [Member] | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[3]		(8)			(18)
Derivative income (loss)	[5]	(17)	(19)	(81)		(47)
Revenues		(28)	(27)	(102)		(65)
Reportable Subsegments [Member] | Intersegment Eliminations [Member] | Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[3]	(10)		(20)	[4]
Reportable Subsegments [Member] | Intersegment Eliminations [Member] | Infrastructure Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[5]	(1)		(1)	[4]
Houston Electric [Member]
Disaggregation of Revenue [Line Items]
Revenues		765	854	1,451		1,609
Houston Electric [Member] | Reportable Subsegments [Member] | Houston Electric T&D [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts		768	860	1,458		1,621
Other	[6]	(3)	(6)	(7)		(12)
Revenues		765	854	1,451		1,609
CERC Corp [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts		597	587	1,969		1,951
Derivative income (loss)		768	782	1,841		1,889
Other	[7]	3	(14)	0		(47)
Revenues		1,342	1,328	3,710		3,728
CERC Corp [Member] | Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenues		503	487	1,688		1,630
CERC Corp [Member] | Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		839	841	2,021		2,098
CERC Corp [Member] | Corporate and Other [Member]
Disaggregation of Revenue [Line Items]
Revenues		0	0	1		0
CERC Corp [Member] | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenues		(26)	(27)	(100)		(65)
CERC Corp [Member] | Intersegment Eliminations [Member] | Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenues		(10)	(8)	(20)		(18)
CERC Corp [Member] | Intersegment Eliminations [Member] | Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		(16)	(19)	(80)		(47)
CERC Corp [Member] | Intersegment Eliminations [Member] | Corporate and Other [Member]
Disaggregation of Revenue [Line Items]
Revenues		0	0	0		0
CERC Corp [Member] | Reportable Subsegments [Member] | Natural Gas Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[8]	510	509	1,708		1,695
Derivative income (loss)	[8]	0	0	0		0
Other	[7],[8]	3	(14)	0		(47)
Revenues	[8]	503	487	1,688		1,630
CERC Corp [Member] | Reportable Subsegments [Member] | Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[9]	87	78	260		256
Derivative income (loss)	[9]	768	782	1,841		1,889
Other	[7],[9]	0	0	0		0
Revenues	[9]	839	841	2,021		2,098
CERC Corp [Member] | Reportable Subsegments [Member] | Corporate and Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[9]	0	0	1		0
Derivative income (loss)	[9]	0	0	0		0
Other	[7],[9]	0	0	0		0
Revenues	[9]	0	0	1		0
CERC Corp [Member] | Reportable Subsegments [Member] | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts	[8]	(10)	(8)	(20)		(18)
Derivative income (loss)	[9]	(16)	(19)	(80)		(47)
Revenues		$ (26)	$ (27)	$ (100)		$ (65)
[1]	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.
[2]	Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113
[3]	Reflected in Utility revenues in the Condensed Statements of Consolidated Income
[4]	Reflects revenues from Vectren subsidiaries for the period from February 1, 2019 to June 30, 2019.
[5]	Reflected in Non-utility revenues in the Condensed Statements of Consolidated Income.
[6]	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.
[7]	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.
[8]	Reflected in Utility revenues in the Condensed Statements of Consolidated Income.
[9]	Reflected in Non-utility revenues in the Condensed Statements of Consolidated Income.

Revenue Recognition Summary of

Revenue Recognition Summary of Contract Assets and Liabilities (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019USD ($)
Change in Accounts Receivable [Roll Forward]
Opening balance as of December 31, 2018 (1)	$ 763	[1]
Closing balance as of June 30, 2019	831
Increase (Decrease) in Accounts Receivable	68
Change in Other Accrued Unbilled Revenues [Roll Forward]
Opening balance as of December 31, 2018 (1)	575	[1]
Closing balance as of June 30, 2019	362
Increase (Decrease) in Other Accrued Unbilled Revenues	(213)
Change in Contract Asset [Roll Forward]
Opening balance as of December 31, 2018 (1)	37	[1]
Closing balance as of June 30, 2019	56
Increase (Decrease) in Contract with Customer, Asset	19
Change in Contract Liability [Roll Forward]
Opening balance as of December 31, 2018 (1)	47	[1]
Closing balance as of June 30, 2019	54
Increase (Decrease) in Contract with Customer, Liability	7
Contract with Customer, Liability, Revenue Recognized	38
Houston Electric [Member]
Change in Accounts Receivable [Roll Forward]
Opening balance as of December 31, 2018 (1)	234
Closing balance as of June 30, 2019	305
Increase (Decrease) in Accounts Receivable	71
Change in Other Accrued Unbilled Revenues [Roll Forward]
Opening balance as of December 31, 2018 (1)	110
Closing balance as of June 30, 2019	122
Increase (Decrease) in Other Accrued Unbilled Revenues	12
Change in Contract Liability [Roll Forward]
Opening balance as of December 31, 2018 (1)	3
Closing balance as of June 30, 2019	5
Increase (Decrease) in Contract with Customer, Liability	2
Contract with Customer, Liability, Revenue Recognized	2
CERC Corp [Member]
Change in Accounts Receivable [Roll Forward]
Opening balance as of December 31, 2018 (1)	282
Closing balance as of June 30, 2019	191
Increase (Decrease) in Accounts Receivable	(91)
Change in Other Accrued Unbilled Revenues [Roll Forward]
Opening balance as of December 31, 2018 (1)	263
Closing balance as of June 30, 2019	87
Increase (Decrease) in Other Accrued Unbilled Revenues	$ (176)
[1]	Opening balances related to Vectren are as of February 1, 2019.

Revenue Recognition Remaining P

Revenue Recognition Remaining Performance Obligations (Details) $ in Millions	Jun. 30, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 317
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	317
Operations and Maintenance and Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	317
Operations and Maintenance and Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	0
Operations and Maintenance and Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 317

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)		$ 24	$ 15	$ 46	$ 30
Total contributions expected in current year		94		94
Total contributions to the plans during the period		27		29
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)		2	2	4	3
Total contributions expected in current year		20		20
Total contributions to the plans during the period		3		8
Operation and maintenance expense [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost (1)	[1]	10	9	20	18
Operation and maintenance expense [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost (1)	[2]	0	1	1	1
Other, net [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost (2)	[3]	25	19	48	39
Expected return on plan assets (2)	[3]	(27)	(26)	(52)	(53)
Amortization of prior service cost (credit) (2)	[3]	2	2	4	4
Amortization of net loss (2)	[3]	13	11	26	22
Settlement cost (3)	[4]	1	0	1	0
Curtailment gain	[5]	0	0	1	0
Other, net [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost (2)	[6]	4	4	8	7
Expected return on plan assets (2)	[6]	(1)	(2)	(3)	(3)
Amortization of prior service cost (credit) (2)	[6]	(1)	(1)	(2)	(2)
Houston Electric [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)		(1)	(1)	(1)	(1)
Total contributions expected in current year		10		10
Total contributions to the plans during the period		2		5
Houston Electric [Member] | Operation and maintenance expense [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost (1)	[2]	0	0	0	0
Houston Electric [Member] | Other, net [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost (2)	[6]	2	2	4	4
Expected return on plan assets (2)	[6]	(1)	(1)	(2)	(2)
Amortization of prior service cost (credit) (2)	[6]	(2)	(2)	(3)	(3)
CERC Corp [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)		1	1	2	2
Total contributions expected in current year		4		4
Total contributions to the plans during the period		1		2
CERC Corp [Member] | Operation and maintenance expense [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost (1)	[2]	1	0	1	0
CERC Corp [Member] | Other, net [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost (2)	[6]	1	1	2	2
Expected return on plan assets (2)	[6]	(1)	(1)	(1)	(1)
Amortization of prior service cost (credit) (2)	[6]	$ 0	$ 1	$ 0	$ 1
[1]	Amounts presented in the table above are included in Operation and maintenance expense in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of amounts capitalized and regulatory deferrals.
[2]	Amounts presented in the tables above are included in Operation and maintenance expense in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of amounts capitalized and regulatory deferrals.
[3]	Amounts presented in the table above are included in Other income (expense), net in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of regulatory deferrals.
[4]	A one-time, non-cash settlement cost is required when the total lump sum distributions or other settlements of plan benefit obligations during a plan year exceed the service cost and interest cost components of the net periodic cost for that year. In June 2019, CenterPoint Energy recognized a non-cash settlement cost of $1 million due to lump sum settlement payments from Vectren pension plans.
[5]	A curtailment gain or loss is required when the expected future services of a significant number of employees are reduced or eliminated for the accrual of benefits. In February 2019, CenterPoint Energy recognized a pension curtailment gain of $1 million related to Vectren employees whose employment was terminated after the Merger closed.
[6]	Amounts presented in the tables above are included in Other income (expense), net in each of the Registrants’ respective Condensed Statements of Consolidated Income, net of regulatory deferrals.

Regulatory Accounting (Details)

Regulatory Accounting (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Securitized regulatory assets		$ 895		$ 895		$ 1,059
Unrecognized equity return (2)	[1]	(189)		(189)		(213)
Unamortized loss on reacquired debt (3)	[2]	65		65		68
Regulatory assets		2,228		2,228		1,967
Total regulatory assets		2,248		2,248		2,044
Regulatory liabilities		3,467		3,467		2,525
Total regulatory liabilities		3,522		3,522		2,563
Total regulatory assets and liabilities, net		(1,274)		(1,274)		(519)
Amount of allowed equity return on the true-up balance that was recognized in the period		13	$ 24	24	$ 45
Houston Electric [Member]
Securitized regulatory assets		895		895		1,059
Unrecognized equity return (2)	[1]	(189)		(189)		(213)
Unamortized loss on reacquired debt (3)	[2]	65		65		68
Regulatory assets		1,016		1,016		1,124
Total regulatory assets		1,016		1,016		1,124
Regulatory liabilities		1,286		1,286		1,298
Total regulatory liabilities		1,291		1,291		1,315
Total regulatory assets and liabilities, net		(275)		(275)		(191)
Amount of allowed equity return on the true-up balance that was recognized in the period		13	$ 24	24	$ 45
CERC Corp [Member]
Securitized regulatory assets		0		0		0
Unrecognized equity return (2)		0		0		0
Unamortized loss on reacquired debt (3)		0		0		0
Regulatory assets		187		187		181
Total regulatory assets		207		207		258
Regulatory liabilities		1,234		1,234		1,227
Total regulatory liabilities		1,277		1,277		1,248
Total regulatory assets and liabilities, net		(1,070)		(1,070)		(990)
Hurricane Harvey [Member]
Regulatory assets	[2]	68		68		68
Hurricane Harvey [Member] | Houston Electric [Member]
Regulatory assets	[2]	64		64		64
Hurricane Harvey [Member] | CERC Corp [Member]
Regulatory assets	[2]	4		4		4
Prepaid expenses and other current assets [Member]
Current regulatory assets (1)	[3]	20		20		77
Prepaid expenses and other current assets [Member] | Houston Electric [Member]
Current regulatory assets (1)	[3]	0		0		0
Prepaid expenses and other current assets [Member] | CERC Corp [Member]
Current regulatory assets (1)	[3]	20		20		77
Other current liabilities [Member]
Current regulatory liabilities (6)	[4]	55		55		38
Other current liabilities [Member] | Houston Electric [Member]
Current regulatory liabilities (6)	[4]	5		5		17
Other current liabilities [Member] | CERC Corp [Member]
Current regulatory liabilities (6)	[4]	43		43		21
Asset Retirement Obligation Costs [Member]
Regulatory assets	[2]	140		140		109
Asset Retirement Obligation Costs [Member] | Houston Electric [Member]
Regulatory assets	[2]	25		25		24
Asset Retirement Obligation Costs [Member] | CERC Corp [Member]
Regulatory assets	[2]	90		90		85
Pension and Other Postretirement Plans Costs [Member]
Regulatory assets	[2]	697		697		725
Pension and Other Postretirement Plans Costs [Member] | Houston Electric [Member]
Regulatory assets	[2]	34		34		33
Pension and Other Postretirement Plans Costs [Member] | CERC Corp [Member]
Regulatory assets	[2]	28		28		30
Amounts related to TCJA [Member]
Regulatory assets	[2],[5]	30		30		33
Amounts related to TCJA [Member] | Houston Electric [Member]
Regulatory assets	[2],[5]	23		23		23
Amounts related to TCJA [Member] | CERC Corp [Member]
Regulatory assets	[2],[5]	7		7		10
Other Regulatory Assets (Liabilities) [Member]
Regulatory assets		389		389		37
Other regulatory assets-not earning a return (5)	[6]	133		133		81
Other Regulatory Assets (Liabilities) [Member] | Houston Electric [Member]
Regulatory assets		25		25		11
Other regulatory assets-not earning a return (5)	[6]	74		74		55
Other Regulatory Assets (Liabilities) [Member] | CERC Corp [Member]
Regulatory assets		30		30		26
Other regulatory assets-not earning a return (5)	[6]	28		28		26
Amounts related to TCJA [Member]
Regulatory liabilities	[5]	1,616		1,616		1,323
Amounts related to TCJA [Member] | Houston Electric [Member]
Regulatory liabilities	[5]	834		834		847
Amounts related to TCJA [Member] | CERC Corp [Member]
Regulatory liabilities	[5]	453		453		476
Removal Costs [Member]
Regulatory liabilities		1,415		1,415		886
Removal Costs [Member] | Houston Electric [Member]
Regulatory liabilities		271		271		269
Removal Costs [Member] | CERC Corp [Member]
Regulatory liabilities		629		629		617
Other Regulatory Assets (Liabilities) [Member]
Regulatory liabilities		436		436		316
Other Regulatory Assets (Liabilities) [Member] | Houston Electric [Member]
Regulatory liabilities		181		181		182
Other Regulatory Assets (Liabilities) [Member] | CERC Corp [Member]
Regulatory liabilities		$ 152		$ 152		$ 134
[1]	The unrecognized equity return will be recognized as it is recovered in rates through 2024. The timing of CenterPoint Energy’s and Houston Electric’s recognition of the equity return will vary each period based on amounts actually collected during the period. The actual amounts recognized are adjusted at least annually to correct any over-collections or under-collections during the preceding 12 months. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric CenterPoint Energy Houston Electric (in millions) Allowed equity return recognized $ 13 $ 13 $ 24 $ 24 $ 24 $ 24 $ 45 $ 45
[2]	Substantially all of these regulatory assets are not earning a return.
[3]	Current regulatory assets are included in Prepaid expenses and other current assets in the Registrants’ respective Condensed Consolidated Balance Sheets.
[4]	Current regulatory liabilities are included in Other current liabilities in each of the Registrants’ respective Condensed Consolidated Balance Sheets.
[5]	The EDIT and deferred revenues will be recovered or refunded to customers as required by tax and regulatory authorities.
[6]	Regulatory assets acquired in the Merger and not earning a return were recorded at fair value as of the Merger Date. Such fair value adjustments are recognized over time until the regulatory asset is recovered.

