Debt Instrument, Additional Interest Accrual, Maximum Rate Per Year

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- Definition

Debt Instrument, Additional Interest Accrual, Rate For First Ninety Days

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Debt Instrument, Additional Interest Accrual, Rate For Subsequent Ninety Days

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- Definition

Debt Instrument, Convertible, Business Days

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- Definition

Debt Instrument Convertible, Conversion Price, Premium

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- Definition

Debt Instrument, Convertible, Repurchase Price, Percentage Of Principal Amount

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- Definition

Debt Instrument, Convertible, Threshold Trading Days, Measurement Period

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Debt Instrument, Measurement Period Percentage

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- Definition

Effective Shelf Registration, Effective Period

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Minimum Equity To Total Capitalization Ratio To Be Maintained For Payment Of Capital Dividend

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- Definition

Number Of Subsidiaries That Issued Environmental Control Bonds

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- Definition

Preference Stock Shares Outstanding.

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- Definition

Principal Default Amount Specified In Debt Covenants.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Amount of tax expense (benefit) on gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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CAPITALIZATION - Narrative (Details) $ / shares in Units, $ in Millions				12 Months Ended
	Mar. 25, 2024 USD ($)	May 04, 2023 USD ($) tradingDay	May 01, 2023	Dec. 31, 2024 USD ($) subsidiary $ / shares shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 shares	Dec. 05, 2024 USD ($)	Sep. 30, 2024	Sep. 05, 2024 USD ($)	Apr. 30, 2023	Jun. 30, 2013 USD ($)
Debt Instrument [Line Items]
FERC-defined equity to total capitalization ratio				35.00%
Preference shares outstanding (in shares) \| shares				0	0
Preferred shares, outstanding (in shares) \| shares				0	0
Number of subsidiaries that issued environmental control bonds \| subsidiary				2
Environmental control bonds outstanding				$ 188	$ 218
Principal default amount specified in debt covenants				$ 100
4.00%, $1,500 Million Notes Maturity 2026
Debt Instrument [Line Items]
Proceeds from issuance of debt		$ 1,480
2026 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, convertible, conversion ratio				0.021362
Phase In Recovery Bonds
Debt Instrument [Line Items]
Long-term debt and other long-term obligations				$ 175	$ 191
Unsecured Debt \| 2026 Convertible Notes
Debt Instrument [Line Items]
Issuance interest rate										4.00%
Registered Shareholders, Directors and Employees of Subsidiaries
Debt Instrument [Line Items]
Consolidated tax benefit allocation (in shares) \| shares				3,000,000	2,000,000	2,000,000
FET \| Senior Notes \| 5.15%, 300 Million Notes Maturing 2026
Debt Instrument [Line Items]
Face amount of loan									$ 400
FET \| Promissory Notes \| 4.55% Unsecured Senior Notes Maturing 2031
Debt Instrument [Line Items]
Face amount of loan									$ 400
Issuance interest rate								4.55%
FET \| Promissory Notes \| 5.15%, 300 Million Notes Maturing 2026
Debt Instrument [Line Items]
Issuance interest rate								5.00%
AGC
Debt Instrument [Line Items]
FERC-defined equity to total capitalization ratio				45.00%
JCP&L \| Promissory Notes \| 5.10% Unsecured Senior Notes Maturing 2035
Debt Instrument [Line Items]
Face amount of loan							$ 700
Effective shelf registration, effective period				60 days
Interest accrual rate for the first 90 days				0.25%
Additional interest accrual rate for subsequent 90 days				0.25%
Additional interest accrual maximum rate per year				0.50%
Issuance interest rate				5.10%
FE \| Promissory Notes \| 4.00%, $1,500 Million Notes Maturity 2026
Debt Instrument [Line Items]
Face amount of loan		$ 1,500
Debt instrument, convertible, threshold trading days \| tradingDay		20
Debt instrument, convertible, threshold consecutive trading days \| tradingDay		30
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Debt instrument, convertible, business days \| tradingDay		5
Threshold trading days measurement period \| tradingDay		10
Debt instrument, measurement period percentage		98.00%
Debt instrument, conversation price (in dollars per share) \| $ / shares				$ 46.81
Debt instrument convertible premium			0.20
Repurchase price, percentage			1
Ohio Funding Companies \| Phase In Recovery Bonds
Debt Instrument [Line Items]
Face amount of loan											$ 445
Brookfield II \| FET
Debt Instrument [Line Items]
Gain (loss) from disposal of discontinued operation	$ 7,000