HB 6 House Bill 6 [Member] House Bill 6 Receivable Type [Axis] Receivable Type [Axis] Yard's Creek Energy Yard's Creek Energy, LLC Hydro Generation Facility [Member] Yard's Creek Energy, LLC Hydro Generation Facility [Member] Miscellaneous income, net Miscellaneous income (expense), net Other Nonoperating Income (Expense) U.S. state debt securities US States and Political Subdivisions Debt Securities [Member] Segment Financial Information Segment Financial Information Abstract Segment Financial Information. Gain (loss) on Disposal of FES and FENOC, before tax Deconsolidation, Gain (Loss), Amount, Before Tax Deconsolidation, Gain (Loss), Amount, Before Tax Business Units [Domain] Business Units [Domain] Business Units. Settlements, Derivative Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements COMMITMENTS, GUARANTEES AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Related Party [Axis] Related Party [Axis] Interest expense Interest expense Interest and Debt Expense Interest and dividend income Investment Income From Trusts Investment Income From Trusts Fair Value Inputs, Assets and Liabilities, Quantitative Information [Table] Fair Value Inputs, Assets and Liabilities, Quantitative Information [Table] Fair Value Inputs, Assets and Liabilities, Quantitative Information [Table] Business Segments [Axis] Segments [Axis] PENSIONS AND OTHER POST-EMPLOYMENT BENEFITS Retirement Benefits [Text Block] Schedule of Accumulated Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] Long-term debt Other Contract [Member] Business Units [Axis] Business Units [Axis] Business units. Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Statistical Measurement [Domain] Statistical Measurement [Domain] Line of Credit Line of Credit [Member] Accumulated deferred income taxes Deferred Income Tax Liabilities, Net Receivables- Receivables, Net, Current [Abstract] Current Fiscal Year End Date Current Fiscal Year End Date Approved amount of annual increase (decrease) Approved amount of annual increase Public Utilities, Approved Rate Increase (Decrease), Amount Amount of revenue increase Public Utilities, Settled Revenue Increase, Amount Public Utilities, Settled Revenue Increase, Amount Capitalized financing costs Interest Costs Capitalized Adjustment Receivables Increase (Decrease) in Accounts and Other Receivables Long-term debt Debt issuances Proceeds from Issuance of Long-term Debt OPERATING INCOME Operating Income (Loss) Entity Address, Postal Zip Code Entity Address, Postal Zip Code Total current liabilities Liabilities, Current External Customers External Customers [Member] External Customers [Member] Reclassifications from AOCI Reclassification out of Accumulated Other Comprehensive Income [Member] Number of additional executives terminated Number of Additional Executives Terminated Number of Additional Executives Terminated Regulatory Matters [Line Items] Regulatory Matters [Line Items] Regulatory matters. Net accelerated credits Defined Benefit Plan, Accelerated Amortization of Prior Service Cost (Credit) Defined Benefit Plan, Accelerated Amortization of Prior Service Cost (Credit) COMMITMENTS, GUARANTEES AND CONTINGENCIES (Note 10) Commitments and Contingencies ASSETS Assets [Abstract] Investment, Name [Axis] Investment, Name [Axis] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Entity Shell Company Entity Shell Company General taxes Utilities Operating Expense, Taxes Cover [Abstract] Cover [Abstract] Accounts payable Accounts Payable, Current Other comprehensive loss Other Comprehensive Income (Loss), before Tax Document Type Document Type Regulatory Matters, Secondary [Domain] Regulatory Matters, Secondary [Domain] Regulatory Matters, Secondary [Domain] Income available to common stockholders, per common share: Earnings Per Share Reconciliation [Abstract] ACCUMULATED OTHER COMPREHENSIVE INCOME Comprehensive Income (Loss) Note [Text Block] Number of existing utility operating companies Number Of Existing Utility Operating Companies Number of existing utility operating companies. Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Accumulated deficit Retained Earnings (Accumulated Deficit) Purchase price Asset Acquisition, Consideration Transferred Asset Acquisition, Consideration Transferred Fair Value of Financial Instruments [Table] Fair Value of Financial Instruments [Table] Fair Value Of Financial Instruments. Reconciliation of Changes in the Fair Value Roll Forward of Level 3 Measurements of NUG Contracts Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Pennsylvania PENNSYLVANIA Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Purchases, Net Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset And Liability Purchases Fair value measurement with unobservable inputs reconciliation recurring basis asset and liability purchases total. Long-term debt and other long-term obligations Long-term Debt and Lease Obligation INCOME ALLOCATED TO PREFERRED STOCKHOLDERS (Note 4) Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Unrealized gain (loss), Derivative Assets Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset unrealized gain loss Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset unrealized gain loss Customer [Axis] Customer [Axis] WP West Penn Power Company [Member] West Penn Power Company Guarantor obligations Guarantor Obligations, Maximum Exposure, Undiscounted Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Excise taxes collected Excise Taxes Collected Diluted - Continuing Operations (in dollars per share) Income from continuing operations, diluted (in dollars per share) Income (Loss) from Continuing Operations, Per Diluted Share Income allocated to preferred shareholders, preferred dilutive Dilutive Securities, Effect on Basic Earnings Per Share Regulatory liabilities Regulatory Liability, Noncurrent Diluted - Discontinued Operations (in dollars per share) Discontinued operations, diluted (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share Document Quarterly Report Document Quarterly Report Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Penn Pennsylvania Power Company [Member] Pennsylvania Power Company Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Other Electric Worldwide Unregulated Revenue [Member] Electric Worldwide Unregulated Revenue [Member] Other Other Liabilities, Noncurrent Other Payments for (Proceeds from) Other Investing Activities Stock Investment Plan and certain share-based benefit plans Stock Issued During Period, Value, Employee Benefit Plan Planned capital expenditures Public Utilities, Approved Planned Capital Expenditures Public Utilities, Approved Planned Capital Expenditures Liability Class [Axis] Liability Class [Axis] Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Accelerated net pension and OPEB prior service credits Deconsolidation, Acceleration of Prior Service Credits Deconsolidation, Acceleration of Prior Service Credits JCP&L Jcp And L [Member] Jersey Central Power & Light Company. Reconciling Adjustments Segment Reconciling Items [Member] Other Non-Customer Revenue Other Non-Customer Revenue [Member] Other Non-Customer Revenue [Member] Construction work in progress Construction in Progress, Gross Materials and supplies, at average cost Inventory, Net Total revenues from contracts with customers Revenue from Contract with Customer, Excluding Assessed Tax JCP&L, ME and PN Jersey Central Power and Light Company, Metropolitan Edison Company, Pennsylvania Power Company and GPU Nuclear, Inc. [Member] Jersey Central Power and Light Company, Metropolitan Edison Company, Pennsylvania Power Company and GPU Nuclear, Inc. [Member] Incremental energy savings goal thereafter (percent) Incremental Energy Savings Goal, Percent Incremental Energy Savings Goal, Percent Measurement Frequency [Domain] Measurement Frequency [Domain] Investments Investment, Policy [Policy Text Block] INCOME FROM CONTINUING OPERATIONS Income from continuing operations Income (loss) from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Purchases, Derivative Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases West Virginia WEST VIRGINIA New financing- New Financing [Abstract] New Financing Abstract. Entity File Number Entity File Number Geographical [Domain] Geographical [Domain] Transmission Transmission Services [Member] Transmission Services [Member] Investment ownership percentage Investment, Ownership Percentage Pledged as Collateral Investment, Ownership Percentage Pledged as Collateral Statement [Line Items] Statement [Line Items] Class of Stock [Domain] Class of Stock [Domain] Customer Customer [Member] Customer. Meter deployment period Public Utilities, Meter Deployment Period Public Utilities, Meter Deployment Period Settlement of certain claims Debtor Reorganization Items, Discharge of Claims and Liabilities Debt term Debt Instrument, Term Target Period [Domain] Target Period [Domain] Target period. Other Other Securities [Member] Other Securities. Document Fiscal Period Focus Document Fiscal Period Focus Redemptions and repayments- Redemptions And Repayments [Abstract] Redemptions And Repayments Abstract. Accrued interest Interest Payable, Current Statement [Table] Statement [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Write-offs Accounts Receivable, Allowance for Credit Loss, Writeoff Statistical Measurement [Axis] Statistical Measurement [Axis] Interest costs Defined Benefit Plan, Interest Cost Distribution services Distribution Services [Member] Distribution Services [Member] Amount of refundable AMT credits Effective Income Tax Rate Reconciliation, CARES Act, Refundable AMT Credits, Amount Effective Income Tax Rate Reconciliation, CARES Act, Refundable AMT Credits, Amount Credit Facility [Axis] Credit Facility [Axis] Model Model [Member] Model [Member] Deferred income taxes and investment tax credits, net Deferred Income Taxes and Tax Credits EE&C Phase III Energy Efficiency and Conservation [Member] Energy Efficiency and Conservation [Member] One-time termination benefit Defined Benefit Plan, Benefit Obligation, One-Time Termination Benefit Defined Benefit Plan, Benefit Obligation, One-Time Termination Benefit Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract] Weighted Average Weighted Average [Member] Income (loss) from discontinued operations available to common stockholders Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic Other Assurances Other Assurances [Member] Other Assurances [Member] Total capitalization Capitalization, Long-term Debt and Equity Consolidation Policy Consolidation, Policy [Policy Text Block] Enhanced service reliability program term Public Utilities, Enhanced Service Reliability Program Term Public Utilities, Enhanced Service Reliability Program Term Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Revenues Disposal Group, Including Discontinued Operation, Revenue Reconciliation of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Guarantee Type [Axis] Guaranteed Insurance Contract, Type of Guarantee [Axis] WEIGHTED AVERAGE NUMBER OF COMMON SHARES OUTSTANDING: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Beginning Balance, Derivative Liabilities Ending Balance, Derivative Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Temporary increase in rate cap Public Utilities, Interim Rate Increase (Decrease), Percentage Recovery period Public Utilities, Cost Recovery Period Public Utilities, Cost Recovery Period Corporate/Other Corporate, Non-Segment [Member] Amendment Flag Amendment Flag Pleasants Power Station Pleasants Power Station [Member] Pleasants Power Station [Member] Net cash provided from operating activities Net Cash Provided by (Used in) Operating Activities Realized gains Debt and Equity Securities, Realized Gains Debt and Equity Securities, Realized Gains Related Party [Domain] Related Party [Domain] Measurement Frequency [Axis] Measurement Frequency [Axis] Expenditures for cost recovery program Expenditures For Cost Recovery Program Expenditures for cost recovery program. Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Noncurrent liabilities - held for sale (Note 10) Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent Annual revenue cap for rider Public Utilities, Annual Revenue Cap for Rider Public Utilities, Annual Revenue Cap for Rider Gains & Losses on Cash Flow Hedges Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Number of agreements Debt Instrument, Number of Agreements Debt Instrument, Number of Agreements Derivative Instrument Risk [Axis] Derivative Instrument [Axis] Commercial Commercial Customers [Member] Commercial Customers [Member] Stock Investment Plan and certain share-based benefit plans (in shares) Stock Issued During Period, Shares, Employee Benefit Plan Financial Instruments [Domain] Financial Instruments [Domain] Surety Bond (Collateralized Amount) Surety Bond [Member] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Fair Value Measurement [Domain] Fair Value Measurement [Domain] Geographical [Axis] Geographical [Axis] Change in amount of valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Local Phone Number Local Phone Number Segments [Domain] Segments [Domain] MP and PE Monogahela Power Company and The Potomac Edison Company [Member] Monogahela Power Company and The Potomac Edison Company [Member] Number of customers served by utility operating companies Number Of Customers Number Of Customers. Incremental energy savings goal per year (percent) Incremental Energy Savings Goal, Thereafter, Percent Incremental Energy Savings Goal, Thereafter, Percent Cost Basis Debt Securities, Available-for-sale, Amortized Cost Regulated Distribution Regulated Distribution Regulated Distribution [Member] Regulated Distribution. Schedule of Accumulated Other Comprehensive Income [Table] Schedule of Accumulated Other Comprehensive Income [Table] Schedule of Accumulated Other Comprehensive Income [Table] Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Term of energy contract Energy Contract, Term Energy Contract, Term PUCO Public Utilities Commission Of Ohio [Member] Public Utilities Commission Of Ohio [Member] Capitalized interest Interest Costs Capitalized Less — Allowance for uncollectible customer receivables Allowance for uncollectible accounts Accounts Receivable, Allowance for Credit Loss, Current Advanced Metering Infrastructure Advanced Metering Infrastructure [Member] Advanced Metering Infrastructure Decrease in regulatory liability Public Utilities, Settled Decrease In Regulatory Liability Public Utilities, Settled Decrease In Regulatory Liability IT Access Agreement IT Access Agreement [Member] IT Access Agreement [Member] State and Local Jurisdiction State and Local Jurisdiction [Member] Pension and OPEB prior service costs Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Other operating expenses Disposal Group, Including Discontinued Operation, Other Operating Expenses Disposal Group, Including Discontinued Operation, Other Operating Expenses Other Other Services [Member] Other Services [Member] Assumed conversion of preferred stock (in shares) Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock Derivative Revenue Derivative Revenue [Member] Derivative Revenue [Member] Entity Current Reporting Status Entity Current Reporting Status Term Loan Facility due November 2024 Term Loan Facility due November 2024 [Member] Term Loan Facility due November 2024 Other Other Assets, Noncurrent Percent of federal poverty income level Public Utilities, Regulatory Asset, Compliance Expenses, Percent of Federal Poverty Income Level Public Utilities, Regulatory Asset, Compliance Expenses, Percent of Federal Poverty Income Level SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Short-term cash investments Cash and Cash Equivalents, Fair Value Disclosure Total assets Total assets Assets Reclassification Out of Accumulated Other Comprehensive Income [Line Items] Reclassification out of Accumulated Other Comprehensive Income [Line Items] [Line Items] for Reclassification out of Accumulated Other Comprehensive Income [Table] Worthless stock deduction, net of tax Disposal Group, Including Discontinued Operation, Worthless Stock Deduction, Net of Tax Disposal Group, Including Discontinued Operation, Worthless Stock Deduction, Net of Tax Increase in depreciation rate Public Utilities, Requested Rate Increase, Increase in Depreciation Rate Public Utilities, Requested Rate Increase, Increase in Depreciation Rate Upon Further Downgrade Upon Further Downgrade [Member] Upon Further Downgrade [Member] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Loss from discontinued operations, before tax Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax Public Utilities, Regulatory Proceeding [Axis] Public Utilities, Regulatory Proceeding [Axis] PN Pennsylvania Electric Company [Member] Pennsylvania Electric Company ARP Alternative Revenue Program [Member] Alternative Revenue Program [Member] Senior Secured Term Loan Senior Secured Term Loan [Member] Senior Secured Term Loan [Member] Amortization of prior service costs (credits) Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Loss Contingencies By Claims [Domain] Loss Contingencies By Claims [Domain] Loss Contingencies By Claims. CSAPR CSAPR [Member] CSAPR [Member] Accrued taxes Accrued Income Taxes, Current Subsequent Event Type [Axis] Subsequent Event Type [Axis] Three Month Period Three Month Period [Member] Three Month Period [Member] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Global Holding Global Holding [Member] Global Holding [Member] Entity Small Business Entity Small Business Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Interest expense Interest Expense ENEC Expanded Net Energy Cost [Member] Expanded Net Energy Cost [Member] Depreciation and amortization Depreciation, Depletion and Amortization Entity Filer Category Entity Filer Category Worthless stock deduction Disposal Group, Including Discontinued Operation, Worthless Stock Deduction Disposal Group, Including Discontinued Operation, Worthless Stock Deduction Product and Service [Axis] Product and Service [Axis] Entity Address, City or Town Entity Address, City or Town Net prior service costs Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] Energy Efficiency and Peak Demand Reduction Energy Efficiency and Peak Demand Reduction [Member] Energy Efficiency and Peak Demand Reduction Loss contingency, damages sought Loss Contingency, Damages