Derivative Instruments Derivati

Derivative Instruments Derivatives and Hedging (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2019		Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Weather hedges term					10 years
Derivative Assets Fair Value		$ 248			$ 248			$ 220
Derivative Liabilities Fair Value		954			954			833
Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges	[1]	0		$ 0	3		$ (4)
2018 to 2019 [Member] | Natural Gas Distribution [Member]
Derivatives, Fair Value [Line Items]
Weather hedge bilateral cap amount		9			9
2018 to 2019 [Member] | Houston Electric T&D [Member]
Derivatives, Fair Value [Line Items]
Weather hedge bilateral cap amount		8			8
2018 to 2019 [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member] | Natural Gas Distribution [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges		0			0
2018 to 2019 [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member] | Houston Electric T&D [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges		0			3
2017to2018 [Member] | Natural Gas Distribution [Member]
Derivatives, Fair Value [Line Items]
Weather hedge bilateral cap amount				8			8
2017to2018 [Member] | Houston Electric T&D [Member]
Derivatives, Fair Value [Line Items]
Weather hedge bilateral cap amount				9			9
2017to2018 [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member] | Natural Gas Distribution [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges				0			0
2017to2018 [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member] | Houston Electric T&D [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges				0			(4)
Houston Electric [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		0			0			0
Derivative Liabilities Fair Value		0			0			24
CERC Corp [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		248			248			220
Derivative Liabilities Fair Value		174			174			208
CERC Corp [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges	[1]	0		0	0		0
CERC Corp [Member] | 2018 to 2019 [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member] | Natural Gas Distribution [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges		0			0
CERC Corp [Member] | 2017to2018 [Member] | Gains (Losses) in Revenue [Member] | Weather Hedge Swaps [Member] | Natural Gas Distribution [Member]
Derivatives, Fair Value [Line Items]
Recognized gain (loss) on weather hedges				$ 0			$ 0
Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Aggregate notional amount		84	[2]		84	[2]		0
Not Designated as Hedging Instrument, Economic Hedge [Member] | Houston Electric [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Aggregate notional amount		0			0			0
Cash Flow Hedging [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Aggregate notional amount		0			0			450
Cash Flow Hedging [Member] | Houston Electric [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Aggregate notional amount		$ 0			$ 0			$ 450
[1]	Weather hedge gains (losses) are recorded in Revenues in the Condensed Statements of Consolidated Income.
[2]	Relates to interest rate derivative instruments at SIGECO.

Derivative Instruments Summary

Derivative Instruments Summary of Derivative Activity (Details) $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)Bcf	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)Bcf
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		$ 248		$ 248		$ 220
Derivative Liabilities Fair Value		954		954		833
Derivative Asset		48		48		57
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item		(9)		(9)		1
Total amounts presented in the statements of income in which the effects of hedges are recorded	[1]	910	$ 790	2,161	$ 2,063
Gain (loss) on derivative instruments not designated as hedging instruments		18	(243)	(64)	(204)
Aggregate fair value of derivatives containing material adverse change provisions in a net liability position		1		1		1
Fair value of collateral already posted		0		0		0
Additional collateral required to be posted if credit risk contingent features triggered		1		1		0
Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		0		0		0
Derivative Liabilities Fair Value		8		$ 8		$ 0
Energy Related Derivative [Member]
Derivatives, Fair Value [Line Items]
Derivative gross volume notional amount (in Bcf) | Bcf				2,186		1,674
Net amount presented in the consolidated balance sheets	[2]	94		$ 94		$ 31
Gross Amounts Recognized	[3]	58		58		12
Gross Amounts Offset in the Consolidated Balance Sheets		36		36		19
Energy Related Derivative [Member] | Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	[2]	101		101		100
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item		(9)		(9)		1
Gross Amounts Recognized	[3]	188		188		166
Gross Amounts Offset		(87)		(87)		(66)
Energy Related Derivative [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	[2]	44		44		38
Gross Amounts Recognized	[3]	60		60		54
Gross Amounts Offset		(16)		(16)		(16)
Energy Related Derivative [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts Recognized	[3]	(149)		(149)		(183)
Gross Amounts Offset		116		116		81
Derivative Liability	[2]	(33)		(33)		(102)
Energy Related Derivative [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts Recognized	[3]	(41)		(41)		(25)
Gross Amounts Offset		23		23		20
Derivative Liability	[2]	(18)		(18)		(5)
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[4],[5],[6]	103		103		103
Derivative Liabilities Fair Value	[4],[5],[6]	2		2		3
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[4],[5],[6]	44		44		38
Derivative Liabilities Fair Value	[4],[5],[6]	0		0		0
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[4],[5],[6]	74		74		62
Derivative Liabilities Fair Value	[4],[5],[6]	148		148		173
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[4],[5],[6]	16		16		16
Derivative Liabilities Fair Value	[4],[5],[6]	41		$ 41		$ 25
Energy Related Derivative [Member] | Long [Member]
Derivatives, Fair Value [Line Items]
Derivative gross volume notional amount (in Bcf) | Bcf				355		140
IDS Derivative [Member] | Not Designated as Hedging Instrument [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		0		$ 0		$ 0
Derivative Liabilities Fair Value		755		755		601
Houston Electric [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		0		0		0
Derivative Liabilities Fair Value		0		0		24
CERC Corp [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		248		248		220
Derivative Liabilities Fair Value		174		174		208
Derivative Asset		48		48		57
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item		(9)		(9)		1
Total amounts presented in the statements of income in which the effects of hedges are recorded	[1]	769	790	1,940	2,063
Gain (loss) on derivative instruments not designated as hedging instruments		86	11	90	68
Aggregate fair value of derivatives containing material adverse change provisions in a net liability position		1		1		1
Fair value of collateral already posted		0		0		0
Additional collateral required to be posted if credit risk contingent features triggered		1		$ 1		$ 0
CERC Corp [Member] | Energy Related Derivative [Member]
Derivatives, Fair Value [Line Items]
Derivative gross volume notional amount (in Bcf) | Bcf				2,186		1,674
Net amount presented in the consolidated balance sheets	[2]	110		$ 110		$ 31
Gross Amounts Recognized	[3]	74		74		12
Gross Amounts Offset in the Consolidated Balance Sheets		36		36		19
CERC Corp [Member] | Energy Related Derivative [Member] | Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	[2]	101		101		100
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Item		(9)		(9)		1
Gross Amounts Recognized	[3]	188		188		166
Gross Amounts Offset		(87)		(87)		(66)
CERC Corp [Member] | Energy Related Derivative [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	[2]	44		44		38
Gross Amounts Recognized	[3]	60		60		54
Gross Amounts Offset		(16)		(16)		(16)
CERC Corp [Member] | Energy Related Derivative [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts Recognized	[3]	(144)		(144)		(183)
Gross Amounts Offset		116		116		81
Derivative Liability	[2]	(28)		(28)		(102)
CERC Corp [Member] | Energy Related Derivative [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross Amounts Recognized	[3]	(30)		(30)		(25)
Gross Amounts Offset		23		23		20
Derivative Liability	[2]	(7)		(7)		(5)
CERC Corp [Member] | Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[7],[8],[9]	103		103		103
Derivative Liabilities Fair Value	[7],[8],[9]	2		2		3
CERC Corp [Member] | Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[7],[8],[9]	44		44		38
Derivative Liabilities Fair Value	[7],[8],[9]	0		0		0
CERC Corp [Member] | Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[7],[8],[9]	74		74		62
Derivative Liabilities Fair Value	[7],[8],[9]	142		142		173
CERC Corp [Member] | Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[7],[8],[9]	16		16		16
Derivative Liabilities Fair Value	[7],[8],[9]	30		$ 30		$ 25
CERC Corp [Member] | Energy Related Derivative [Member] | Long [Member]
Derivatives, Fair Value [Line Items]
Derivative gross volume notional amount (in Bcf) | Bcf				355		140
Cash Flow Hedging [Member] | Interest Rate Contract [Member] | Designated as Fair Value Hedge [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		0		$ 0		$ 0
Derivative Liabilities Fair Value		0		0		24
Cash Flow Hedging [Member] | Houston Electric [Member] | Interest Rate Contract [Member] | Designated as Fair Value Hedge [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value		0		0		0
Derivative Liabilities Fair Value		0		0		24
Fair Value Hedging [Member] | Energy Related Derivative [Member] | Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		48		48		57
Fair Value Hedging [Member] | Energy Related Derivative [Member] | Designated as Fair Value Hedge [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[4],[5],[6]	11		11		1
Derivative Liabilities Fair Value	[4],[5],[6]	0		0		7
Fair Value Hedging [Member] | CERC Corp [Member] | Energy Related Derivative [Member] | Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		48		48		57
Fair Value Hedging [Member] | CERC Corp [Member] | Energy Related Derivative [Member] | Designated as Fair Value Hedge [Member] | Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets Fair Value	[7],[8],[9]	11		11		1
Derivative Liabilities Fair Value	[7],[8],[9]	0		0		$ 7
Gains (Losses) in Revenue [Member] | Energy Related Derivative [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) on derivative instruments not designated as hedging instruments		86	11	90	68
Gains (Losses) in Revenue [Member] | CERC Corp [Member] | Energy Related Derivative [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) on derivative instruments not designated as hedging instruments		86	11	90	68
Non-utility Natural Gas Expense [Member] | Fair Value Hedging [Member] | Energy Related Derivative [Member]
Derivatives, Fair Value [Line Items]
Change in unrealized gain (loss) on fair value hedging instruments	[1]	(4)	(12)	(10)	(14)
Amounts excluded from effectiveness testing recognized in earnings immediately	[1]	(65)	69	(79)	(2)
Non-utility Natural Gas Expense [Member] | Fair Value Hedging [Member] | Energy Related Derivative [Member] | Designated as Fair Value Hedge [Member]
Derivatives, Fair Value [Line Items]
Change in unrealized gain (loss) on fair value hedging instruments	[1]	4	12	10	14
Non-utility Natural Gas Expense [Member] | Fair Value Hedging [Member] | CERC Corp [Member] | Energy Related Derivative [Member]
Derivatives, Fair Value [Line Items]
Change in unrealized gain (loss) on fair value hedging instruments	[1]	(4)	(12)	(10)	(14)
Amounts excluded from effectiveness testing recognized in earnings immediately	[1]	(65)	69	(79)	(2)
Non-utility Natural Gas Expense [Member] | Fair Value Hedging [Member] | CERC Corp [Member] | Energy Related Derivative [Member] | Designated as Fair Value Hedge [Member]
Derivatives, Fair Value [Line Items]
Change in unrealized gain (loss) on fair value hedging instruments	[1]	4	12	10	14
Gains (Losses) in Other Income (Expense) [Member] | IDS Derivative [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) on derivative instruments not designated as hedging instruments		$ (68)	$ (254)	$ (154)	$ (272)
[1]	Income statement impact associated with cash flow hedge activity is related to gains and losses reclassified from Accumulated other comprehensive income into income. Amounts are immaterial for each Registrant in the three and six months ended June 30, 2019 and 2018, respectively.
[2]	The derivative assets and liabilities on the Registrant’s respective Condensed 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]	Gross amounts recognized include some derivative assets and liabilities that are not subject to master netting arrangements.
[4]	Derivative Assets and Derivative Liabilities include no material amounts related to physical forward transactions with Enable.
[5]	Natural gas contracts are presented on a net basis in CenterPoint Energy’s Condensed Consolidated Balance Sheets as they 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 CenterPoint Energy’s Condensed Consolidated Balance Sheets. The net of total non-trading natural gas derivative assets and liabilities is detailed in the Offsetting of Natural Gas Derivative Assets and Liabilities table below.
[6]	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 2,186 Bcf or a net 355 Bcf long position and 1,674 Bcf or a net 140 Bcf long position as of June 30, 2019 and December 31, 2018 , respectively. Certain natural gas contracts hedge basis risk only and lack a fixed price exposure.
[7]	Derivative Assets and Derivative Liabilities include no material amounts related to physical forward transactions with Enable.
[8]	Natural gas contracts are presented on a net basis in CERC’s Condensed Consolidated Balance Sheets as they 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 CERC’s Condensed Consolidated Balance Sheets. The net of total non-trading natural gas derivative assets and liabilities is detailed in the Offsetting of Natural Gas Derivative Assets and Liabilities table below.
[9]	The fair value shown for natural gas contracts is comprised of derivative gross volumes totaling 2,186 Bcf or a net 355 Bcf long position and 1,674 Bcf or a net 140 Bcf long position as of June 30, 2019 and December 31, 2018 , respectively. Certain natural gas contracts hedge basis risk only and lack a fixed price exposure.

