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v3.25.3

FAIR VALUE MEASUREMENTS - Schedule of Long-term Debt Redemption and Issuance (Details) - USD ($) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Aug. 31, 2025 | Jun. 30, 2025 | May 31, 2025 | Apr. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2025 | Sep. 30, 2024
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Repayments of debt |  |  |  |  |  |  | $ 2,179 | $ 1,710
Debt issuances |  |  |  |  |  |  | 5,925 | 1,200
JCP&L |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Repayments of debt |  |  |  |  |  |  | 0 | 500
Debt issuances |  |  |  |  |  |  | $ 1,350 | $ 0
2.05% Unsecured Senior Notes Maturity 2025 | Senior Unsecured Notes | FE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  |  |  |  | 2.05% |  |
Repayments of debt |  |  |  |  |  | $ 300 |  |
3.76% Unsecured Senior Notes Maturing 2025 | Senior Unsecured Notes | TrAIL |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  |  | 3.76% |  |  |  |
Repayments of debt |  |  |  | $ 75 |  |  |  |
3.85% Unsecured Senior Notes Maturing 2025 | Senior Unsecured Notes | TrAIL |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 3.85% |  |  |  |  |
Repayments of debt |  |  | $ 550 |  |  |  |  |
4.00% Unsecured Senior Notes Maturing 2026 | Senior Unsecured Convertible Notes | FE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 4.00% |  |  |  |  |
Repayments of debt |  |  | $ 1,206 |  |  |  |  |
Repayments of long-term debt including premium |  |  | 1,225 |  |  |  |  |
Make-whole premium |  |  | $ 19 |  |  |  |  |
5.00%, $600 Million Notes Maturity 2031 | Senior Unsecured Notes | TrAIL |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  |  |  | 5.00% |  |  |
Debt issuances |  |  |  |  | $ 600 |  |  |
5.00% Unsecured Senior Notes Maturing 2030 | Senior Unsecured Notes | ATSI |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  |  | 5.00% |  |  |  |
Debt issuances |  |  |  | $ 225 |  |  |  |
4.95% Unsecured Senior Notes Maturing 2029 | Senior Unsecured Notes | OE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  |  | 4.95% |  |  |  |
Debt issuances |  |  |  | $ 300 |  |  |  |
5.00% Secured Senior Notes Maturing 2031 | Senior Unsecured Notes | MAIT |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 5.00% |  |  |  |  |
Debt issuances |  |  | $ 200 |  |  |  |  |
5.00%, 200 Million Notes Maturing 2030 | FMBs | PE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 5.00% |  |  |  |  |
Debt issuances |  |  | $ 200 |  |  |  |  |
5.18%, $100 Million Notes Maturity 2030 | Senior Secured Notes | TE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 5.18% |  |  |  |  |
Debt issuances |  |  | $ 100 |  |  |  |  |
3.63%, $1,350 Million Notes Maturity 2029 | Senior Unsecured Convertible Notes | FE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 3.63% |  |  |  |  |
Debt issuances |  |  | $ 1,350 |  |  |  |  |
3.88%, $1,150 Million Notes Maturity 2031 | Senior Unsecured Convertible Notes | FE |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  |  | 3.88% |  |  |  |  |
Debt issuances |  |  | $ 1,150 |  |  |  |  |
4.75%, $450 Million Notes Maturity 2033 | Senior Unsecured Notes | FET |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate |  | 4.75% |  |  |  |  |  |
Debt issuances |  | $ 450 |  |  |  |  |  |
4.15%, $350 Million Notes Maturity 2029 | Senior Unsecured Notes | JCP&L |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate | 4.15% |  |  |  |  |  | 4.15% |
Debt issuances | $ 350 |  |  |  |  |  |  |
4.40%, $500 Million Notes Maturity 2031 | Senior Unsecured Notes | JCP&L |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate | 4.40% |  |  |  |  |  | 4.40% |
Debt issuances | $ 500 |  |  |  |  |  |  |
5.15%, $500 Million Notes Maturity 2036 | Senior Unsecured Notes | JCP&L |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate | 5.15% |  |  |  |  |  | 5.15% |
Debt issuances | $ 500 |  |  |  |  |  |  |
4.30%, 650 Million Senior Notes Due 2026 | Senior Unsecured Notes | JCP&L | Revolving Credit Facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Issuance interest rate | 4.30% |  |  |  |  |  | 4.30% |
Face amount of debt | $ 650 |  |  |  |  |  | $ 650 |

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