Repayments Of Long-Term Debt Including Unamortized Premium

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt premium.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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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