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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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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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Amount of increase (decrease) in loss contingency liability.

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COMMITMENTS, GUARANTEES AND CONTINGENCIES - Narrative (Details) $ in Millions			3 Months Ended	6 Months Ended
	Feb. 09, 2022 USD ($)	Jul. 21, 2021 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Feb. 12, 2024 officer
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value			$ 955.0	$ 955.0
Company posted collateral related to net liability positions			135.0	135.0
Collateral received			34.0	34.0
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			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
FE
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value			516.0	516.0
Other Assurances
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value			$ 439.0	$ 439.0