Sought, Value Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Schedule of customer disconnections and collection activities Schedule of Customer Disconnections and Collection Activities [Table Text Block] Schedule of Customer Disconnections and Collection Activities Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS Net Income (Loss) Available to Common Stockholders, Basic Level 1 Fair Value, Inputs, Level 1 [Member] Regulated Operations [Abstract] Regulated Operations [Abstract] Materials and supplies Increase (Decrease) in Inventories Proceeds from the Sale of Investments in Available-for-sale Securities, Realized Gains and Losses on Those Sales, and Interest and Dividend Income Proceeds From Sale Of Investments In Available For Sale Securities Realized Gains And Losses On Those Sales And Interest And Dividend Income [Table Text Block] Proceeds from sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income. Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Document Fiscal Year Focus Document Fiscal Year Focus Regulatory Agency [Axis] Regulatory Agency [Axis] TMI-2 Three Mile Island Unit 2 [Member] Three Mile Island Unit 2 [Member] Debt Instrument [Axis] Debt Instrument [Axis] OPIC Additional Paid-in Capital [Member] Revised requested rate increase Public Utilities, Requested Rate Increase, Revised Increase Due Effects of 2017 Tax Cuts and Jobs Act Public Utilities, Requested Rate Increase, Revised Increase Due Effects of 2017 Tax Cuts and Jobs Act Asset Acquisition [Domain] Asset Acquisition [Domain] [Domain] for Asset Acquisition [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Operating Segments Operating Segments [Member] Other Other Operating Activities, Cash Flow Statement Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] MAIT Mid-Atlantic Interstate Transmission, LLC [Member] Mid-Atlantic Interstate Transmission, LLC [Member] Asset Class [Axis] Asset Class [Axis] EE&C Phase IV Energy Efficiency and Conservation Phase IV [Member] Energy Efficiency and Conservation Phase IV Adjustments to reconcile net income to net cash from operating activities- Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Customers Accounts Receivable, before Allowance for Credit Loss, Current Basic - Continuing Operations (in dollars per share) Income from continuing operations, basic (in dollars per share) Income (Loss) from Continuing Operations, Per Basic Share Litigation Case [Axis] Litigation Case [Axis] Settlements, Net Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset And (Liability) Settlements Fair value measurement with unobservable inputs reconciliation recurring basis asset and (liability) settlements total. Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Other Receivables Other Receivables Common stock, shares outstanding (in shares) Beginning balance, (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Energy consumption reduction targets Public Utilities, Approved Energy Consumption Reduction Targets Public Utilities, Approved Energy Consumption Reduction Targets Incremental increase to uncollectible expense due to Covid-19 Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease) Revolving Credit Facility Revolving Credit Facility [Member] INCOME BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Subsequent Event Subsequent Event [Member] OHIO OHIO Common stock, shares authorized (in shares) Common Stock, Shares Authorized Assumed exercise of dilutive stock options and awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Number of enhanced service reliability programs Public Utilities, Number of Approved Enhanced Service Reliability Programs Public Utilities, Number of Approved Enhanced Service Reliability Programs Currently payable long-term debt Long-term Debt and Lease Obligation, Current Number of square miles in service area Service Area Service Area. Special termination costs Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits Segment Financial Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Document Period End Date Document Period End Date Accrued compensation and benefits Increase (Decrease) in Employee Related Liabilities Entity Registrant Name Entity Registrant Name Fair Value Estimate of Fair Value Measurement [Member] Income Statement [Abstract] Income Statement [Abstract] Senior Loans Senior Loans [Member] AOCI AOCI Attributable to Parent [Member] Prepaid taxes and other Increase (Decrease) in Prepaid Expense and Other Assets Less: Undistributed earnings allocated to preferred stockholders Undistributed Continuing Operation Earnings (Loss), Allocation to Participating