Fair Value Measurements (Detail

Fair Value Measurements (Details) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		$ 823		$ 823		$ 732
Assets
Derivative assets		48		48		57
Assets, Fair Value Disclosure		898		898		747
Total derivative assets, netting adjustment	[1]	(103)		(103)		(82)
Liabilities
Total derivative liabilities, netting adjustment	[1]	(139)		(139)		(101)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		13	$ (662)	30	$ (622)
Total gains (losses)		13	(11)	12	(16)
Total settlements		(2)	44	(17)	11
Transfers into Level 3		(2)	1	(1)	1
Transfers out of Level 3		(2)	0	(4)	(2)
Ending balance (1)	[2]	20	(628)	20	(628)
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:		9	(9)	6	(23)
Carrying Amount [Member]
Estimated Fair Value of Financial Instruments
Long-term debt, including current maturities	[3]	14,587		14,587		9,140
Fair Value [Member]
Estimated Fair Value of Financial Instruments
Long-term debt, including current maturities	[3]	15,438		15,438		9,308
Energy Related Derivative [Member]
Liabilities
Derivative fair value offsets, net		36		36		19
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		9		9		24
Assets
Assets, Fair Value Disclosure		753		753		609
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		940		940		792
Assets
Assets, Fair Value Disclosure		215		215		173
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		13		13		17
Assets
Assets, Fair Value Disclosure		33		$ 33		47
Fair Value, Inputs, Level 3 [Member] | Forward Contracts [Member] | Minimum [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair value inputs (price per MMBtu)				1.62
Fair Value, Inputs, Level 3 [Member] | Forward Contracts [Member] | Maximum [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair value inputs (price per MMBtu)				5.64
Fair Value, Measurements, Recurring [Member]
Assets
Corporate equities		690		$ 690		542
Investments, including money market funds (2)	[4]	63		63		66
Fair Value, Measurements, Recurring [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liabilities		8		8		24
Fair Value, Measurements, Recurring [Member] | Energy Related Derivative [Member]
Assets
Derivative asset, netting adjustment	[1],[5],[6]	(103)		(103)		(82)
Derivative assets	[5],[6]	145		145		138
Liabilities
Derivative liabilities, netting adjustment	[1],[5],[6]	(139)		(139)		(101)
Derivative liabilities	[5],[6]	51		51		107
Fair Value, Measurements, Recurring [Member] | IDS Derivative [Member]
Liabilities
Derivative liabilities, netting adjustment	[1]	0		0		0
Derivative liabilities		755		755		601
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Corporate equities		690		690		542
Investments, including money market funds (2)	[4]	63		63		66
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liability		0		0		24
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Energy Related Derivative [Member]
Assets
Derivative asset	[5],[6]	0		0		0
Liabilities
Derivative liability	[5],[6]	0		0		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | IDS Derivative [Member]
Liabilities
Derivative liability		0		0		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Corporate equities		0		0		0
Investments, including money market funds (2)	[4]	0		0		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liability		8		8		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Energy Related Derivative [Member]
Assets
Derivative asset	[5],[6]	215		215		173
Liabilities
Derivative liability	[5],[6]	177		177		191
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | IDS Derivative [Member]
Liabilities
Derivative liability		755		755		601
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Corporate equities		0		0		0
Investments, including money market funds (2)	[4]	0		0		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liability		0		0		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Energy Related Derivative [Member]
Assets
Derivative asset	[5],[6]	33		33		47
Liabilities
Derivative liability	[5],[6]	13		13		17
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | IDS Derivative [Member]
Liabilities
Derivative liability		0		0		0
Houston Electric [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		0		0		24
Assets
Assets, Fair Value Disclosure		47		47		48
Total derivative assets, netting adjustment		0		0		0
Liabilities
Total derivative liabilities, netting adjustment		0		0		0
Houston Electric [Member] | Carrying Amount [Member]
Estimated Fair Value of Financial Instruments
Long-term debt, including current maturities	[3]	5,165		5,165		4,717
Houston Electric [Member] | Fair Value [Member]
Estimated Fair Value of Financial Instruments
Long-term debt, including current maturities	[3]	5,583		5,583		4,770
Houston Electric [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		0		0		24
Assets
Assets, Fair Value Disclosure		47		47		48
Houston Electric [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		0		0		0
Assets
Assets, Fair Value Disclosure		0		0		0
Houston Electric [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		0		0		0
Assets
Assets, Fair Value Disclosure		0		0		0
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member]
Assets
Investments, including money market funds (2)	[4]	47		47		48
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liabilities		0		0		24
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Investments, including money market funds (2)	[4]	47		47		48
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liability		0		0		24
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Investments, including money market funds (2)	[4]	0		0		0
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liability		0		0		0
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Investments, including money market funds (2)	[4]	0		0		0
Houston Electric [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Contract [Member]
Liabilities
Derivative liability		0		0		0
CERC Corp [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		44		44		107
Assets
Derivative assets		48		48		57
Assets, Fair Value Disclosure		159		159		152
Total derivative assets, netting adjustment	[1]	(103)		(103)		(82)
Liabilities
Total derivative liabilities, netting adjustment	[1]	(139)		(139)		(101)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		13	12	30	46
Total gains (losses)		13	1	12	3
Total settlements		(2)	(1)	(17)	(35)
Transfers into Level 3		(2)	1	(1)	1
Transfers out of Level 3		(2)	0	(4)	(2)
Ending balance (1)	[2]	20	13	20	13
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:		9	$ 3	6	$ (4)
CERC Corp [Member] | Carrying Amount [Member]
Estimated Fair Value of Financial Instruments
Long-term debt, including current maturities		2,397		2,397		2,371
CERC Corp [Member] | Fair Value [Member]
Estimated Fair Value of Financial Instruments
Long-term debt, including current maturities		2,641		2,641		2,488
CERC Corp [Member] | Energy Related Derivative [Member]
Liabilities
Derivative fair value offsets, net		36		36		19
CERC Corp [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		9		9		0
Assets
Assets, Fair Value Disclosure		14		14		14
CERC Corp [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		161		161		191
Assets
Assets, Fair Value Disclosure		215		215		173
CERC Corp [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure		13		13		17
Assets
Assets, Fair Value Disclosure		33		$ 33		47
CERC Corp [Member] | Fair Value, Inputs, Level 3 [Member] | Forward Contracts [Member] | Minimum [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair value inputs (price per MMBtu)				1.62
CERC Corp [Member] | Fair Value, Inputs, Level 3 [Member] | Forward Contracts [Member] | Maximum [Member]
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair value inputs (price per MMBtu)				5.64
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member]
Assets
Corporate equities		3		$ 3		2
Investments, including money market funds (2)	[4]	11		11		11
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Energy Related Derivative [Member]
Assets
Derivative asset, netting adjustment	[1],[5],[6]	(103)		(103)		(82)
Derivative assets	[5],[6]	145		145		138
Liabilities
Derivative liabilities, netting adjustment	[1],[5],[6]	(139)		(139)		(101)
Derivative liabilities	[5],[6]	35		35		107
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Corporate equities		3		3		2
Investments, including money market funds (2)	[4]	11		11		11
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Energy Related Derivative [Member]
Assets
Derivative asset	[5],[6]	0		0		0
Liabilities
Derivative liability	[5],[6]	0		0		0
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Corporate equities		0		0		0
Investments, including money market funds (2)	[4]	0		0		0
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Energy Related Derivative [Member]
Assets
Derivative asset	[5],[6]	215		215		173
Liabilities
Derivative liability	[5],[6]	161		161		191
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Corporate equities		0		0		0
Investments, including money market funds (2)	[4]	0		0		0
CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Energy Related Derivative [Member]
Assets
Derivative asset	[5],[6]	33		33		47
Liabilities
Derivative liability	[5],[6]	13		13		17
Natural gas inventory [Member] | Fair Value, Measurements, Recurring [Member]
Assets
Hedged portion of natural gas inventory		0		0		1
Liabilities
Fair Value Hedge Liabilities		9		9		0
Natural gas inventory [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Hedged portion of natural gas inventory		0		0		1
Liabilities
Fair Value Hedge Liabilities		9		9		0
Natural gas inventory [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Hedged portion of natural gas inventory		0		0		0
Liabilities
Fair Value Hedge Liabilities		0		0		0
Natural gas inventory [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Hedged portion of natural gas inventory		0		0		0
Liabilities
Fair Value Hedge Liabilities		0		0		0
Natural gas inventory [Member] | CERC Corp [Member] | Fair Value, Measurements, Recurring [Member]
Assets
Hedged portion of natural gas inventory		0		0		1
Liabilities
Fair Value Hedge Liabilities		9		9		0
Natural gas inventory [Member] | CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets
Hedged portion of natural gas inventory		0		0		1
Liabilities
Fair Value Hedge Liabilities		9		9		0
Natural gas inventory [Member] | CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets
Hedged portion of natural gas inventory		0		0		0
Liabilities
Fair Value Hedge Liabilities		0		0		0
Natural gas inventory [Member] | CERC Corp [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets
Hedged portion of natural gas inventory		0		0		0
Liabilities
Fair Value Hedge Liabilities		$ 0		$ 0		$ 0
[1]	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy and CERC to settle positive and negative positions and also include cash collateral posted with the same counterparties as follows: June 30, 2019 December 31, 2018 CenterPoint Energy CERC CenterPoint Energy CERC (in millions) Cash collateral posted with the same counterparties $ 36 $ 36 $ 19 $ 19
[2]	CenterPoint Energy and CERC did not have significant Level 3 sales or purchases during the three or six months ended June 30, 2019 or 2018 .
[3]	Includes Securitization Bonds debt.
[4]	Amounts are included in Prepaid expenses and other current assets in the Condensed Consolidated Balance Sheets.
[5]	Level 1 natural gas derivatives include exchange-traded derivatives cleared by the CME, which deems that financial instruments cleared by the CME are settled daily in connection with posted cash payments. As a result of this exchange rule, CME-related derivatives are considered to have no fair value at the balance sheet date for financial reporting purposes and are presented in Level 1 net of posted cash; however, the derivatives remain outstanding and subject to future commodity price fluctuations until they are settled in accordance with their contractual terms. Derivative transactions cleared on exchanges other than the CME (e.g., the Intercontinental Exchange or ICE) continue to be reported on a gross basis.
[6]	Natural gas derivatives include no material amounts related to physical forward transactions with Enable.

