Supplemental Disclosure of Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Interest, net of capitalized interest	$ 489	$ 471	$ 436
Income taxes (refunds), net	(46)	143	155
Accounts payable related to capital expenditures	370	153	236
ROU assets obtained in exchange for lease liabilities	2	15	44
Recognition of beneficial conversion feature	0	32	0
Amortization of beneficial conversion feature	0	(32)	0
Capital distribution associated with the Internal Spin	0	0	0
Cash and cash equivalents	230	147
Total cash, cash equivalents and restricted cash shown in Statements of Consolidated Cash Flows	254	167	271	$ 4,278
Energy Transfer Common Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	1,672	0	0
Energy Transfer Series G Preferred Units
Condensed Financial Statements, Captions [Line Items]
Fair value of units received	385	0	0
Prepaid Expenses and Other Current Assets
Condensed Financial Statements, Captions [Line Items]
Restricted cash	24	20
Houston Electric
Condensed Financial Statements, Captions [Line Items]
Interest, net of capitalized interest	208	201	229
Income taxes (refunds), net	20	65	87
Accounts payable related to capital expenditures	261	102	117
Fair value of units received	0	0	0
ROU assets obtained in exchange for lease liabilities	0	1	1
Recognition of beneficial conversion feature	0	0	0
Amortization of beneficial conversion feature	0	0	0
Capital distribution associated with the Internal Spin	0	0	0
Cash and cash equivalents	214	139
Total cash, cash equivalents and restricted cash shown in Statements of Consolidated Cash Flows	233	154	235	370
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
Houston Electric \| Prepaid Expenses and Other Current Assets
Condensed Financial Statements, Captions [Line Items]
Restricted cash	19	15
CERC Corp
Condensed Financial Statements, Captions [Line Items]
Interest, net of capitalized interest	99	114	109
Income taxes (refunds), net	4	4	7
Accounts payable related to capital expenditures	103	69	86
Fair value of units received	0	0	28
ROU assets obtained in exchange for lease liabilities	0	5	29
Recognition of beneficial conversion feature	0	0	0
Amortization of beneficial conversion feature	0	0	0
Capital distribution associated with the Internal Spin	0	0	28
Cash and cash equivalents	8	1
Total cash, cash equivalents and restricted cash shown in Statements of Consolidated Cash Flows	8	1	2	$ 25
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
CERC Corp \| Prepaid Expenses and Other Current Assets
Condensed Financial Statements, Captions [Line Items]
Restricted cash	0	0
Bond Companies \| Houston Electric
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	$ 92	$ 139

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