Debt Instrument, Number of Agreements

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- Definition

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

+ References

No definition available.

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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

+ References

No definition available.

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- Definition

Short-Term Borrowings and Bank Lines of Credit.

+ References

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.

+ References

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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

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.

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- Definition

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

+ References

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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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

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)			12 Months Ended
	Oct. 18, 2021 USD ($) agreement	Nov. 23, 2020 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Short-term borrowings			$ 0	$ 2,200,000,000
Average interest rate for borrowings			2.42%	1.86%
Revolving Credit Facility \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Line of credit facility, remaining borrowing capacity			$ 4,500,000,000
Number of agreements \| agreement	6
Maximum amount borrowed under revolving credit facility	$ 4,500,000,000
Revolving Credit Facility \| Parent, FET, the Utilities and the Transmission Companies \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Term of revolving credit facility	5 years
Revolving Credit Facility \| Parent, FET, the Utilities and the Transmission Companies \| Line of Credit \| Maximum
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Term of revolving credit facility			364 days
Revolving Credit Facility \| Parent and FET \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Maximum amount borrowed under revolving credit facility	$ 1,000,000,000.0
Revolving Credit Facility \| Ohio Companies \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Maximum amount borrowed under revolving credit facility	800,000,000
Revolving Credit Facility \| Pennsylvania Companies \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Maximum amount borrowed under revolving credit facility	950,000,000
Revolving Credit Facility \| JCP&L \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Maximum amount borrowed under revolving credit facility	500,000,000
Revolving Credit Facility \| MP and PE \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Maximum amount borrowed under revolving credit facility	400,000,000
Revolving Credit Facility \| Transmission companies \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Maximum amount borrowed under revolving credit facility	$ 850,000,000
Revolving Credit Facility \| FET, the Utilities and the Transmission Companies \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Coverage ratio			250.00%
Revolving Credit Facility \| FET, the Utilities and the Transmission Companies \| Line of Credit \| Minimum
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Consolidated debt to total capitalization ratio (percent)			65.00%
Revolving Credit Facility \| FET, the Utilities and the Transmission Companies \| Line of Credit \| Maximum
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Consolidated debt to total capitalization ratio (percent)			75.00%
Revolving Credit Facility \| FET \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Line of credit facility, remaining borrowing capacity		$ 0
Revolving Credit Facility \| FE and the regulated distribution subsidiaries \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Proceeds from lines of credit		950,000,000
Line of Credit \| Letter of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Term of revolving credit facility			1 year
Money Pool \| Maximum
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Term of revolving credit facility			364 days
Money Pool \| Regulated Companies
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Average interest rate for borrowings			1.01%
Money Pool \| Unregulated Companies
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Average interest rate for borrowings			0.60%
Available for Issuance of Letters of Credit \| Minimum
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Cross-default provision for other indebtedness			$ 100,000,000
FE \| Revolving Credit Facility \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Outstanding borrowings		1,200,000,000
Line of credit facility, remaining borrowing capacity		1,300,000,000
FE \| Line of Credit \| Letter of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Outstanding borrowings			$ 4,000,000
FET Sub-limits \| Revolving Credit Facility \| Line of Credit
Short-Term Borrowings and Bank Lines of Credit (Textuals) [Abstract]
Outstanding borrowings		1,000,000,000
Proceeds from lines of credit		$ 1,000,000,000