Asset Retirement Obligation, Agreed Funding Period

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- Definition

Asset Retirement Obligation, Discount Rate

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- Definition

Asset Retirement Obligation, Escrow Deposit

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- Definition

Cash Collateral Received For Supply Contracts, Net

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- Definition

Company Posted Collateral Related To Net Liability Positions.

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- Definition

Environmental Liabilities Former Gas Facilities.

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- Definition

Loss Contingency, Settlement Agreement, Term

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- Definition

Loss Contingency, Settlement Agreement, Term of Payments

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- Definition

Loss Contingency, Settlement Agreement, Will Not Be Recovered In Rates Or Charged to Customers

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No definition available.

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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- Definition

Amount of asset retirement obligations incurred during the period.

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- Definition

Amount of increase (decrease) in asset retirement obligations.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

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No definition available.

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- Definition

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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COMMITMENTS, GUARANTEES AND CONTINGENCIES - Narrative (Details) - USD ($) $ in Millions				9 Months Ended	12 Months Ended
	Mar. 04, 2025	Feb. 03, 2025	Jul. 21, 2021	Sep. 30, 2025	Dec. 31, 2024
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value				$ 1,100
Company posted collateral related to net liability positions				185
Collateral received				32
Liabilities incurred				1	$ 95
JERSEY CENTRAL POWER & LIGHT COMPANY
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value				46
Company posted collateral related to net liability positions				28
Collateral received				7
Liabilities incurred				0	0
United States v. Householder, et al. \| U.S. Attorney's Office
Guarantor Obligations [Line Items]
Term of DPA			3 years
Loss in period			$ 230
Term of payments			60 days
United States v. Householder, et al. \| United States Treasury
Guarantor Obligations [Line Items]
Amount of refunds announced			$ 115
United States v. Householder, et al. \| Ohio Development Service
Guarantor Obligations [Line Items]
Amount of refunds announced			115
Amount that won't be recovered in rates or charged to customers			$ 230
Regulation of Waste Disposal
Guarantor Obligations [Line Items]
Changes in timing and amount of estimated cash flows					139
Accrual for environmental loss contingencies				93
Environmental liabilities former gas facilities				67
Regulation of Waste Disposal \| JERSEY CENTRAL POWER & LIGHT COMPANY
Guarantor Obligations [Line Items]
Changes in timing and amount of estimated cash flows					0
Regulation of Waste Disposal \| Corporate Non Segment
Guarantor Obligations [Line Items]
Liabilities incurred	$ 130				87
Environmental Liability
Guarantor Obligations [Line Items]
Asset retirement obligation, escrow deposit	$ 130	$ 160		$ 46	$ 160
Agreed funding period	5 years	5 years			5 years
Asset retirement obligation, discount rate	4.80%