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Public Utilities, Amount Awarded From Other Party

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Public Utilities, Amount Of Treatment Of Corporate Support Costs

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Public Utilities, Approved Demand Reduction Targets

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Public Utilities, Approved Energy Consumption Reduction Targets

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Public Utilities, Approved Energy Consumption Reduction Targets, Cost Recovery

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Public Utilities Estimated Initial Investment

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- Definition

Public Utilities, General Rate Case Authorizations, Revenue, Requested Rate Increase (Decrease), Amount

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Public Utilities, Number of Approved Solar Sites

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Public Utilities, Number of Overall Solar Sites

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Public Utilities, Number Of Unresolved Audit Matters Referred To Other Offices

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Public Utilities, Plant Construction, Capacity of Plants

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Public Utilities, Plant Construction, Percent of Subscriptions Required Prior To Commencement

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- Definition

Public Utilities Reclassification To Operating Expense

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Public Utilities, Recovery Of Project Abandonment, Costs Incurred Thereafter, Percentage

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Public Utilities, Recovery Of Project Abandonment, Prior To Effective Date Costs, Percentage

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Public Utilities, Requested Increase Of Total Revenues, Percentage

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Public Utilities, Requested Program Phase Approval, Proposed Investment Amount

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Public Utilities, Transmission Solutions To The Reliability Issues, Amount

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Regulatory matters.

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Utilities, Basis Point Adder Associated With RTO Membership

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Utilities, Transmission Owning Utilities Join An RTO

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Percentage of public utility's requested debt to capital, including debt and equity.

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Percentage of public utility's requested equity to capital, including debt and equity.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested return on equity.

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REGULATORY MATTERS - Pennsylvania and West Virginia (Details) $ in Millions												9 Months Ended	12 Months Ended
	Oct. 01, 2025 USD ($) MW	Aug. 29, 2025 USD ($)	Jul. 11, 2025	Mar. 14, 2025	Feb. 26, 2025 USD ($)	Jan. 17, 2025	Jul. 22, 2024 USD ($)	Dec. 08, 2023 auditMatter	Apr. 24, 2023 site MW	May 01, 2022 MW	Feb. 24, 2022	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2022 USD ($)
Transmission Related Vegetation Management Programs \| FERC \| FE
Regulatory Matters [Line Items]
Utilities reclassification to operating expense														$ 105.0
Amount of treatment of corporate support costs												$ 97.0
Public utilities, number of unresolved audit matters \| auditMatter								2
Utilities, transmission owning utilities join an RTO											0.00500000
Transmission Related Vegetation Management Programs \| FERC \| JERSEY CENTRAL POWER & LIGHT COMPANY \| FE
Regulatory Matters [Line Items]
Utilities reclassification to operating expense														$ 13.0
Transmission ROE Incentive \| FERC
Regulatory Matters [Line Items]
Utilities, transmission owing utilities join an RTO						0.00500000
Public utilities, amount awarded from other party													$ 46.0
Transmission ROE Incentive \| FERC \| Miscellaneous Income
Regulatory Matters [Line Items]
Public utilities, amount awarded from other party													4.0
Transmission ROE Incentive \| FERC \| Transmission \| Transmission Revenues
Regulatory Matters [Line Items]
Public utilities, amount awarded from other party													$ 42.0
PJM 2024 RTEP Window 1 \| Valley Link Transmission Rate
Regulatory Matters [Line Items]
Transmission solutions to the reliability issues					$ 3,000.0
Capital structure, percentage				40.00%
Equity ratio, percentage				60.00%
Transmission rate, base ROE				10.90%
Recovery of project abandonment costs (percent)			50.00%
Recovery of project abandonment costs incurred thereafter (percent)			100.00%
Pennsylvania \| EE&C Phase IV \| PPUC
Regulatory Matters [Line Items]
Public utilities, approved energy consumption reduction targets, cost recovery												$ 390.0
Pennsylvania \| EE&C Phase IV \| PPUC \| ME
Regulatory Matters [Line Items]
Demand reduction targets												2.90%
Energy consumption reduction targets												3.10%
Pennsylvania \| EE&C Phase IV \| PPUC \| PN
Regulatory Matters [Line Items]
Demand reduction targets												3.30%
Energy consumption reduction targets												3.00%
Pennsylvania \| EE&C Phase IV \| PPUC \| Penn
Regulatory Matters [Line Items]
Demand reduction targets												2.00%
Energy consumption reduction targets												2.70%
Pennsylvania \| EE&C Phase IV \| PPUC \| WP
Regulatory Matters [Line Items]
Demand reduction targets												2.50%
Energy consumption reduction targets												2.40%
Pennsylvania \| New LTIIPs \| PPUC \| Pennsylvania Companies
Regulatory Matters [Line Items]
Proposed investment amount							$ 1,600.0
Pennsylvania \| 2025-2029 LTIIP \| PPUC \| Pennsylvania Companies
Regulatory Matters [Line Items]
Proposed investment amount							$ 1,400.0
West Virginia \| WVPSC \| MP and PE
Regulatory Matters [Line Items]
Utilities requested rate increase amount		$ 14.0
Public utilities, increase of total revenues, percentage		0.80%
West Virginia \| WVPSC \| MP and PE \| Solar Generation Project
Regulatory Matters [Line Items]
Percent of subscriptions required prior to commencement of construction										85.00%
Plant capacity (in MW's) \| MW									30	50
Number of approved solar sites \| site									3
Utilities number of overall solar sites \| site									5
Amount of requested increase (decrease)		$ (3.2)
West Virginia \| WVPSC \| MP and PE \| Solar Generation Project \| Subsequent Event
Regulatory Matters [Line Items]
Public utilities, near-term market capacity purchases (in MV's) \| MW	70
West Virginia \| WVPSC \| MP and PE \| Natural Gas Generation Project \| Subsequent Event
Regulatory Matters [Line Items]
Public utilities, near-term market capacity purchases (in MV's) \| MW	1,200
Estimated initial investment	$ 2,500.0