Supplemental Disclosure of Cash Flow and Balance Sheet Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Financial Statements, Captions [Line Items]
Interest, net of capitalized interest (under further review)	$ 664	$ 480	$ 489
Income tax payments (refunds), net	215	421	(46)
Accounts payable related to capital expenditures	246	335	370
ROU assets obtained in exchange for lease liabilities	3	7	2
Restricted cash included in Prepaid expenses and other current assets	$ 90	$ 74
Restricted Cash and Cash Equivalents, Statement of Financial Position [Extensible Enumeration]	Prepaid expenses and other current assets ($15 and $13 related to VIEs, respectively)	Prepaid expenses and other current assets ($15 and $13 related to VIEs, respectively)
Restricted cash included in Prepaid expenses and other current assets	$ 19	$ 17
Total cash, cash equivalents and restricted cash shown in Statements of Consolidated Cash Flows	109	91	254	$ 167
Recovery of Extraordinary Gas Costs
Condensed Financial Statements, Captions [Line Items]
Income taxes paid	215
Energy Transfer Common Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	0	0	1,672
Energy Transfer Series G Preferred Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	0	0	385
Houston Electric
Condensed Financial Statements, Captions [Line Items]
Interest, net of capitalized interest (under further review)	287	223	208
Income tax payments (refunds), net	12	142	20
Accounts payable related to capital expenditures	166	168	261
Fair value of units received	0	38	0
ROU assets obtained in exchange for lease liabilities	1	6	0
Restricted cash included in Prepaid expenses and other current assets	76	75
Restricted cash included in Prepaid expenses and other current assets	13	13
Total cash, cash equivalents and restricted cash shown in Statements of Consolidated Cash Flows	89	88	233	154
Houston Electric \| Other Current Liabilities
Condensed Financial Statements, Captions [Line Items]
Contributions in aid of construction	47	35
Houston Electric \| Energy Transfer Common Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	0	0	0
Houston Electric \| Energy Transfer Series G Preferred Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	0	0	0
CERC Corp
Condensed Financial Statements, Captions [Line Items]
Interest, net of capitalized interest (under further review)	175	104	130
Income tax payments (refunds), net	115	37	(7)
Accounts payable related to capital expenditures	74	139	128
Fair value of units received	0	54	0
ROU assets obtained in exchange for lease liabilities	0	0	0
Restricted cash included in Prepaid expenses and other current assets	1	0
Restricted cash included in Prepaid expenses and other current assets	0	0
Total cash, cash equivalents and restricted cash shown in Statements of Consolidated Cash Flows	1	0	15	$ 6
CERC Corp \| Credits Related to Customers on Budget Billing Programs
Condensed Financial Statements, Captions [Line Items]
Contract with customer, liability, current, budget billing programs	118	61
CERC Corp \| Energy Transfer Common Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	0	0	0
CERC Corp \| Energy Transfer Series G Preferred Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	0	0	$ 0
Bond Companies \| Houston Electric
Condensed Financial Statements, Captions [Line Items]
Restricted cash included in Prepaid expenses and other current assets	76	75
Bond Companies and Securitization Bond Company
Condensed Financial Statements, Captions [Line Items]
Restricted cash included in Prepaid expenses and other current assets	$ 90	$ 75

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Developers, builders, governmental agencies and municipalities will provide the entity with cash, or in some cases property, to extend its services to their properties. Nonrefundable contributions are recorded as contributions in aid of construction ("CIAC").

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The value of the noncash (or part noncash) consideration given (for example, liability, equity) in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

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