Debt Instrument, Subjective Acceleration Clause, Cross-Default, Amount

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- Definition

Line of Credit Facility, Covenant Compliance, Coverage Ratio

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Compliance, Debt to Capitalization Ratio, Percent

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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- Definition

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.

+ References

No definition available.

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

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SHORT-TERM BORROWINGS AND BANK LINES OF CREDIT - Narrative (Details) - USD ($)		12 Months Ended
	Oct. 24, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2021	Oct. 23, 2024
Short-term Debt [Line Items]
Short-term borrowings		$ 550,000,000	$ 775,000,000
Short-term debt, weighted average interest rate, at point in time (percent)		7.10%	6.96%
Maximum \| Money Pool
Short-term Debt [Line Items]
Debt term		364 days
Minimum \| Available for Issuance of Letters of Credit
Short-term Debt [Line Items]
Cross-default provision for other indebtedness		$ 100,000,000
Revolving Credit Facility \| Line of Credit
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	$ 1,000,000,000.0
Available liquidity		5,300,000,000
Revolving Credit Facility \| Line of Credit \| FE
Short-term Debt [Line Items]
Debt term	1 year
Maximum amount borrowed under revolving credit facility	$ 750,000,000				$ 500,000,000
Revolving Credit Facility \| Line of Credit \| FET
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	1,000,000,000.0
Revolving Credit Facility \| Line of Credit \| Ohio Companies
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	800,000,000
Revolving Credit Facility \| Line of Credit \| Pennsylvania Companies
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	950,000,000
Revolving Credit Facility \| Line of Credit \| JCP&L
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	750,000,000
Revolving Credit Facility \| Line of Credit \| MP and PE
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	400,000,000
Revolving Credit Facility \| Line of Credit \| Transmission companies
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	850,000,000
Revolving Credit Facility \| Line of Credit \| KATCo
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	$ 150,000,000
Revolving Credit Facility \| Line of Credit \| Parent, FET, the Utilities and the Transmission Companies \| Maximum
Short-term Debt [Line Items]
Debt term				364 days
Revolving Credit Facility \| Line of Credit \| FET, the Utilities and the Transmission Companies
Short-term Debt [Line Items]
Coverage ratio				250.00%
Revolving Credit Facility \| Line of Credit \| FET, the Utilities and the Transmission Companies \| Maximum
Short-term Debt [Line Items]
Consolidated debt to total capitalization ratio (percent)				75.00%
Revolving Credit Facility \| Line of Credit \| FET, the Utilities and the Transmission Companies \| Minimum
Short-term Debt [Line Items]
Consolidated debt to total capitalization ratio (percent)				65.00%
Letter of Credit \| Line of Credit
Short-term Debt [Line Items]
Debt term			1 year
Outstanding borrowings		170,000,000
Letter of Credit \| FE \| Line of Credit
Short-term Debt [Line Items]
Letters of credit outstanding, amount		$ 139,000,000