Unconsolidated Affiliate (Cen_3

Unconsolidated Affiliate (CenterPoint Energy and CERC) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2019		Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018	Dec. 31, 2018
Enable Units [Abstract]
Preferred units – unconsolidated affiliate		$ 363			$ 363			$ 363
Percentage of sales that trigger right of first refusal					5.00%
Enable Distributions [Abstract]
Total distributions received from Enable		84		$ 84	$ 167		$ 167
Equity Method Investment, Summarized Financial Information, Gross Profit (Loss) [Abstract]
Equity in earnings of unconsolidated affiliate, net		74		58	136		127
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity [Abstract]
Investment in unconsolidated affiliates		2,470			2,470			2,482
CERC Corp [Member]
Enable Distributions [Abstract]
Total distributions received from Enable				75			149
Discontinued Operation, Income (Loss) from Discontinued Operation Disclosures [Abstract]
Income tax expense		0		14	0		31
Income from discontinued operations (net of tax of $-0-, $14, $-0- and $31, respectively)		0		44	$ 0		96
OGE [Member]
Enable Units [Abstract]
Percentage of sales that trigger right of first refusal					5.00%
Proliance Holdings LLC [Member]
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity [Abstract]
Investment in unconsolidated affiliates		$ 1	[1]		$ 1	[1]		0
Enable Midstream Partners [Member]
Enable Partnership Interest [Abstract]
Ownership percentage of equity method investment	[2]	53.80%			53.80%
Equity Method Investment, Summarized Financial Information, Gross Profit (Loss) [Abstract]
Operating revenues		$ 735		805	$ 1,530		1,553
Cost of sales, excluding depreciation and amortization		317		444	695		819
Depreciation and amortization		110		96	215		192
Operating income		167		126	332		265
Net income attributable to Enable common units		115		86	228		191
CenterPoint Energy’s interest		62		46	123		103
Basis difference amortization (1)	[3]	12		12	24		24
Loss on dilution, net of proportional basis difference recognition		0		0	(11)		0
Equity in earnings of unconsolidated affiliate, net		74		58	136		127
Equity Method Investment, Summarized Financial Information, Assets and Liabilities [Abstract]
Current assets		376			376			449
Non-current assets		12,033			12,033			11,995
Current liabilities		1,270			1,270			1,615
Non-current liabilities		3,580			3,580			3,211
Non-controlling interest		37			37			38
Preferred equity		362			362			362
Accumulated other comprehensive loss		(3)			(3)			0
Enable partners’ equity		7,163			7,163			7,218
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity [Abstract]
CenterPoint Energy’s ownership interest in Enable partners’ equity		3,850			3,850			3,896
CenterPoint Energy’s basis difference		(1,381)			(1,381)			(1,414)
Investment in unconsolidated affiliates		2,469			2,469			2,482
Enable Midstream Partners [Member] | Common Units [Member]
Enable Distributions [Abstract]
Distributions received from Enable equity method investment	[4]	$ 75		$ 75	$ 149		$ 149
Distribution per share of common units		$ 0.3180		$ 0.3180	$ 0.6360		$ 0.6360
Enable Midstream Partners [Member] | Series A Preferred Units [Member]
Enable Distributions [Abstract]
Distributions received from Enable cost method investment		$ 9		$ 9	$ 18		$ 18
Distribution per share of Series A preferred units		$ 0.6250		$ 0.6250	$ 1.2500		$ 1.2500
Enable Midstream Partners [Member] | CERC Corp [Member] | Common Units [Member]
Enable Distributions [Abstract]
Distributions received from Enable equity method investment	[4]			$ 75			$ 149
Distribution per share of common units				$ 0.3180			$ 0.6360
Common Units [Member] | Enable Midstream Partners [Member]
Enable Units [Abstract]
Limited partner interest units held	[5]	233,856,623			233,856,623
Series A Preferred Units [Member] | Enable Midstream Partners [Member]
Enable Units [Abstract]
Preferred Units Held	[6]	14,520,000			14,520,000
Transitional Service [Member] | Enable Midstream Partners [Member]
Transactions with Enable [Abstract]
Reimbursement of support services (2)	[7]	$ 1		$ 1	$ 3		$ 3
Accounts receivable for amounts billed for services provided to Enable		3			3			2
Transitional Service [Member] | Enable Midstream Partners [Member] | CERC Corp [Member]
Transactions with Enable [Abstract]
Reimbursement of support services (2)	[7]	1		1	3		3
Accounts receivable for amounts billed for services provided to Enable		3			3			2
Natural Gas Expenses [Member] | Enable Midstream Partners [Member]
Transactions with Enable [Abstract]
Natural gas expenses, including transportation and storage costs (1)	[8]	28		29	63		66
Accounts payable for natural gas purchases from Enable		9			9			11
Natural Gas Expenses [Member] | Enable Midstream Partners [Member] | CERC Corp [Member]
Transactions with Enable [Abstract]
Natural gas expenses, including transportation and storage costs (1)	[8]	28		29	63		66
Accounts payable for natural gas purchases from Enable		$ 9			$ 9			$ 11
Enable Midstream Partners [Member]
Enable Partnership Interest [Abstract]
Limited partner ownership interest	[2]				100.00%
Enable Units [Abstract]
Maximum incentive distribution right					50.00%
Enable Midstream Partners [Member] | OGE [Member]
Enable Partnership Interest [Abstract]
Limited partner ownership interest	[2]				25.50%
Enable Midstream Partners [Member] | Public unitholders [Member]
Enable Partnership Interest [Abstract]
Limited partner ownership interest	[2]				20.70%
Enable Midstream Partners [Member] | Minimum [Member]
Enable Units [Abstract]
Incentive distribution per unit					$ 0.2875
Enable Midstream Partners [Member] | Maximum [Member]
Enable Units [Abstract]
Incentive distribution per unit					$ 0.330625
Enable Midstream Partners [Member] | Common Units [Member]
Enable Units [Abstract]
Limited partner interest units held	[5]	435,073,301			435,073,301
Enable Midstream Partners [Member] | Common Units [Member] | OGE [Member]
Enable Units [Abstract]
Limited partner interest units held	[5]	110,982,805			110,982,805
Enable Midstream Partners [Member] | Common Units [Member] | Public unitholders [Member]
Enable Units [Abstract]
Limited partner interest units held	[5]	90,233,873			90,233,873
Enable GP, LLC [Member] | CenterPoint Energy [Member]
Enable Units [Abstract]
Management rights ownership percentage	[9],[10]				50.00%
Incentive distribution right	[10],[11]				40.00%
Enable GP, LLC [Member] | OGE [Member]
Enable Units [Abstract]
Management rights ownership percentage	[9]				50.00%
Incentive distribution right	[11]				60.00%
Enable Midstream Partners [Member] | Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member] | CERC Corp [Member]
Discontinued Operation, Income (Loss) from Discontinued Operation Disclosures [Abstract]
Equity in earnings of unconsolidated affiliate, net				58			127
Income tax expense				14			31
Income from discontinued operations (net of tax of $-0-, $14, $-0- and $31, respectively)				$ 44			$ 96
[1]	Represents the equity investment in ProLiance Holdings, LLC related primarily to an investment in LA Storage, LLC, a joint venture in a development project for salt-cavern natural gas storage, which was acquired in the Merger. This presentation reflects preliminary fair value of the equity investment and is subject to change. See Note 3.
[2]	Excludes the Enable Series A Preferred Units owned by CenterPoint Energy.
[3]	Equity in earnings of unconsolidated affiliate includes CenterPoint Energy’s share of Enable earnings adjusted for the amortization of the basis difference of CenterPoint Energy’s original investment in Enable and its underlying equity in net assets of Enable. The basis difference is being amortized through the year 2048.
[4]	Prior to the Internal Spin in September 2018, distributions from Enable were received by CERC. After such date, distributions from Enable were received by CenterPoint Energy.
[5]	Held indirectly through CNP Midstream by CenterPoint Energy.
[6]	The carrying amount of the Enable Series A Preferred Units, reflected as Preferred units - unconsolidated affiliate on CenterPoint Energy’s Condensed Consolidated Balance Sheets, was $363 million as of June 30, 2019 and $363 million as of December 31, 2018 . No impairment charges or adjustment due to observable price changes were made during the current or prior reporting periods.
[7]	Represents amounts billed for certain support services provided to Enable. Actual support services costs are recorded net of reimbursement.
[8]	Included in Non-utility costs of revenues, including natural gas on CenterPoint Energy’s and CERC’s respective Condensed Statements of Consolidated Income.
[9]	Enable is controlled jointly by CenterPoint Energy and OGE. Sale of CenterPoint Energy’s or OGE’s ownership interests in Enable GP to a third party is subject to mutual rights of first offer and first refusal, and CenterPoint Energy is not permitted to dispose of less than all of its interest in Enable GP.
[10]	Held indirectly through CNP Midstream.
[11]	Enable is expected to pay a minimum quarterly distribution of $0.2875 per common unit on its outstanding common units to the extent it has sufficient cash from operations after establishment of cash reserves and payment of fees and expenses, including payments to Enable GP and its affiliates, within 60 days after the end of each quarter. If cash distributions to Enable’s unitholders exceed $0.330625 per common unit in any quarter, Enable GP will receive increasing percentages or incentive distributions rights, up to 50% , of the cash Enable distributes in excess of that amount. In certain circumstances Enable GP will have the right to reset the minimum quarterly distribution and the target distribution levels at which the incentive distributions receive increasing percentages to higher levels based on Enable’s cash distributions at the time of the exercise of this reset election. To date, no incentive distributions have been made.

