Contribution From Parent

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- Definition

Money Pool Investments (Borrowings)

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of outstanding investments in money pool.

+ References

No definition available.

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- Definition

Amount of net service charges from (billings to) related party during the period, excluding transactions that are eliminated in consolidated or combined financial statements.

+ References

No definition available.

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- Definition

Payment Of Dividends To Parent

+ References

No definition available.

+ Details

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

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-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-3

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c)(2)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

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- Details

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- Details

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- Details

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Related Party Transactions (Houston Electric and CERC) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Houston Electric
Related Party Transaction [Line Items]
Money pool investments (borrowings), net	$ (71)		$ (71)		$ 238
Cash dividends paid to parent	94	$ 79	249	$ 239
Houston Electric \| Additional Paid-in-Capital
Related Party Transaction [Line Items]
Contribution from parent	94	235	324	885
Houston Electric \| Operation and maintenance expense
Related Party Transaction [Line Items]
Net affiliate service charges (billings)	(1)	(1)	(4)	(7)
Houston Electric \| Operation and maintenance expense \| CenterPoint Energy
Related Party Transaction [Line Items]
Corporate service charges	$ 45	40	$ 124	115
Houston Electric \| Investments
Related Party Transaction [Line Items]
Weighted average interest rate	4.98%		4.98%		5.59%
CERC
Related Party Transaction [Line Items]
Money pool investments (borrowings), net	$ 0		$ 0		$ 1
Cash dividends paid to parent	24	36	270	347
CERC \| Additional Paid-in-Capital
Related Party Transaction [Line Items]
Contribution from parent	0	0	290	500
CERC \| Operation and maintenance expense
Related Party Transaction [Line Items]
Net affiliate service charges (billings)	1	1	4	7
CERC \| Operation and maintenance expense \| CenterPoint Energy
Related Party Transaction [Line Items]
Corporate service charges	$ 50	$ 56	$ 156	$ 162
CERC \| Investments
Related Party Transaction [Line Items]
Weighted average interest rate	4.98%		4.98%		5.59%