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

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Amount of asset retirement obligations incurred during the period.

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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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Amount of increase (decrease) in loss contingency liability.

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COMMITMENTS, GUARANTEES AND CONTINGENCIES - Narrative (Details) $ in Millions			3 Months Ended		9 Months Ended
	Feb. 09, 2022 USD ($)	Jul. 21, 2021 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Sep. 30, 2024 USD ($)	Feb. 12, 2024 officer
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value			$ 978.0		$ 978.0
Company posted collateral related to net liability positions			160.0		160.0
Collateral received			35.0		35.0
Liabilities incurred					95.0
United States v. Householder, et al.
Guarantor Obligations [Line Items]
Number of senior officers \| officer						2
United States v. Householder, et al. \| U.S. Attorney's Office
Guarantor Obligations [Line Items]
Term of DPA		3 years
Loss in period		$ 230.0
Term of payments		60 days
United States v. Householder, et al. \| United States Treasury
Guarantor Obligations [Line Items]
Amount of refunds announced		$ 115.0
United States v. Householder, et al. Related SEC Investigation
Guarantor Obligations [Line Items]
Other operating expenses				$ 100.0
United States v. Householder, et al. Related OOCIC Investigation
Guarantor Obligations [Line Items]
Other operating expenses				19.5
Shareholder Derivative Lawsuit
Guarantor Obligations [Line Items]
Amount of refunds announced	$ 36.0
Amount awarded from other party	180.0
Net return on deposited funds	$ 7.0
Regulation of Waste Disposal
Guarantor Obligations [Line Items]
Changes in timing and amount of estimated cash flows			25.0	125.0
Accrual for environmental loss contingencies			96.0		96.0
Environmental liabilities former gas facilities			69.0		69.0
Regulation of Waste Disposal \| Corporate Non Segment
Guarantor Obligations [Line Items]
Liabilities incurred				$ 87.0
Changes in timing and amount of estimated cash flows			25.0
FE
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value			517.0		517.0
Other Assurances
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value			$ 461.0		$ 461.0