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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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Commitments, Guarantees and Contingencies - Narrative (Details) $ in Millions	Feb. 09, 2022 USD ($)	Jul. 21, 2021 USD ($)	Sep. 30, 2022 USD ($)	Mar. 11, 2022 director	Dec. 31, 2021 USD ($)	Nov. 30, 2021 USD ($)
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated			$ 1,100.0
Company posted collateral related to net liability positions			36.0
Collateral received			$ 321.0
Goal to reduce in GHG emissions			30.00%
Chief Executive Officer \| Code of Conduct Violation, Recoupment Amount
Guarantor Obligations [Line Items]
Proposed penalty amount						$ 56.0
United States v. Householder, et al.
Guarantor Obligations [Line Items]
Number of board members not seeking re-election \| director				6
Number of board members on special committee \| director				3
Smith v FirstEnergy Corp et al., Buldas v FirstEnergy Corp. et al., and Hudock and Cameo Countertops, Inc. v. FirstEnergy Corp. et al.
Guarantor Obligations [Line Items]
Loss contingency accrual					$ 37.5
Emmons v. FirstEnergy Corp. et al.
Guarantor Obligations [Line Items]
Loss contingency accrual					$ 37.5
Shareholder Derivative Lawsuit
Guarantor Obligations [Line Items]
Amount awarded to other party	$ 36.0
Amount awarded from other party	$ 180.0
Regulation of Waste Disposal
Guarantor Obligations [Line Items]
Accrual for environmental loss contingencies			$ 103.0
Environmental liabilities former gas facilities			65.0
FE
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated			591.0
Other Assurances
Guarantor Obligations [Line Items]
Outstanding guarantees and other assurances aggregated			$ 460.0
U.S. Attorney's Office \| United States v. Householder, et al.
Guarantor Obligations [Line Items]
Term of payments		60 days
Term of DPA		3 years
Loss in period		$ 230.0
United States Treasury \| United States v. Householder, et al.
Guarantor Obligations [Line Items]
Amount awarded to other party		115.0
Ohio Development Service \| United States v. Householder, et al.
Guarantor Obligations [Line Items]
Amount awarded to other party		$ 115.0