Goodwill and Other Intangible_3

Goodwill and Other Intangibles (CenterPoint Energy and CERC) (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2019		Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018	Dec. 31, 2018
Goodwill [Line Items]
Goodwill		$ 5,179			$ 5,179			$ 867
Goodwill, Acquired During Period	[1]				4,312
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		436			436			106
Intangible assets accumulated amortization		(66)			(66)			(41)
Net intangible assets		370			370			65
Amortization of Intangible Assets					12		$ 0
Finite-Lived Intangible Assets Amortization Expense Maturity Schedule [Abstract]
Remaining six months of 2019		29			29
2020		32			32
2021		31			31
2022		32			32
2023		31			31
2024		29			29
Indiana Electric Integrated [Member]
Goodwill [Line Items]
Goodwill		1,008			1,008			0
Goodwill, Acquired During Period	[1]				1,008
Natural Gas Distribution [Member]
Goodwill [Line Items]
Goodwill		3,275			3,275			746
Goodwill, Acquired During Period	[1]				2,529
Energy Services [Member]
Goodwill [Line Items]
Goodwill	[2]	110			110			110
Accumulated goodwill impairment charge recorded in 2012		252			252			252
Infrastructure Services [Member]
Goodwill [Line Items]
Goodwill		355			355			0
Goodwill, Acquired During Period	[1]				355
Corporate and Other [Member]
Goodwill [Line Items]
Goodwill		431			431			11
Goodwill, Acquired During Period	[1]				420
Customer Relationships [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		306	[3]		306	[3]		86
Intangible assets accumulated amortization		(36)	[3]		(36)	[3]		(27)
Net intangible assets		270	[3]		270	[3]		59
Noncompete Agreements [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		4			4			4
Intangible assets accumulated amortization		(3)			(3)			(3)
Net intangible assets		1			1			1
Trade Names [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		62	[3]		62	[3]		0
Intangible assets accumulated amortization		(3)	[3]		(3)	[3]		0
Net intangible assets		59	[3]		59	[3]		0
Construction Backlog [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		28	[3],[4]		28	[3],[4]		0
Intangible assets accumulated amortization		(11)	[3],[4]		(11)	[3],[4]		0
Net intangible assets		17	[3],[4]		17	[3],[4]		0
Operation and maintenance agreements [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		12	[3],[4]		12	[3],[4]		0
Intangible assets accumulated amortization		(1)	[3],[4]		(1)	[3],[4]		0
Net intangible assets		11	[3],[4]		11	[3],[4]		0
Other [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount	[3]	24			24			16
Intangible assets accumulated amortization	[3]	(12)			(12)			(11)
Net intangible assets	[3]	12			12			5
CERC Corp [Member]
Goodwill [Line Items]
Goodwill		867			867			867
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		106			106			106
Intangible assets accumulated amortization		(46)			(46)			(41)
Net intangible assets		60			60			65
Finite-Lived Intangible Assets Amortization Expense Maturity Schedule [Abstract]
Remaining six months of 2019		6			6
2020		6			6
2021		6			6
2022		6			6
2023		5			5
2024		5			5
CERC Corp [Member] | Natural Gas Distribution [Member]
Goodwill [Line Items]
Goodwill		746			746			746
CERC Corp [Member] | Energy Services [Member]
Goodwill [Line Items]
Goodwill	[5]	110			110			110
Accumulated goodwill impairment charge recorded in 2012		252			252			252
CERC Corp [Member] | Corporate and Other [Member]
Goodwill [Line Items]
Goodwill		11			11			11
CERC Corp [Member] | Customer Relationships [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		86			86			86
Intangible assets accumulated amortization		(30)			(30)			(27)
Net intangible assets		56			56			59
CERC Corp [Member] | Noncompete Agreements [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		4			4			4
Intangible assets accumulated amortization		(3)			(3)			(3)
Net intangible assets		1			1			1
CERC Corp [Member] | Other [Member]
Finite-Live Intangible Assets [Abstract]
Intangible assets gross carrying amount		16			16			16
Intangible assets accumulated amortization		(13)			(13)			(11)
Net intangible assets		3			3			$ 5
Depreciation and amortization expense [Member]
Finite-Live Intangible Assets [Abstract]
Amortization of Intangible Assets		7	[6]	$ 2	13	[6]	5
Depreciation and amortization expense [Member] | CERC Corp [Member]
Finite-Live Intangible Assets [Abstract]
Amortization of Intangible Assets		2		2	5		5
Operation and maintenance agreements and construction backlog [Member]
Finite-Live Intangible Assets [Abstract]
Amortization of Intangible Assets		3	[7]	$ 0	12	[7]	$ 0
Vectren [Member]
Goodwill [Line Items]
Goodwill		4,306			4,306
Vectren [Member] | Depreciation and amortization expense [Member]
Finite-Live Intangible Assets [Abstract]
Amortization of Intangible Assets	[6]	5			$ 8
Vectren [Member] | Operation and maintenance agreements and construction backlog [Member]
Finite-Live Intangible Assets [Abstract]
Amortization, Purchase Accounting Adjustments	[7]	$ 4
[1]	CenterPoint Energy is currently assessing the allocation of goodwill to reportable segments subsequent to the Merger. See Note 3.
[2]	Amount presented is net of the accumulated goodwill impairment charge of $252 million recorded in 2012.
[3]	The fair value of intangible assets acquired through acquisitions is preliminary and subject to change. See Note 3.
[4]	Amortization expense related to the operation and maintenance agreements and construction backlog is included in Non-utility cost of revenues, including natural gas on CenterPoint Energy’s Condensed Statements of Consolidated Income.
[5]	Amount presented is net of the accumulated goodwill impairment charge of $252 million recorded in 2012.
[6]	Includes $5 million and $8 million
[7]	Includes a $4 million benefit related to a cumulative catch-up for remeasurement of the purchase price allocation for the three months ended June 30, 2019 related to the operation and maintenance agreements and construction backlog intangibles acquired in the Merger. The fair value of intangible assets, and related amortization assumptions, acquired through acquisitions during the six months ended June 30, 2019, is preliminary and subject to change. See Note 3.

Indexed Debt Securities (ZENS_3

Indexed Debt Securities (ZENS) and Securities Related to ZENS (CenterPoint Energy) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
TargetAnnualYieldOnReferenceShares	2.309%
Subordinated Debt ZENS [Member]
Principal amount of debt issued	$ 1,000
Outstanding debt balance	$ 828
Subordinated note cash exchangeable percentage of fair value	95.00%
Debt Instrument, Interest Rate, Stated Percentage	2.00%
Contingent principal amount outstanding	$ 84
AT&T Common [Member]
Balance of investment owned (in shares)	10,212,945	10,212,945
AT&T Common [Member] | Subordinated Debt ZENS [Member]
Number of shares referenced in exchangeable subordinated note	0.7185	0.7185
Charter Common [Member]
Balance of investment owned (in shares)	872,503	872,912
Charter Common [Member] | Subordinated Debt ZENS [Member]
Number of shares referenced in exchangeable subordinated note	0.061382	0.061382

Short-Term Borrowings and Lon_3

Short-Term Borrowings and Long-term Debt (Details) $ in Millions		6 Months Ended
		Jun. 30, 2019USD ($)day	May 15, 2019USD ($)	Feb. 08, 2019USD ($)	[14]	Jan. 15, 2019USD ($)	Dec. 31, 2018USD ($)
Acquired Long-term Debt [Abstract]
Accrued interest expense		$ 5
Commercial paper issued in connection with the Merger		$ 764
Number of days until commercial paper maturity | day		60
Line of Credit Facility [Abstract]
Size of credit facility		$ 5,100
Number of days until commercial paper maturity | day		60
VCC [Member]
Line of Credit Facility [Abstract]
Size of credit facility	[1]	$ 200
Credit facility swing line sublimit		40
Letters of credit swing line sublimit		80
Parent Company [Member]
Line of Credit Facility [Abstract]
Size of credit facility		3,300
VUHI [Member]
Line of Credit Facility [Abstract]
Size of credit facility	[2]	400
Credit facility swing line sublimit		10
Letters of credit swing line sublimit		20
Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt		1,862
Houston Electric [Member]
Debt Instruments [Abstract]
General mortgage bonds used as collateral		68					$ 68
Line of Credit Facility [Abstract]
Size of credit facility		300
VUHI [Member]
Acquired Long-term Debt [Abstract]
Intercompany notes payable established as a result of the merger		$ 568
Number of days until commercial paper maturity | day		30
Line of Credit Facility [Abstract]
Number of days until commercial paper maturity | day		30
VCC [Member]
Acquired Long-term Debt [Abstract]
Intercompany notes payable established as a result of the merger		$ 191
Basis spread on LIBOR		70.00%
Line of Credit Facility [Abstract]
Basis spread on LIBOR		70.00%
CERC Corp [Member]
Line of Credit Facility [Abstract]
Size of credit facility		$ 900
Revolving Credit Facility [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		135					0
Revolving Credit Facility [Member] | VCC [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[3]	135
Revolving Credit Facility [Member] | Parent Company [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[4]	0					0
Revolving Credit Facility [Member] | VUHI [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[5]	0
Revolving Credit Facility [Member] | Houston Electric [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		0					0
Revolving Credit Facility [Member] | CERC Corp [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		$ 0					0
Line of Credit [Member] | VCC [Member]
Line of Credit Facility [Abstract]
Percentage on limitation of debt to total capitalization under covenant	[1]	65.00%
Ratio of indebtedness to net capital	[1],[6]	0.580
Line of Credit [Member] | VCC [Member] | London Interbank Offered Rate (LIBOR) [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR	[1],[7]	1.25%
Line of Credit Facility [Abstract]
Basis spread on LIBOR	[1],[7]	1.25%
Line of Credit [Member] | Parent Company [Member]
Line of Credit Facility [Abstract]
Percentage on limitation of debt to total capitalization under covenant	[8]	65.00%
Percentage on limitation of debt to total capitalization under covenant amended (in hundredths)		70.00%
Ratio of indebtedness to net capital	[6]	0.581
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
Line of Credit [Member] | Parent Company [Member] | London Interbank Offered Rate (LIBOR) [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR	[7]	1.50%
Line of Credit Facility [Abstract]
Basis spread on LIBOR	[7]	1.50%
Line of Credit [Member] | VUHI [Member]
Line of Credit Facility [Abstract]
Percentage on limitation of debt to total capitalization under covenant	[2]	65.00%
Ratio of indebtedness to net capital	[2],[6]	0.520
Line of Credit [Member] | VUHI [Member] | London Interbank Offered Rate (LIBOR) [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR	[2],[7]	1.125%
Line of Credit Facility [Abstract]
Basis spread on LIBOR	[2],[7]	1.125%
Line of Credit [Member] | Houston Electric [Member]
Line of Credit Facility [Abstract]
Percentage on limitation of debt to total capitalization under covenant	[8]	65.00%
Ratio of indebtedness to net capital	[6]	0.494
Line of Credit [Member] | Houston Electric [Member] | London Interbank Offered Rate (LIBOR) [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR	[7]	1.125%
Line of Credit Facility [Abstract]
Basis spread on LIBOR	[7]	1.125%
Line of Credit [Member] | CERC Corp [Member]
Line of Credit Facility [Abstract]
Percentage on limitation of debt to total capitalization under covenant		65.00%
Ratio of indebtedness to net capital	[6]	0.465
Line of Credit [Member] | CERC Corp [Member] | London Interbank Offered Rate (LIBOR) [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR	[7]	1.25%
Line of Credit Facility [Abstract]
Basis spread on LIBOR	[7]	1.25%
Letter of Credit [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		$ 11					11
Letter of Credit [Member] | VCC [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[3]	0
Letter of Credit [Member] | Parent Company [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[4]	6					6
Letter of Credit [Member] | VUHI [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[5]	0
Letter of Credit [Member] | SIGECO [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		21
Letter of Credit [Member] | Houston Electric [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		4					4
Letter of Credit [Member] | CERC Corp [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		1					1
Commercial Paper [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		2,607					210
Commercial Paper [Member] | VCC [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[3]	$ 0
Weighted average interest rate of debt	[3]	3.65%
Commercial Paper [Member] | Parent Company [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[4]	$ 2,078					$ 0
Weighted average interest rate of debt	[4]	2.63%					0.00%
Commercial Paper [Member] | VUHI [Member]
Line of Credit Facility [Abstract]
Long-term line of credit	[5]	$ 297
Weighted average interest rate of debt	[5]	2.58%
Commercial Paper [Member] | Houston Electric [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		$ 0					$ 0
Commercial Paper [Member] | CERC Corp [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		$ 232					$ 210
Weighted average interest rate of debt		2.59%					2.93%
Long term Debt Excluding ZENS [Member]
Maturities of Long-term Debt [Abstract]
Remaining six months of 2019		$ 216
2020		831
2021		2,761
2022		3,769
2023		713
2024		684
2025 and thereafter		$ 5,752
General Mortgage Bonds Due 2049 [Member] | Houston Electric [Member]
Debt Instruments [Abstract]
Principal amount of debt issued						$ 700
Interest rate of debt		4.25%
Acquired Long-term Debt [Abstract]
Interest rate of debt		4.25%
Revolving Credit Facility [Member] | Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt	[9]	$ 135
Variable term rate loan 2 [Member]
Debt Instruments [Abstract]
Interest rate of debt		3.17%
Acquired Long-term Debt [Abstract]
Interest rate of debt		3.17%
Variable term rate loan 2 [Member] | Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt	[10]	$ 200
First Mortgage Bonds [Member] | Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt	[11]	293
Commercial Paper [Member] | Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt	[12]	297
Senior Notes Due Range 2 [Member] | Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt	[13]	637
Senior Notes Due Range 2 [Member] | VUHI [Member]
Acquired Long-term Debt [Abstract]
Long-term debt		532
Senior Notes Due Range 2 [Member] | Indiana Gas [Member]
Acquired Long-term Debt [Abstract]
Long-term debt		96
Senior Notes Due Range 2 [Member] | VCC [Member]
Acquired Long-term Debt [Abstract]
Long-term debt		$ 9
Variable rate term loan [Member]
Debt Instruments [Abstract]
Principal amount of debt issued			$ 1,000	$ 25
Interest rate of debt	[14]	3.14%
Acquired Long-term Debt [Abstract]
Interest rate of debt	[14]	3.14%
Variable rate term loan [Member] | Vectren [Member]
Acquired Long-term Debt [Abstract]
Long-term debt	[15]	$ 300
Vectren acquisition [Member] | Commercial Paper [Member] | Parent Company [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		$ 1,700
Minimum [Member] | VUHI [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR		70.00%
Line of Credit Facility [Abstract]
Basis spread on LIBOR		70.00%
Minimum [Member] | First Mortgage Bonds [Member] | Vectren [Member]
Debt Instruments [Abstract]
Interest rate of debt		2.375%
Acquired Long-term Debt [Abstract]
Interest rate of debt		2.375%
Minimum [Member] | Senior Notes Due Range 2 [Member] | Vectren [Member]
Debt Instruments [Abstract]
Interest rate of debt		3.33%
Acquired Long-term Debt [Abstract]
Interest rate of debt		3.33%
Maximum [Member] | VUHI [Member]
Acquired Long-term Debt [Abstract]
Basis spread on LIBOR		90.00%
Line of Credit Facility [Abstract]
Basis spread on LIBOR		90.00%
Maximum [Member] | Letter of Credit [Member] | Vectren [Member]
Line of Credit Facility [Abstract]
Long-term line of credit		$ 50
Maximum [Member] | First Mortgage Bonds [Member] | Vectren [Member]
Debt Instruments [Abstract]
Interest rate of debt		6.72%
Acquired Long-term Debt [Abstract]
Interest rate of debt		6.72%
Maximum [Member] | Senior Notes Due Range 2 [Member] | Vectren [Member]
Debt Instruments [Abstract]
Interest rate of debt		7.08%
Acquired Long-term Debt [Abstract]
Interest rate of debt		7.08%
[1]	This credit facility was issued by VCC, is guaranteed by Vectren and includes a $40 million swing line sublimit and an $80 million letter of credit sublimit.
[2]	This credit facility was issued by VUHI, is guaranteed by SIGECO, Indiana Gas and VEDO and includes a $10 million swing line sublimit and a $20 million letter of credit sublimit. This credit facility backstops VUHI’s commercial paper program.
[3]	This credit facility was issued by VCC and is guaranteed by Vectren.
[4]	CenterPoint Energy’s outstanding commercial paper generally has maturities of 60 days or less. Approximately $1.7 billion
[5]	This credit facility was issued by VUHI and is guaranteed by SIGECO, Indiana Gas and VEDO.
[6]	As defined in the revolving credit facility agreements, excluding Securitization Bonds.
[7]	Based on current credit ratings.
[8]	For CenterPoint Energy and Houston Electric, the financial covenant limit will temporarily increase from 65% to 70% if Houston Electric experiences damage from a natural disaster in its service territory and CenterPoint Energy certifies to the administrative agent that Houston Electric has incurred system restoration costs reasonably likely to exceed $100 million in a consecutive 12 -month period, all or part of which Houston Electric 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.
[9]	Represents borrowings under the VCC credit facility, which is guaranteed by Vectren.
[10]	Issued by VCC and guaranteed by Vectren. As of June 30, 2019, the term loan was fully drawn upon, exclusive of any potential incremental term loans under the related facility’s accordion feature. The term loan’s interest rate is currently priced at one -month LIBOR, plus a credit spread of 70 basis points.
[11]	The first mortgage bonds issued by SIGECO subject SIGECO’s properties to a lien under the related mortgage indenture. The first mortgage bonds have stated interest rates that range from 2.375% to 6.72% .
[12]	Issued by VUHI with maturities up to 30 days.
[13]	Consists of $532 million of senior notes issued by VUHI, $96 million of senior notes issues by Indiana Gas, and $9 million of senior notes issued by VCC. The senior notes have stated interest rates that range from 3.33% to 7.08% . The senior notes issued by VUHI are guaranteed by SIGECO, Indiana Gas and VEDO. The senior notes issued by VCC are guaranteed by Vectren. In connection with the Merger, two of CenterPoint Energy’s acquired wholly-owned subsidiaries, VUHI and VCC, made offers to prepay certain outstanding guaranteed senior notes as required pursuant to certain note purchase agreements previously entered into by VUHI and VCC. In turn, VUHI and VCC borrowed $568 million and $191 million , respectively, from CenterPoint Energy to fund note redemptions effected pursuant to these prepayment offers. To fund these prepayments and payments of approximately $5 million of accrued interest, CenterPoint Energy issued approximately $764 million of commercial paper.
[14]	Draw down by VCC on its variable rate term loan.
[15]	Issued by VUHI and guaranteed by SIGECO, Indiana Gas and VEDO. As of June 30, 2019, the term loan was fully drawn upon. The term loan’s interest rate is currently priced at one-month LIBOR, plus a credit spread ranging from 70 to 90 basis points depending on credit rating.

