v3.26.1
PENSION AND OTHER POST-EMPLOYMENT BENEFITS - Narrative (Details) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Employee benefit plan funding and related payments $ 22 $ 24
Pension    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Discount rate 8.00%  
Expected future contributions $ 250  
Pension | JCP&L    
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]    
Expected future contributions $ 0