Debt Instrument Convertible, Conversion Price, Premium

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- Definition

Debt Instrument, Convertible, Threshold Percentage Of Stock Trading Price

+ References

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- Definition

Debt Instrument, Convertible, Threshold Trading Days, Measurement Period

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- Definition

Fair Value of Financial Instruments.

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- Definition

Investments not required to be disclosed.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

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

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- Definition

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

+ References

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Amount of realized and unrealized gain (loss) on investment.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

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- Definition

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

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- Definition

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 - Narrative (Details) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 16, 2025 USD ($)	Jun. 12, 2025 USD ($) tradingDay consecutiveTradingDay $ / shares	Jun. 30, 2025 USD ($)	Sep. 30, 2025 USD ($) $ / shares	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) $ / shares	Sep. 30, 2024 USD ($)	Sep. 04, 2025 USD ($)	Aug. 13, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 05, 2024 USD ($)
Fair Value of Financial Instruments [Line Items]
Investments not required to be disclosed				$ 342		$ 342				$ 370
Repayments of debt						2,179	$ 1,710
Long-term debt						5,925	1,200
JERSEY CENTRAL POWER & LIGHT COMPANY
Fair Value of Financial Instruments [Line Items]
Repayments of debt						0	500
Long-term debt						$ 1,350	0
Senior Unsecured Convertible Notes \| 3.625%, Convertible Notes Maturity 2029
Fair Value of Financial Instruments [Line Items]
Face amount of debt		$ 1,350
Senior Unsecured Convertible Notes \| 3.875%, Convertible Notes Maturity 2031
Fair Value of Financial Instruments [Line Items]
Face amount of debt		$ 1,150
Senior Unsecured Convertible Notes \| Convertible Notes Maturity 2029
Fair Value of Financial Instruments [Line Items]
Issuance interest rate		3.625%
Senior Unsecured Convertible Notes \| Convertible Notes Maturity 2031
Fair Value of Financial Instruments [Line Items]
Issuance interest rate		3.875%
Senior Unsecured Convertible Notes \| Convertible Notes Maturity 2029 & 2031
Fair Value of Financial Instruments [Line Items]
Proceeds from issuance of debt		$ 2,470
Debt instrument, convertible, conversion ratio		0.0209275
Debt instrument, conversion price (in dollars per share) \| $ / shares		$ 47.78
Debt instrument convertible premium		20.00%
Redemption price, percentage		100.00%
Senior Unsecured Convertible Notes \| Convertible Notes Maturity 2029 & 2031 \| Debt Conversion Terms One
Fair Value of Financial Instruments [Line Items]
Debt instrument, convertible, threshold trading days \| tradingDay		20
Debt instrument, convertible, threshold consecutive trading days \| tradingDay		30
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Senior Unsecured Convertible Notes \| Convertible Notes Maturity 2029 & 2031 \| Debt Conversion Terms Two
Fair Value of Financial Instruments [Line Items]
Debt instrument, convertible, threshold trading days \| consecutiveTradingDay		5
Debt instrument, convertible, threshold consecutive trading days \| consecutiveTradingDay		10
Threshold trading days measurement period \| tradingDay		10
Debt instrument, measurement period percentage		98.00%
Senior Unsecured Convertible Notes \| Convertible Notes 2026
Fair Value of Financial Instruments [Line Items]
Debt instrument, conversion price (in dollars per share) \| $ / shares				$ 46.48		$ 46.48
Repayments of debt			$ 1,200
Unsecured Debt \| 4.75%, $450 Million Notes Maturity 2033
Fair Value of Financial Instruments [Line Items]
Face amount of debt									$ 450
Unsecured Debt \| JERSEY CENTRAL POWER & LIGHT COMPANY \| Senior Notes Maturity 2035
Fair Value of Financial Instruments [Line Items]
Face amount of debt											$ 700
Unsecured Debt \| JERSEY CENTRAL POWER & LIGHT COMPANY \| Unsecured Senior Notes Due 2029
Fair Value of Financial Instruments [Line Items]
Face amount of debt								$ 350
Unsecured Debt \| JERSEY CENTRAL POWER & LIGHT COMPANY \| Unsecured Senior Notes Due 2031
Fair Value of Financial Instruments [Line Items]
Face amount of debt								500
Unsecured Debt \| JERSEY CENTRAL POWER & LIGHT COMPANY \| Unsecured Senior Notes Due 2036
Fair Value of Financial Instruments [Line Items]
Face amount of debt								$ 500
Unsecured Debt \| JERSEY CENTRAL POWER & LIGHT COMPANY \| Unsecured Senior Notes Due 2026 \| Subsequent Event
Fair Value of Financial Instruments [Line Items]
Issuance interest rate	4.30%
Repayments of debt	$ 650
Corporate-Owned Life Insurance
Fair Value of Financial Instruments [Line Items]
Gain on investments				$ 8	$ 10	$ 17	$ 20