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Effective income tax rate	[1]	13.00%	15.00%	12.00%	27.00%
Net uncertain tax liability		$ 1		$ 1
Houston Electric [Member]
Effective income tax rate	[2]	19.00%	21.00%	19.00%	22.00%
Continuing Operations [Member] | CERC Corp [Member]
Effective income tax rate	[3]	0.00%	33.00%	14.00%	19.00%
Discontinued Operations [Member] | CERC Corp [Member]
Effective income tax rate	[4]		24.00%		24.00%
Federal statutory tax rate	[4]				21.00%
[1]	CenterPoint Energy’s lower effective tax rate for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to the following: an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators in certain jurisdictions; the impact of state tax law changes that resulted in the remeasurement of state deferred taxes; and the release of a valuation allowance on certain state net operating losses that are now expected to be utilized prior to expiration due to a current period law change.
[2]	Houston Electric’s lower effective tax rate for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators.
[3]	CERC’s lower effective tax rate on income from continuing operations for the three and six months ended June 30, 2019 compared to the same periods for 2018 was primarily due to the following: an increase in the amount of amortization of the net regulatory EDIT liability as decreed by regulators in certain jurisdictions; the impact of state tax law changes that resulted in the remeasurement of state deferred taxes; and the release of a valuation allowance on certain state net operating losses that are now expected to be utilized prior to expiration due to a current period law change. The state law changes and valuation allowance release resulted in a lower than expected effective tax rate for the three months ended June 30, 2019 as compared to the three months ended June 30, 2018.
[4]	CERC’s effective tax rate on income from discontinued operations for the three and six months ended June 30, 2018 was a result of the 21% federal income tax rate plus allocable state income taxes. There are no comparable periods in 2019 since the Internal Spin was completed in the third quarter of 2018.

Commitments and Contingencies_2

Commitments and Contingencies (Details)	6 Months Ended
	Jun. 30, 2019USD ($)surety_bondsite
Purchase Obligations
Remaining six months of 2019	$ 399,000,000
2020	658,000,000
2021	488,000,000
2022	576,000,000
2023	350,000,000
2024	228,000,000
2025 and beyond	$ 1,639,000,000
Performance Guarantees & Product Warranties [Abstract]
Number of surety bond obligations outstanding | surety_bond	68
Performance guarantee obligations outstanding face amount	$ 705,000,000
Percentage of work yet to be completed on projects with open surety bonds	40.00%
Guarantor obligations, maximum exposure, undiscounted	$ 489,000,000
Legal, Environmental and Other Matters
Asset retirement obligation	90,000,000
Minimum [Member]
Legal, Environmental and Other Matters
Estimated capital expenditure to clean ash ponds	60,000,000
Maximum [Member]
Legal, Environmental and Other Matters
Estimated capital expenditure to clean ash ponds	80,000,000
Minnesota Service Territory [Member]
Legal, Environmental and Other Matters
Liability recorded for environmental loss contingencies	7,000,000
Minnesota Service Territory [Member] | Minimum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites	$ 4,000,000
Years to resolve contingency	30 years
Minnesota Service Territory [Member] | Maximum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites	$ 32,000,000
Years to resolve contingency	50 years
Indiana Gas Service Territory [Member]
Legal, Environmental and Other Matters
Liability recorded for environmental loss contingencies	$ 2,000,000
Environmental remediation number of sites with potential remedial responsibility | site	26
CERC Corp [Member]
Purchase Obligations
Remaining six months of 2019	$ 276,000,000
2020	459,000,000
2021	308,000,000
2022	402,000,000
2023	197,000,000
2024	132,000,000
2025 and beyond	1,276,000,000
CERC Corp [Member] | Minnesota Service Territory [Member]
Legal, Environmental and Other Matters
Liability recorded for environmental loss contingencies	7,000,000
CERC Corp [Member] | Minnesota Service Territory [Member] | Minimum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites	$ 4,000,000
Years to resolve contingency	30 years
CERC Corp [Member] | Minnesota Service Territory [Member] | Maximum [Member]
Legal, Environmental and Other Matters
Estimated remediation costs for the Minnesota sites	$ 32,000,000
Years to resolve contingency	50 years
Minnehaha Academy Gas Explosion [Member]
Legal, Environmental and Other Matters
Contested amount of fines imposed	$ 200,000
Minnehaha Academy Gas Explosion [Member] | CERC Corp [Member]
Legal, Environmental and Other Matters
Contested amount of fines imposed	$ 200,000

Earnings Per Share (CenterPoi_3

Earnings Per Share (CenterPoint Energy) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Income (loss) available to common shareholders - basic		$ 165	$ (75)	$ 305	$ 90
Preferred stock dividend requirement		30	0	59	0
Net Income (Loss) Available to Common Stockholders, Diluted		$ 165	$ (75)	$ 305	$ 90
Denominator:
Weighted average common shares outstanding - basic		502,200,000	431,523,000	501,862,000	431,378,000
Weighted average common shares outstanding - diluted		504,831,000	431,523,000	504,493,000	434,407,000
Earnings per common share:
Basic earnings (loss) per common share		$ 0.33	$ (0.17)	$ 0.61	$ 0.21
Diluted earnings (loss) per common share		$ 0.33	$ (0.17)	$ 0.61	$ 0.21
Restricted Stock [Member]
Denominator:
Restricted stock (1)	[1]	2,631,000	0	2,631,000	3,029,000
Common Stock [Member]
Earnings per common share:
Amount of antidilutive shares excluded from computation of earnings per share			3,029,000
Series B Preferred Stock [Member]
Numerator:
Preferred stock dividend requirement		$ 0	$ 0	$ 0	$ 0
Denominator:
Series B Preferred Stock (2)	[2]	0	0	0	0
Earnings per common share:
Amount of antidilutive shares excluded from computation of earnings per share		32,121,000		32,121,000
[1]	The potentially dilutive impact from restricted stock awards applies the treasury stock method. Under this method, an increase in the average fair market value of Common Stock can result in a greater dilutive impact from these securities. 3,029,000 incremental shares from assumed conversions of restricted stock have not been included in the computation of diluted earnings (loss) per share for the three months ended June 30, 2018, as their inclusion would be anti-dilutive.
[2]	The potentially dilutive impact from Series B Preferred Stock applies the if-converted method in calculating diluted earnings per common share. Under this method, diluted earnings per common share is adjusted for the more dilutive effect of the Series B Preferred Stock as a result of either its accumulated dividend for the period in the numerator or the assumed-converted common share equivalent in the denominator. The computation of diluted earnings per common share outstanding for the three and six months ended June 30, 2019 excludes 32,121,000 and 32,121,000 potentially dilutive shares, respectively, because to include them would be anti-dilutive. However, these shares could be potentially dilutive in the future.