Securities, Basic Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Adjustments related to intercompany tax sharing Discontinued Operation, Tax Effect of Discontinued Operation, Adjustments Related to Intercompany Tax Sharing Discontinued Operation, Tax Effect of Discontinued Operation, Adjustments Related to Intercompany Tax Sharing Purchases, Derivative Liabilities Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Schedule of Guarantor Obligations Schedule of Guarantor Obligations [Table Text Block] New Jersey NEW JERSEY CURRENT ASSETS: Assets, Current [Abstract] Contribution amount Public Utilities, Contribution Amount Public Utilities, Contribution Amount Yard Creek Generating Plant Yard Creek Generating Plant [Member] Yard Creek Generating Plant Income Tax Authority [Domain] Income Tax Authority [Domain] CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Number of regional transmission centers Number of Regional Transmission Centers Number of Regional Transmission Centers Regulated Transmission Regulated Transmission [Member] Regulated Transmission [Member] Consolidated Entities [Axis] Consolidated Entities [Axis] Other Guarantee Guarantee Type, Other [Member] Accounts payable Increase (Decrease) in Accounts Payable, Trade Amortization period Recovery Program, Amortization Period Recovery Program, Amortization Period Maryland MARYLAND Consolidation Items [Domain] Consolidation Items [Domain] Length of transmission lines Length of Transmission Lines Length of Transmission Lines Income Tax Authority [Axis] Income Tax Authority [Axis] Entity Tax Identification Number Entity Tax Identification Number Late payment charges Late Fee Income Generated by Servicing Financial Assets, Amount Pension and OPEB mark-to-market adjustment Increase (Decrease to Net Periodic Benefit Cost Based on Mark-to-Market Adjustment Increase (Decrease to Net Periodic Benefit Cost Based on Mark-to-Market Adjustment Fair value and related carrying amounts of long-term debt and other long-term obligations Fair value and related carrying amounts of long term debt and other long term obligations [Abstract] Fair value and related carrying amounts of long-term debt and other long-term obligations. Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Trading Symbol Trading Symbol Processes for rate adjustments Public Utilities, Approved Rate Number of Rate Adjustments Public Utilities, Approved Rate Number of Rate Adjustments NUG contracts Non Utility Generation Contract [Member] NUG Contract Member. Schedule of Guarantor Obligations [Table] Schedule of Guarantor Obligations [Table] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Property additions Property additions Payments to Acquire Productive Assets Legal Entity [Axis] Legal Entity [Axis] Accrued interest Increase (Decrease) in Interest Payable, Net Other Proceeds from (Payments for) Other Financing Activities Annual revenue cap for rider for years six through eight Annual Revenue Cap for Rider For Years Six Through Eight Annual Revenue Cap for Rider For Years Six Through Eight Amortized Cost Basis, Unrealized Gains and Losses and Fair Values of Investments in Available-for-sale Securities Debt Securities, Available-for-sale [Table Text Block] Deferred for recovery Allowance for Loan and Loss, Deferred Recovery of Bad Debts Allowance for Loan and Loss, Deferred Recovery of Bad Debts Entity [Domain] Entity [Domain] PROPERTY, PLANT AND EQUIPMENT: Property, Plant and Equipment, Net [Abstract] Less: Undistributed earnings allocated to preferred stockholders Undistributed Discontinued Operation Earnings (Loss), Allocation to Participating Securities, Basic Long-term debt and other long-term obligations Long-term Debt Affiliated Companies Affiliated Entity [Member] Twenty-four month period Twenty-Four Month Period [Member] Twenty-Four Month Period [Member] Waste water discharge permit renewal cycle Commitment, Proposed Regulation, Waste Water Discharge Permit, Renewal Cycle Commitment, Proposed Regulation, Waste Water Discharge Permit, Renewal Cycle Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Pension trust contributions Payment for Pension Benefits Debt securities Debt Securities [Member] Service costs Defined Benefit Plan, Service Cost Asset retirement obligations Asset Retirement Obligations, Noncurrent Asset Acquisition [Axis] Asset Acquisition [Axis] Asset Acquisition [Axis] Beginning Balance, Derivative Assets Ending Balance, Derivative Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Table] City Area Code City Area Code Fair Value Debt Securities, Available-for-sale Discontinued operations (Note 3) Discontinued operations, net of tax Income (loss) from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Annual revenue cap for rider for years three through six Annual Revenue Cap for Rider For Years Three Through Six Annual Revenue Cap for Rider For Years Three Through Six Total operating expenses Costs and Expenses Equity Components [Axis] Equity Components [Axis] Title of 12(b) Security Title of 12(b) Security FERC Ferc [Member] FERC Matters. Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Minimum Minimum Minimum [Member] FES Key Creditor Groups FES Key Creditor Groups [Member] FES Key Creditor Groups [Member] OCC DMR Refund Ohio Consumers Counsel Distribution Modernization Rider Refund [Member] Ohio Consumers Counsel Distribution Modernization Rider Refund [Member] Recovery period for expenditures for cost recovery program Recovery Period For Expenditures For Cost Recovery Program Recovery period for expenditures for cost recovery program. Activity in the allowance for uncollectible accounts on customer receivables Accounts Receivable, Allowance for Credit Loss [Table Text Block] Consolidated Entities [Domain] Consolidated Entities [Domain] Mitchell v. FirstEnergy Corp. Mitchell v. FirstEnergy Corp. [Member] Mitchell v. FirstEnergy Corp. WMB Marketing Ventures, LLC WMB Marketing Ventures, LLC [Member] WMB Marketing Ventures, LLC [Member] RFP term Request for Proposal, Project Term Request for Proposal, Project Term Net periodic costs (credits), including amounts capitalized Defined Benefit Plan, Net Periodic Benefit Cost (Credit) REVENUES: Revenues [Abstract] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] Regulatory assets Regulatory Assets, Noncurrent Settlements, Derivative Assets Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Capping of NOx emissions under CSAPR Capping Of Gas Two Emissions Under Cross State Air Pollution Rule Capping Of Gas Two Emissions Under Cross State Air Pollution Rule Pension and OPEB mark-to-market adjustment Defined Benefit Plan, Plan Assets, Period Increase (Decrease) Including Discontinued Operations Defined Benefit Plan, Plan Assets, Period Increase (Decrease) Including Discontinued Operations Customer [Domain] Customer [Domain] Current assets - discontinued operations Disposal Group, Including Discontinued Operation, Assets, Current MPSC Maryland Public Service Commission [Member] Maryland Public Service Commission [Member] Other paid-in capital Additional Paid in Capital, Common Stock Subsequent Event Type [Domain] Subsequent Event Type [Domain] In service Property, Plant and Equipment, Excluding Construction in Progress Gross amount, excluding construction in progress, of long-lived physical assets used in the normal conduct of business and not intended for resale. Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Assets Assets, Fair Value Disclosure [Abstract] Accrued compensation and benefits Accrued Employee Benefits, Current Corporate/Other and Reconciling Adjustments Intersegment Eliminations [Member] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Period of grid modernization plan Public Utilities, Grid Modernization Plan, Period Public Utilities, Grid Modernization Plan, Period Other operating expenses Other operating expenses Other Cost and Expense, Operating Asset removal costs Payments for Removal Costs Unrealized loss, Derivative Liabilities Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability unrealized gain loss Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability unrealized gain loss. AE Supply Ae Supply [Member] AE Supply. Signal Peak Signal Peak [Member] Signal Peak [Member] Regulatory assets Regulatory Assets Retirement Plan Type [Domain] Retirement Plan Type [Domain] Retirement benefits, net of payments Pension and Other Postretirement Benefits Cost (Reversal of Cost) OTHER INCOME (EXPENSE): Other Nonoperating Income (Expense) [Abstract] Fuel Fuel Costs Period of future observable data to determine contract price Derivative, Contract Price, Period of Future Observable Data Derivative, Contract Price, Period of Future Observable Data Common stock dividend payments Payments of Ordinary Dividends, Common Stock Share Count information: Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Consolidation Items [Axis] Consolidation Items [Axis] Conversion of Series A Convertible Stock Stock Issued During Period, Value, Conversion of Convertible Securities Equity securities Equity Securities [Member] Held-for-sale Disposal Group, Held-for-sale, Not Discontinued Operations [Member] Investment excludes receivables, payables and accrued income Investments