Consolidation, Less than Wholly Owned Subsidiary, Debt Covenants, Minimum Interest Ownership Interest

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Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Carrying Value of Noncontrolling Interest

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Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Sale of Interest by Parent, Percent

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Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Transaction Costs

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Investment, Ownership Percentage Pledged as Collateral

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- Definition

Length Of Transmission Lines

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Number Of Customers.

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Number of Directors

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Number of existing utility operating companies.

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Number Of Regional Transmission Centers

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Plant Capacity

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- Definition

Variable interest entities percentage of high voltage transmission line project owned By variable interest entity one in joint venture party one.

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No definition available.

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Variable Interest Entities Percentage of high voltage transmission line project owned By variable interest entity one in joint venture party two.

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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- Definition

Represents a sale by the parent of a portion of its equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The sale of the equity interest represented by this element does not result in a loss of control by the parent.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of interest capitalized during the period.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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Dividends received on equity and other investments during the current period.

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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.

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The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets.

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ORGANIZATION AND BASIS OF PRESENTATION - Narrative (Details) mi in Thousands, customer in Millions, $ in Millions			3 Months Ended		6 Months Ended
	Feb. 02, 2023 USD ($) director	May 31, 2022 USD ($)	Jun. 30, 2023 USD ($) company transmissionCenter MW	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) company customer transmissionCenter mi MW	Jun. 30, 2022 USD ($)	Apr. 27, 2023 USD ($)	Dec. 31, 2022 USD ($)
Property, Plant and Equipment [Line Items]
Length of transmission lines \| mi					24
Number of regional transmission centers \| transmissionCenter			2		2
Capitalized cost of equity			$ 11	$ 11	$ 19	$ 24
Capitalized interest			11	6	24	12
Equity method investment earnings			$ 35	65	$ 91	77
Regulated Distribution
Property, Plant and Equipment [Line Items]
Number of existing utility operating companies \| company			10		10
Number of customers served by utility operating companies \| customer					6
Plant capacity (in MW's) \| MW			3,580		3,580
North American Transmission Company II LLC \| FET
Property, Plant and Equipment [Line Items]
Sale of ownership interest by parent	30.00%						30.00%
Noncontrolling interest, ownership percentage by noncontrolling owners	49.90%
Global Holding
Property, Plant and Equipment [Line Items]
Equity method investments			$ 56		$ 56			$ 57
FET \| FirstEnergy
Property, Plant and Equipment [Line Items]
Equity method investment, ownership percentage	50.10%
Other Sundry Investments
Property, Plant and Equipment [Line Items]
Equity method investments			93		93			90
Path Wv \| Variable Interest Entity, Not Primary Beneficiary
Property, Plant and Equipment [Line Items]
Equity method investments			$ 18		$ 18			$ 18
Percentage of high-voltage transmission line project owned by subsidiary of FE on the Allegheny Series			100.00%		100.00%
Percentage of high-voltage transmission line project owned by subsidiary of FE on the West Virginia Series			50.00%		50.00%
FET
Property, Plant and Equipment [Line Items]
Net of transaction costs		$ 37
Carrying value of the noncontrolling interest		$ 451
Number of directors \| director	5
FET \| FirstEnergy
Property, Plant and Equipment [Line Items]
Number of directors \| director	3
FET \| North American Transmission Company II LLC
Property, Plant and Equipment [Line Items]
Sale of ownership interest by parent		19.90%
Sale price of ownership interest by parent		$ 2,375
Disposal group, including discontinued operation, consideration	$ 3,500						$ 3,500
Business combination, consideration transferred, liabilities incurred	$ 1,750
Number of directors \| director	2
Minimum ownership interest	30.00%
FEV \| Global Holding
Property, Plant and Equipment [Line Items]
Investment ownership percentage			33.30%		33.30%
Proceeds from dividends received					$ 90	70
FEV \| Global Holding \| Corporate and Other \| Other Nonoperating Income (Expense)
Property, Plant and Equipment [Line Items]
Equity method investment earnings			$ 35	$ 64	$ 89	$ 76