COMMITMENTS, GUARANTEES AND CONTINGENCIES - Schedule of Potential Collateral Obligations (Details) $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)
Guarantor Obligations [Line Items]
Guarantor obligations	$ 243
Percent of face amount of debt	100.00%
Curing period	30 days
FE
Guarantor Obligations [Line Items]
Guarantor obligations	$ 80
Electric Companies and Transmission Companies
Guarantor Obligations [Line Items]
Guarantor obligations	163
Upon downgrade
Guarantor Obligations [Line Items]
Guarantor obligations	67
Upon downgrade | FE
Guarantor Obligations [Line Items]
Guarantor obligations	1
Upon downgrade | Electric Companies and Transmission Companies
Guarantor Obligations [Line Items]
Guarantor obligations	66
Surety Bond (Collateralized Amount)
Guarantor Obligations [Line Items]
Guarantor obligations	$ 176
Percent of face amount of debt	60.00%
Capped portion of surety bond obligations	$ 38
Surety Bond (Collateralized Amount) | FE
Guarantor Obligations [Line Items]
Guarantor obligations	79
Surety Bond (Collateralized Amount) | Electric Companies and Transmission Companies
Guarantor Obligations [Line Items]
Guarantor obligations	$ 97