COMMITMENTS, GUARANTEES AND CONTINGENCIES - Schedule of Potential Collateral Obligations (Details) $ in Millions	6 Months Ended
	Jun. 30, 2026 USD ($)
Guarantor Obligations [Line Items]
Percent of face amount of debt	100.00%
Curing period	30 days
JCP&L
Guarantor Obligations [Line Items]
Percent of face amount of debt	100.00%
Curing period	30 days
Total Exposure from Contractual Obligations
Guarantor Obligations [Line Items]
Potential Collateral Obligations	$ 315
Total Exposure from Contractual Obligations \| JCP&L
Guarantor Obligations [Line Items]
Potential Collateral Obligations	90
Total Exposure from Contractual Obligations \| FE
Guarantor Obligations [Line Items]
Potential Collateral Obligations	132
Total Exposure from Contractual Obligations \| Electric Companies and Transmission Companies
Guarantor Obligations [Line Items]
Potential Collateral Obligations	183
Upon downgrade
Guarantor Obligations [Line Items]
Potential Collateral Obligations	71
Upon downgrade \| JCP&L
Guarantor Obligations [Line Items]
Potential Collateral Obligations	70
Upon downgrade \| FE
Guarantor Obligations [Line Items]
Potential Collateral Obligations	1
Upon downgrade \| Electric Companies and Transmission Companies
Guarantor Obligations [Line Items]
Potential Collateral Obligations	70
Surety bonds (collateralized amount)
Guarantor Obligations [Line Items]
Potential Collateral Obligations	$ 244
Percent of face amount of debt	60.00%
Capped portion of surety bond obligations	$ 20
Surety bonds (collateralized amount) \| JCP&L
Guarantor Obligations [Line Items]
Potential Collateral Obligations	20
Surety bonds (collateralized amount) \| FE
Guarantor Obligations [Line Items]
Potential Collateral Obligations	131
Surety bonds (collateralized amount) \| Electric Companies and Transmission Companies
Guarantor Obligations [Line Items]
Potential Collateral Obligations	$ 113