SEGMENT INFORMATION - Narrative (Details) customer in Millions, $ in Billions	3 Months Ended	12 Months Ended
	Mar. 31, 2025 USD ($) customer site MW	Dec. 31, 2025 site MW	Dec. 31, 2024 site MW
Segment Reporting Information [Line Items]
Number of customers \| customer	6.0
FEV \| Global Holding
Segment Reporting Information [Line Items]
Investment ownership percentage	33.33%
JERSEY CENTRAL POWER & LIGHT COMPANY
Segment Reporting Information [Line Items]
Number of customers \| customer	1.2
Distribution Segment
Segment Reporting Information [Line Items]
Number of customers \| customer	4.3
Distribution Segment \| JERSEY CENTRAL POWER & LIGHT COMPANY
Segment Reporting Information [Line Items]
Number of customers \| customer	1.2
Integrated Segment
Segment Reporting Information [Line Items]
Plant capacity (in MW's)	3,604
Other Business Operations \| FE
Segment Reporting Information [Line Items]
Long-term debt and other long-term obligations \| $	$ 6.5
Other Business Operations \| OVEC
Segment Reporting Information [Line Items]
Plant capacity (in MW's)	67
Integrated \| MP and PE \| Solar Generation Project
Segment Reporting Information [Line Items]
Plant capacity (in MW's)	50
Number of approved solar sites \| site	5
Number of completed solar sites \| site			2
Integrated \| MP and PE \| Solar Generation Project \| Forecast
Segment Reporting Information [Line Items]
Plant capacity (in MW's)		26
Number of sites expected to be completed \| site		3
Integrated \| MP and PE \| Solar Generation Project \| West Virginia
Segment Reporting Information [Line Items]
Plant capacity (in MW's)			24