v3.26.1
ORGANIZATION AND BASIS OF PRESENTATION - Narrative (Details)
individual in Millions, customer in Millions, $ in Millions
 3 Months Ended 6 Months Ended
Feb. 13, 2026
Feb. 12, 2026
USD ($)
Feb. 26, 2025
USD ($)
transmission_project
Jun. 30, 2026
USD ($)
individual
transmissionCenter
mi
MW
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
customer
transmissionCenter
individual
mi
MW
Jun. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
Feb. 21, 2025
Regulatory Asset [Line Items]                  
Number of customers | customer           6.0      
Number of regional transmission centers | transmissionCenter       2   2      
Liabilities [1]       $ (43,795)   $ (43,795)   $ (41,978)  
Capitalized cost of equity       30 $ 24 65 $ 46    
Capitalized interest       22 18 41 34    
Variable Interest Entity, Primary Beneficiary                  
Regulatory Asset [Line Items]                  
Liabilities       $ (10,333)   $ (10,333)   (9,933)  
Variable Interest Entity, Primary Beneficiary | Adjustment                  
Regulatory Asset [Line Items]                  
Liabilities               243  
FET | Grid Growth                  
Regulatory Asset [Line Items]                  
Ownership interest 50.00%                
Grid Growth | Grid Growth EHV Holdings, LLC                  
Regulatory Asset [Line Items]                  
Ownership interest 80.00%                
Transource | Grid Growth                  
Regulatory Asset [Line Items]                  
Ownership interest 50.00%                
JCP&L                  
Regulatory Asset [Line Items]                  
Number of customers | customer           1.2      
Transmission services available area populations | individual       2.8   2.8      
Liabilities       $ (6,666)   $ (6,666)   (5,949)  
Capitalized cost of equity       7 7 13 13    
Capitalized interest       $ 6 $ 3 $ 12 $ 6    
Valley Link | PJM 2024 RTEP Window 1 | PJM                  
Regulatory Asset [Line Items]                  
Number of transmission projects | transmission_project     2            
Transmission solutions to the reliability issues     $ 3,000            
Valley Link | FET                  
Regulatory Asset [Line Items]                  
Equity method investment, ownership percentage                 34.00%
Valley Link | FET | PJM 2024 RTEP Window 1 | PJM                  
Regulatory Asset [Line Items]                  
Transmission solutions to the reliability issues     $ 1,000            
Valley Link | Transource                  
Regulatory Asset [Line Items]                  
Equity method investment, ownership percentage                 36.00%
Valley Link | Dominion HV                  
Regulatory Asset [Line Items]                  
Equity method investment, ownership percentage                 30.00%
Grid Growth | PJM 2025 RTEP Window 1 | PJM                  
Regulatory Asset [Line Items]                  
Transmission solutions to the reliability issues   $ 1,000              
Grid Growth | FET | PJM 2025 RTEP Window 1 | PJM                  
Regulatory Asset [Line Items]                  
Transmission solutions to the reliability issues   $ 448              
FET | Brookfield | North American Transmission Company II LLC                  
Regulatory Asset [Line Items]                  
Equity method investment, ownership percentage       49.90%   49.90%      
Other Sundry Investments                  
Regulatory Asset [Line Items]                  
Equity method investments       $ 19   $ 19   38  
Other Sundry Investments | JCP&L                  
Regulatory Asset [Line Items]                  
Equity method investments       $ 0   $ 0   $ 0  
Path Wv | Variable Interest Entity, Not Primary Beneficiary                  
Regulatory Asset [Line Items]                  
Variable interest entities percentage of high voltage transmission line project owned by variable interest entity one in joint venture party two       50.00%   50.00%      
Path Wv | FET | Variable Interest Entity, Not Primary Beneficiary                  
Regulatory Asset [Line Items]                  
Proceeds from divestiture of interest in joint venture       $ 21          
Regulated Transmission                  
Regulatory Asset [Line Items]                  
Service area | mi       24,000   24,000      
Integrated Segment                  
Regulatory Asset [Line Items]                  
Number of customers | customer           2.0      
Plant capacity (in MW's) | MW       3,610   3,610      
[1] As of June 30, 2026, and December 31, 2025, the combined assets of the VIEs were $13,796 million and $13,270 million, respectively, that can only be used to settle obligations of the VIEs. As of June 30, 2026, and December 31, 2025, respectively, these assets include: Cash and cash equivalents of $10 million and $8 million, Restricted cash of $41 million and $40 million, Accounts receivable of $92 million and $92 million, Materials and supplies, at average cost of $1 million and $1 million, Prepaid taxes and other current assets of $20 million and $41 million, Property, plant, and equipment of $13,081 million and $12,475 million, Goodwill of $224 million and $224 million, Investments of $2
million and $19 million, Regulatory assets of $141 million and $22 million, and Other noncurrent assets of $184 million and $348 million. The consolidated liabilities as of June 30, 2026, and December 31, 2025, include $10,333 million and $9,933 million, respectively, of liabilities of VIEs whose creditors have no recourse to FE. As of June 30, 2026, and December 31, 2025, respectively, these liabilities include: Currently payable long-term debt of $52 million and $126 million, Short-term borrowings of $275 million and $245 million, Accrued interest of $112 million and $108 million, Accrued taxes of $327 million and $335 million, Other current liabilities of $6 million and $9 million, Long-term debt and other long-term obligations of $7,291 million and $6,893 million, Accumulated deferred income taxes of $1,623 million and $1,540 million, Regulatory liabilities of $478 million and $346 million, and Other noncurrent liabilities of $169 million and $331 million.