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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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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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ORGANIZATION AND BASIS OF PRESENTATION (Details) individual in Millions, customer in Millions, $ in Millions			3 Months Ended
	Mar. 24, 2025 USD ($) employee	Feb. 26, 2025 USD ($) transmission_project substation mi kV	Mar. 31, 2025 USD ($) customer individual transmissionCenter mi MW	Mar. 31, 2024 USD ($)	Feb. 21, 2025	Dec. 31, 2024 USD ($)
Regulatory Asset [Line Items]
Number of customers \| customer			6.0
Number of regional transmission centers \| transmissionCenter			2
Capitalized cost of equity			$ 22	$ 13
Capitalized interest			16	17
Equity method investment earnings, net (Note 1)			0	21
Organizational Changes
Regulatory Asset [Line Items]
Expected number of employees reassigned \| employee	200
Percentage of employees reduced from workforce	3.00%
Restructuring charges	$ 26
Valley Link
Regulatory Asset [Line Items]
Equity method investments			0			$ 0
Valley Link \| PJM
Regulatory Asset [Line Items]
Number of transmission projects \| transmission_project		2
Valley Link \| PJM \| Putnam County, West Virginia to Frederick, Maryland
Regulatory Asset [Line Items]
Service area \| mi		260
Transmission line electrical potential (in kV) \| kV		765
Number of substations \| substation		2
Valley Link \| PJM \| Campbell County, Virginia and Fauquier County, Virginia
Regulatory Asset [Line Items]
Service area \| mi		155
Transmission line electrical potential (in kV) \| kV		765
Valley Link \| PJM 2024 RTEP Window 1 \| PJM
Regulatory Asset [Line Items]
Transmission solutions to the reliability issues		$ 3,000
Global Holding
Regulatory Asset [Line Items]
Equity method investments			45			45
Path Wv \| Variable Interest Entity, Not Primary Beneficiary
Regulatory Asset [Line Items]
Equity method investments			$ 17			17
Variable interest entities percentage of high voltage transmission line project owned By variable interest entity one in joint venture party one			100.00%
Variable interest entities percentage of high voltage transmission line project owned by variable interest entity one in joint venture party two			50.00%
Other Sundry Investments
Regulatory Asset [Line Items]
Equity method investments			$ 85			84
Regulated Transmission
Regulatory Asset [Line Items]
Service area \| mi			24,000
Integrated Segment
Regulatory Asset [Line Items]
Plant capacity (in MW's) \| MW			3,604
VEPCO and Transource Energy, LLC \| Valley Link
Regulatory Asset [Line Items]
Equity method investments		3,000
JERSEY CENTRAL POWER & LIGHT COMPANY
Regulatory Asset [Line Items]
Number of customers \| customer			1.2
Transmission services available area populations \| individual			2.8
Capitalized cost of equity			$ 6	1
Capitalized interest			3	6
JERSEY CENTRAL POWER & LIGHT COMPANY \| Organizational Changes
Regulatory Asset [Line Items]
Restructuring charges			5
JERSEY CENTRAL POWER & LIGHT COMPANY \| Other Sundry Investments
Regulatory Asset [Line Items]
Equity method investments			$ 0			$ 0
Brookfield \| FET \| North American Transmission Company II LLC
Regulatory Asset [Line Items]
Equity method investment, ownership percentage			49.90%
FEV \| Global Holding
Regulatory Asset [Line Items]
Investment ownership percentage			33.33%
FEV \| Corporate and Other \| Global Holding \| Other Nonoperating Income (Expense)
Regulatory Asset [Line Items]
Equity method investment earnings, net (Note 1)				$ 21
FET \| Valley Link
Regulatory Asset [Line Items]
Equity method investment, ownership percentage					34.00%
FET \| Valley Link \| PJM 2024 RTEP Window 1 \| PJM
Regulatory Asset [Line Items]
Transmission solutions to the reliability issues		$ 1,020
Dominion HV \| Valley Link
Regulatory Asset [Line Items]
Equity method investment, ownership percentage					30.00%
Transource \| Valley Link
Regulatory Asset [Line Items]
Equity method investment, ownership percentage					36.00%