Reportable Business Segments (D

Reportable Business Segments (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenues		$ 2,798	$ 2,186	$ 6,329	$ 5,341
Operating Income (Loss)		287	187	532	438
Equity in earnings from investment in Enable		74	58	136	127
Assets		34,189		34,189		$ 27,009
Total regulatory assets		2,248		2,248		2,044
Houston Electric T&D [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	765	854	1,454	1,605
Operating Income (Loss)		169	181	253	296
Houston Electric T&D [Member] | Affiliates of NRG Energy, Inc. [Member]
Segment Reporting Information [Line Items]
Revenues		165	169	316	330
Houston Electric T&D [Member] | Affiliates of Vistra Energy Corp. [Member]
Segment Reporting Information [Line Items]
Revenues		59	59	113	113
Indiana Electric Integrated [Member]
Segment Reporting Information [Line Items]
Revenues		140	0	223	0
Operating Income (Loss)		25	0	16	0
Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Revenues		650	487	2,039	1,630
Operating Income (Loss)		47	7	214	163
Energy Services [Member]
Segment Reporting Information [Line Items]
Revenues		838	841	2,020	2,098
Operating Income (Loss)		29	15	62	(11)
Infrastructure Services [Member]
Segment Reporting Information [Line Items]
Revenues		325	0	471	0
Operating Income (Loss)		24	0	8	0
Midstream Investments [Member]
Segment Reporting Information [Line Items]
Revenues	[2]	0	0	0	0
Operating Income (Loss)	[2]	0	0	0	0
Equity in earnings from investment in Enable		74	58	136	127
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues		80	4	122	8
Operating Income (Loss)		(7)	(16)	(21)	(10)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues		(28)	(27)	(102)	(65)
Assets		(2,982)		(2,982)		(652)
Intersegment Eliminations [Member] | Houston Electric T&D [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	0	0
Intersegment Eliminations [Member] | Indiana Electric Integrated [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	0	0
Intersegment Eliminations [Member] | Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Revenues		(10)	(8)	(20)	(18)
Intersegment Eliminations [Member] | Energy Services [Member]
Segment Reporting Information [Line Items]
Revenues		(17)	(19)	(81)	(47)
Intersegment Eliminations [Member] | Infrastructure Services [Member]
Segment Reporting Information [Line Items]
Revenues		(1)	0	(1)	0
Intersegment Eliminations [Member] | Midstream Investments [Member]
Segment Reporting Information [Line Items]
Revenues	[2]	0	0	0	0
Intersegment Eliminations [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	0	0
Operating Segments [Member] | Houston Electric T&D [Member]
Segment Reporting Information [Line Items]
Assets		11,478		11,478		10,509
Operating Segments [Member] | Indiana Electric Integrated [Member]
Segment Reporting Information [Line Items]
Assets	[3]	2,989		2,989		0
Operating Segments [Member] | Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Assets	[3]	12,946		12,946		6,956
Operating Segments [Member] | Energy Services [Member]
Segment Reporting Information [Line Items]
Assets		1,262		1,262		1,558
Operating Segments [Member] | Infrastructure Services [Member]
Segment Reporting Information [Line Items]
Assets	[3]	1,303		1,303		0
Operating Segments [Member] | Midstream Investments [Member]
Segment Reporting Information [Line Items]
Assets		2,915		2,915		2,482
Operating Segments [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Assets	[3],[4]	4,278		4,278		6,156
Pension and Other Postretirement Plans Costs [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Total regulatory assets		639		639		665
Houston Electric [Member]
Segment Reporting Information [Line Items]
Revenues		765	854	1,451	1,609
Operating Income (Loss)		169	181	250	300
Assets		11,478		11,478		10,507
Total regulatory assets		1,016		1,016		1,124
Houston Electric [Member] | Houston Electric T&D [Member] | Affiliates of NRG Energy, Inc. [Member]
Segment Reporting Information [Line Items]
Revenues		0	169	0	330
Houston Electric [Member] | Houston Electric T&D [Member] | Affiliates of Vistra Energy Corp. [Member]
Segment Reporting Information [Line Items]
Revenues		0	59	0	113
CERC Corp [Member]
Segment Reporting Information [Line Items]
Revenues		1,342	1,328	3,710	3,728
Operating Income (Loss)		58	22	254	153
Assets		7,815		7,815		8,214
Total regulatory assets		207		207		258
CERC Corp [Member] | Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Revenues		503	487	1,688	1,630
Operating Income (Loss)		28	7	192	163
CERC Corp [Member] | Energy Services [Member]
Segment Reporting Information [Line Items]
Revenues		839	841	2,021	2,098
Operating Income (Loss)		29	15	62	(11)
CERC Corp [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	1	0
Operating Income (Loss)		1	0	0	1
CERC Corp [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues		(26)	(27)	(100)	(65)
Assets		(398)		(398)		(366)
CERC Corp [Member] | Intersegment Eliminations [Member] | Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Revenues		(10)	(8)	(20)	(18)
CERC Corp [Member] | Intersegment Eliminations [Member] | Energy Services [Member]
Segment Reporting Information [Line Items]
Revenues		(16)	(19)	(80)	(47)
CERC Corp [Member] | Intersegment Eliminations [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues		0	$ 0	0	$ 0
CERC Corp [Member] | Operating Segments [Member] | Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Assets		6,843		6,843		6,956
CERC Corp [Member] | Operating Segments [Member] | Energy Services [Member]
Segment Reporting Information [Line Items]
Assets		1,262		1,262		1,558
CERC Corp [Member] | Operating Segments [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Assets	[3]	$ 108		$ 108		66
Cash and Cash Equivalents [Member]
Segment Reporting Information [Line Items]
Short-term Investments						$ 3,900
[1]	Houston Electric T&D revenues from major external customers are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Affiliates of NRG $ 165 $ 169 $ 316 $ 330 Affiliates of Vistra Energy Corp. 59 59 113 113
[2]	CenterPoint Energy’s Midstream Investments’ equity earnings, net are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in millions) Enable $ 74 $ 58 $ 136 $ 127
[3]	Total assets by reportable segment include assets acquired in the Merger, which are based on preliminary estimates and allocations and are subject to change. See Note 3.
[4]	Includes pension and other postemployment-related regulatory assets of $639 million and $665 million , respectively, as of June 30, 2019 and December 31, 2018 . Additionally, total assets as of December 31, 2018 included $3.9 billion of temporary investments included in Cash and cash equivalents on CenterPoint Energy’s Consolidated Balance Sheets.

Supplemental Disclosure of Ca_3

Supplemental Disclosure of Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019		Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Interest, net of capitalized interest	$ 231		$ 167
Income taxes (refunds), net	142		88
Accounts payable related to capital expenditures	173		133
ROU assets obtained in exchange for lease liabilities (1)	42	[1]	0
Cash and cash equivalents	271			$ 4,231
Total cash, cash equivalents and restricted cash shown in Condensed Statements of Consolidated Cash Flows	332		366	4,278	$ 296
Prepaid expenses and other current assets [Member]
Restricted cash	61			46
Other [Member]
Restricted cash	0			1
Houston Electric [Member]
Interest, net of capitalized interest	113		90
Income taxes (refunds), net	73		120
Accounts payable related to capital expenditures	86		75
ROU assets obtained in exchange for lease liabilities (1)	1	[1]	0
Cash and cash equivalents	260			335
Total cash, cash equivalents and restricted cash shown in Condensed Statements of Consolidated Cash Flows	293		291	370	274
Houston Electric [Member] | Prepaid expenses and other current assets [Member]
Restricted cash	33			34
Houston Electric [Member] | Other [Member]
Restricted cash	0			1
CERC Corp [Member]
Interest, net of capitalized interest	55		50
Income taxes (refunds), net	3		3
Accounts payable related to capital expenditures	72		69
ROU assets obtained in exchange for lease liabilities (1)	28	[1]	0
Cash and cash equivalents	1			14
Total cash, cash equivalents and restricted cash shown in Condensed Statements of Consolidated Cash Flows	5		$ 1	25	$ 12
CERC Corp [Member] | Prepaid expenses and other current assets [Member]
Restricted cash	4			11
CERC Corp [Member] | Other [Member]
Restricted cash	$ 0			$ 0
[1]	Includes the transition impact of adoption of ASU 2016-02 Leases.

Related Party Transactions (H_3

Related Party Transactions (Houston Electric and CERC) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Houston Electric [Member]
Related Party Transaction [Line Items]
Interest income (expense) (1)	[1]	$ 6	$ 0	$ 9	$ 0
Cash dividends paid to parent		16	31	40	63
Cash contribution from parent		0	0	590	0
Houston Electric [Member] | Operation and maintenance expense [Member]
Related Party Transaction [Line Items]
Net affiliate service charges (billings)		(2)	(3)	(4)	(5)
Houston Electric [Member] | CenterPoint Energy [Member] | Operation and maintenance expense [Member]
Related Party Transaction [Line Items]
Corporate service charges		42	47	94	91
CERC Corp [Member]
Related Party Transaction [Line Items]
Interest income (expense) (1)	[1]	1	0	2	(2)
Cash dividends paid to parent		83	125	103	211
Cash contribution from parent		0	0	0	0
CERC Corp [Member] | Operation and maintenance expense [Member]
Related Party Transaction [Line Items]
Net affiliate service charges (billings)		2	3	4	5
CERC Corp [Member] | CenterPoint Energy [Member] | Operation and maintenance expense [Member]
Related Party Transaction [Line Items]
Corporate service charges		$ 32	$ 35	$ 75	$ 69
Investments [Member] | Houston Electric [Member]
Related Party Transaction [Line Items]
Weighted average interest rate		2.67%		2.67%		2.42%
Investments [Member] | CERC Corp [Member]
Related Party Transaction [Line Items]
Weighted average interest rate		2.67%		2.67%		2.42%
Accounts and notes receivable (payable) - affiliate companies [Member] | Houston Electric [Member]
Related Party Transaction [Line Items]
Money pool investments (borrowings) (1)	[2]	$ 794		$ 794
Money Pool Borrowings	[2]					$ 1
Accounts and notes receivable (payable) - affiliate companies [Member] | CERC Corp [Member]
Related Party Transaction [Line Items]
Money pool investments (borrowings) (1)	[2]	$ 180		$ 180		$ 114
[1]	Interest income is included in Other income (expense), net and interest expense is included in Interest and other finance charges on Houston Electric’s and CERC’s respective Condensed Statements of Consolidated Income.
[2]	Included in Accounts and notes receivable (payable)–affiliated companies on Houston Electric’s and CERC’s respective Condensed Consolidated Balance Sheets.

Leases (Details)

Leases (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
		Jun. 30, 2019	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Lease, Cost [Abstract]
Operating lease cost		$ 7	$ 11
Short-term lease cost		18	23
Total lease cost		25	34
Assets and Liabilities, Lessee [Abstract]
Operating ROU assets (1)	[1]	72	72
Lease Right-Of-Use Asset		72	72	$ 30
Current operating lease liability (2)	[2]	22	22
Non-current operating lease liability (3)	[3]	$ 50	$ 50
Weighted-average remaining lease term (in years) - operating leases		5 years 2 months 12 days	5 years 2 months 12 days
Weighted-average discount rate - operating leases		3.41%	3.41%
Operating Lease Liabilities, Payments Due [Abstract]
Remaining six months of 2019		$ 14	$ 14
2020		21	21
2021		15	15
2022		8	8
2023		7	7
2024		3	3
2025 and beyond		12	12
Total lease payments		80	80
Less: Interest		8	8
Present value of lease liabilities		72	72
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months					$ 6
Operating Leases, Future Minimum Payments, Due in Two Years					6
Operating Leases, Future Minimum Payments, Due in Three Years					5
Operating Leases, Future Minimum Payments, Due in Four Years					4
Operating Leases, Future Minimum Payments, Due in Five Years					3
Operating Leases, Future Minimum Payments, Due Thereafter					12
Operating Leases, Future Minimum Payments Due	[4]				36
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year		2	2
Lessor, Operating Lease, Payments to be Received, Next Twelve Months		2	2
Lessor, Operating Lease, Payments to be Received, Two Years		2	2
Lessor, Operating Lease, Payments to be Received, Three Years		2	2
Lessor, Operating Lease, Payments to be Received, Four Years		2	2
Lessor, Operating Lease, Payments to be Received, Five Years		2	2
Lessor, Operating Lease, Payments to be Received, Thereafter		10	10
Lessor, Operating Lease, Payments to be Received		22	22
Other Information Related to Leases [Abstract]
Operating Lease, Payments		7	12
Houston Electric [Member]
Lease, Cost [Abstract]
Operating lease cost		0	0
Short-term lease cost		3	5
Total lease cost		3	5
Assets and Liabilities, Lessee [Abstract]
Operating ROU assets (1)	[1]	1	1
Lease Right-Of-Use Asset		1	1	1
Current operating lease liability (2)	[2]	0	0
Non-current operating lease liability (3)	[3]	$ 1	$ 1
Weighted-average remaining lease term (in years) - operating leases		5 years 6 months	5 years 6 months
Weighted-average discount rate - operating leases		3.51%	3.51%
Operating Lease Liabilities, Payments Due [Abstract]
Remaining six months of 2019		$ 0	$ 0
2020		1	1
2021		0	0
2022		0	0
2023		0	0
2024		0	0
2025 and beyond		0	0
Total lease payments		1	1
Less: Interest		0	0
Present value of lease liabilities		1	1
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months					1
Operating Leases, Future Minimum Payments, Due in Two Years					0
Operating Leases, Future Minimum Payments, Due in Three Years					0
Operating Leases, Future Minimum Payments, Due in Four Years					0
Operating Leases, Future Minimum Payments, Due in Five Years					0
Operating Leases, Future Minimum Payments, Due Thereafter					0
Operating Leases, Future Minimum Payments Due	[4]				1
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year		0	0
Lessor, Operating Lease, Payments to be Received, Next Twelve Months		1	1
Lessor, Operating Lease, Payments to be Received, Two Years		0	0
Lessor, Operating Lease, Payments to be Received, Three Years		0	0
Lessor, Operating Lease, Payments to be Received, Four Years		0	0
Lessor, Operating Lease, Payments to be Received, Five Years		0	0
Lessor, Operating Lease, Payments to be Received, Thereafter		0	0
Lessor, Operating Lease, Payments to be Received		1	1
Other Information Related to Leases [Abstract]
Operating Lease, Payments		0	1
CERC Corp [Member]
Lease, Cost [Abstract]
Operating lease cost		2	3
Short-term lease cost		0	0
Total lease cost		2	3
Assets and Liabilities, Lessee [Abstract]
Operating ROU assets (1)	[1]	26	26
Lease Right-Of-Use Asset		26	26	$ 27
Current operating lease liability (2)	[2]	5	5
Non-current operating lease liability (3)	[3]	$ 21	$ 21
Weighted-average remaining lease term (in years) - operating leases		8 years 1 month 6 days	8 years 1 month 6 days
Weighted-average discount rate - operating leases		3.67%	3.67%
Operating Lease Liabilities, Payments Due [Abstract]
Remaining six months of 2019		$ 3	$ 3
2020		5	5
2021		4	4
2022		4	4
2023		3	3
2024		2	2
2025 and beyond		9	9
Total lease payments		30	30
Less: Interest		4	4
Present value of lease liabilities		26	26
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months					5
Operating Leases, Future Minimum Payments, Due in Two Years					5
Operating Leases, Future Minimum Payments, Due in Three Years					4
Operating Leases, Future Minimum Payments, Due in Four Years					4
Operating Leases, Future Minimum Payments, Due in Five Years					3
Operating Leases, Future Minimum Payments, Due Thereafter					11
Operating Leases, Future Minimum Payments Due	[4]				$ 32
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year		0	0
Lessor, Operating Lease, Payments to be Received, Next Twelve Months		0	0
Lessor, Operating Lease, Payments to be Received, Two Years		0	0
Lessor, Operating Lease, Payments to be Received, Three Years		0	0
Lessor, Operating Lease, Payments to be Received, Four Years		0	0
Lessor, Operating Lease, Payments to be Received, Five Years		0	0
Lessor, Operating Lease, Payments to be Received, Thereafter		0	0
Lessor, Operating Lease, Payments to be Received		0	0
Other Information Related to Leases [Abstract]
Operating Lease, Payments		$ 1	$ 2
[1]	Reported within Other assets in the Condensed Consolidated Balance Sheets.
[2]	Reported within Current other liabilities in the Condensed Consolidated Balance Sheets.
[3]	Reported within Other liabilities in the Condensed Consolidated Balance Sheets.
[4]	The Merger was completed on February 1, 2019. As such, these amounts are exclusive of Vectren’s leases.

Equity (Details)

Equity (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Class of Stock [Line Items]
Dividends declared per share		$ 0.2875		$ 0.2775		$ 0.2875	$ 0.2775
Preferred stock dividend requirement		$ 30		$ 0		$ 59	$ 0
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance		(107)	$ (108)	(63)	$ (68)	(108)	(68)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax	[1]	1		1		1	1
Actuarial losses	[1]	2		1		4	3
Reclassification of deferred loss from cash flow hedges realized in net income						1	0
Tax expense		(1)		0		(2)	(2)
Net current period other comprehensive income (loss)		2		1		3	6
Ending Balance		$ (105)	(107)	$ (62)	(63)	$ (105)	$ (62)
Common Stock [Member]
Class of Stock [Line Items]
Dividends declared per share		$ 0.2875		$ 0.2775		$ 0.2875	$ 0.2775
Dividends paid per share						$ 0.5750	$ 0.5550
Total dividends paid						$ 288	$ 240
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividends declared		$ 0		$ 0		$ 0	$ 0
Dividends paid per share						$ 32.1563
Total dividends paid						$ 26
Preferred stock dividend requirement		$ 13		$ 0		$ 25	$ 0
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividends declared		$ 17.5000		$ 0		$ 17.5000	$ 0
Dividends paid per share						$ 35
Total dividends paid						$ 34
Preferred stock dividend requirement		$ 17		$ 0		34	$ 0
Houston Electric [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance		(15)	(14)	4	0	(14)	0
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax	[1]	0		0		0	0
Actuarial losses	[1]	0		0		0	0
Reclassification of deferred loss from cash flow hedges realized in net income						0	0
Tax expense		0		0		0	(1)
Net current period other comprehensive income (loss)		0		0		(1)	4
Ending Balance		(15)	(15)	4	4	(15)	4
CERC Corp [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance		5	5	6	6	5	6
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax	[1]	0		0		0	0
Actuarial losses	[1]	0		0		0	0
Reclassification of deferred loss from cash flow hedges realized in net income						0	0
Tax expense		0		0		0	0
Net current period other comprehensive income (loss)		0		0		0	0
Ending Balance		5	$ 5	6	$ 6	5	6
Interest Rate Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income (loss) before reclassifications	[2]	0		(1)		(1)	4
Interest Rate Contract [Member] | Houston Electric [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income (loss) before reclassifications	[2]	0		0		(1)	5
Interest Rate Contract [Member] | CERC Corp [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income (loss) before reclassifications	[2]	$ 0		$ 0		$ 0	$ 0
First Quarter 2019 [Member] | Common Stock [Member]
Class of Stock [Line Items]
Declaration Date			Dec. 12, 2018
Record Date			Feb. 21, 2019
Payment Date			Mar. 14, 2019
Dividends paid per share			$ 0.2875
Total dividends paid			$ 144
First Quarter 2019 [Member] | Series A Preferred Stock [Member]
Class of Stock [Line Items]
Declaration Date			Dec. 12, 2018
Record Date			Feb. 15, 2019
Payment Date			Mar. 1, 2019
Dividends paid per share			$ 32.1563
Total dividends paid			$ 26
First Quarter 2019 [Member] | Series B Preferred Stock [Member]
Class of Stock [Line Items]
Declaration Date			Dec. 12, 2018
Record Date			Feb. 15, 2019
Payment Date			Mar. 1, 2019
Dividends paid per share			$ 17.5000
Total dividends paid			$ 17
Second Quarter 2019 [Member] | Common Stock [Member]
Class of Stock [Line Items]
Declaration Date		Apr. 25, 2019
Record Date		May 16, 2019
Payment Date		Jun. 13, 2019
Dividends paid per share		$ 0.2875
Total dividends paid		$ 144
Second Quarter 2019 [Member] | Series B Preferred Stock [Member]
Class of Stock [Line Items]
Declaration Date		Apr. 25, 2019
Record Date		May 15, 2019
Payment Date		Jun. 3, 2019
Dividends paid per share		$ 17.5000
Total dividends paid		$ 17
First Quarter 2018 [Member] | Common Stock [Member]
Class of Stock [Line Items]
Declaration Date					Dec. 13, 2017
Record Date					Feb. 15, 2018
Payment Date					Mar. 8, 2018
Dividends paid per share					$ 0.2775
Total dividends paid					$ 120
Second Quarter 2018 [Member] | Common Stock [Member]
Class of Stock [Line Items]
Declaration Date				Apr. 26, 2018
Record Date				May 17, 2018
Payment Date				Jun. 14, 2018
Dividends paid per share				$ 0.2775
Total dividends paid				$ 120
[1]	Amounts are included in the computation of net periodic cost and are reflected in Other income (expense), net in each of the Registrants’ respective Statements of Consolidated Income.
[2]	Gains and losses are reclassified from Accumulated other comprehensive income into income when the hedged transactions affect earnings. The reclassification amounts are included in Interest and other finance charges in each of the Registrants’ respective Statements of Consolidated Income. Over the next twelve months estimated amortization from Accumulated Comprehensive Income into income is expected to be immaterial.

Subsequent Events (CenterPoin_3

Subsequent Events (CenterPoint Energy) (Details) - USD ($) $ / shares in Units, $ in Millions

Sep. 12, 2019

Sep. 03, 2019

Aug. 27, 2019

Aug. 20, 2019

Aug. 19, 2019

Aug. 14, 2019

Aug. 02, 2019

Jul. 31, 2019

Jun. 30, 2019

Jun. 30, 2018

Jun. 30, 2019

Jun. 30, 2018

Subsequent Event [Line Items]

Dividends declared per share

$ 0.2875

$ 0.2775

$ 0.2875

$ 0.2775

Common Stock [Member]

Subsequent Event [Line Items]

Dividends declared per share

0.2875

0.2775

0.2875

0.2775

Series A Preferred Stock [Member]

Subsequent Event [Line Items]

Series B Preferred Stock dividends declared ($17.5000, $-0-, $17.5000, and $-0- per share, respectively)

0

0

0

0

Series B Preferred Stock [Member]

Subsequent Event [Line Items]

Series B Preferred Stock dividends declared ($17.5000, $-0-, $17.5000, and $-0- per share, respectively)

$ 17.5000

$ 0

$ 17.5000

$ 0

Subsequent Event [Member] | Common Stock [Member]

Subsequent Event [Line Items]

Dividends payable, date declared

Jul. 31, 2019

Dividends payable, date of record

Aug. 15, 2019

Dividends payable, date to be paid

Sep. 12, 2019

Dividends declared per share

$ 0.2875

Subsequent Event [Member] | Series A Preferred Stock [Member]

Subsequent Event [Line Items]

Dividends payable, date declared

Jul. 31, 2019

Dividends payable, date of record

Aug. 15, 2019

Dividends payable, date to be paid

Sep. 3, 2019

Series B Preferred Stock dividends declared ($17.5000, $-0-, $17.5000, and $-0- per share, respectively)

$ 30.6250

Subsequent Event [Member] | Series B Preferred Stock [Member]

Subsequent Event [Line Items]

Dividends payable, date declared

Jul. 31, 2019

Dividends payable, date of record

Aug. 15, 2019

Dividends payable, date to be paid

Sep. 3, 2019

Series B Preferred Stock dividends declared ($17.5000, $-0-, $17.5000, and $-0- per share, respectively)

$ 17.5000

Common Units [Member] | Subsequent Event [Member] | Enable Midstream Partners [Member]

Subsequent Event [Line Items]

Quarterly cash distribution, declaration date

Aug. 2, 2019

Quarterly cash distribution, date of record

Aug. 20, 2019

Quarterly cash distribution, distribution date

Aug. 27, 2019

Quarterly cash distribution declared per share

$ 0.3305

Expected cash distribution from equity method investment

$ 77

Series A Preferred Units [Member] | Subsequent Event [Member] | Enable Midstream Partners [Member]

Subsequent Event [Line Items]

Quarterly cash distribution, declaration date

Aug. 2, 2019

Quarterly cash distribution, date of record

Aug. 2, 2019

Quarterly cash distribution, distribution date

Aug. 14, 2019

Quarterly cash distribution declared per share

$ 0.6250

Expected cash distribution from cost method investment

$ 9