Excludes Receivables Payables Deferred Taxes And Accrued Income Investments excludes receivables payables deferred taxes and accrued income. INVESTMENTS: Investments [Abstract] Customers Accounts Receivable, after Allowance for Credit Loss, Current REGULATORY MATTERS Public Utilities Disclosure [Text Block] Cash dividends declared on preferred stock Dividends, Preferred Stock, Cash Beginning Balance, Net Ending Balance, Net Fair Value Fair Value Measurements With Unobservable Inputs Reconciliation Recurring Basis Asset And Liability Net Value Fair value measurements with unobservable inputs reconciliation recurring basis asset and liability net value. Proceeds from asset sales Proceeds from Sale of Property Held-for-sale Reconciliation of changes in the fair value of FTRs contracts Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract] Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax PE PE [Member] PE. Unrecognized tax benefits, portion expected to be resolved in the next fiscal year Unrecognized Tax Benefits, Portion Expected To Be Resolved in the Next Fiscal Year Unrecognized Tax Benefits, Portion Expected To Be Resolved in the Next Fiscal Year Clean Water Act Clean Water Act [Member] Clean Water Act. Disposed of by Sale Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] Goodwill Goodwill Goodwill Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] FET Sub-limits Guarantor Subsidiaries [Member] Purchased power Utilities Operating Expense, Purchased Power ATSI ATSI [Member] ATSI. Other Receivables Other Other Receivables [Member] Other receivables. Accrued taxes Increase (Decrease) in Income Taxes Payable Regulatory Matters [Table] Regulatory Matters [Table] Regulatory matters. Dividends declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Face amount of debt Debt Instrument, Face Amount Level 2 Fair Value, Inputs, Level 2 [Member] Prepaid taxes and other Other Assets, Current Liabilities Liabilities, Fair Value Disclosure [Abstract] Unrecognized tax benefits from worthless stock deduction Unrecognized Tax Benefits, Increase Resulting from Change in Worthless Stock Deduction Reserve, Gross Unrecognized Tax Benefits, Increase Resulting from Change in Worthless Stock Deduction Reserve, Gross Number of enhanced service reliability programs Public Utilities, Number of Enhanced Service Reliability Programs Public Utilities, Number of Enhanced Service Reliability Programs Asset Class [Domain] Asset Class [Domain] Fair value, assets Assets, Fair Value Disclosure Equity [Abstract] Equity [Abstract] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Discontinued Operations Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Financial Guarantee Financial Guarantee [Member] Basic - Discontinued Operations (in dollars per share) Discontinued operations, basic (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share Entity Central Index Key Entity Central Index Key Transmission Electric Transmission [Member] Entity Emerging Growth Company Entity Emerging Growth Company Parent, the Utilities, FET and Certain Subsidiaries [Member] Parent, the Utilities, FET and Certain Subsidiaries [Member] Parent, the Utilities, FET and Certain Subsidiaries Short-term borrowings, net Repayments of Short-term Debt Fair Value of Financial Instruments [Line Items] Fair Value of Financial Instruments [Line Items] Fair Value of Financial Instruments. Credit Facility [Domain] Credit Facility [Domain] Derivative Contract Type [Domain] Derivative Contract [Domain] Diluted, in shares Weighted average number of diluted shares outstanding Weighted Average Number of Shares Outstanding, Diluted Litigation Case [Domain] Litigation Case [Domain] Basic - Net Income Attributable to Common Stockholders (in dollars per share) Earnings Per Share, Basic Unrecognized tax benefits that would impact effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Settlement consideration Deconsolidation, Settlement Consideration and Services Credit Deconsolidation, Settlement Consideration and Services Credit JCP&L Reliability Plus JCP&L Reliability Plus [Member] JCP&L Reliability Plus [Member] Retirement benefits Liability, Defined Benefit Plan, Noncurrent Charged to other accounts Accounts Receivable, Allowance for Credit Loss, Recovery Fair Value Inputs, RTO Auction Clearing Prices (in $/MWH) Fair Value Inputs, RTO Auction Clearing Prices Fair Value Inputs, RTO Auction Clearing Prices CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Loss (gain) on disposal, net of tax (Note 3) Loss from discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Common stock Common Stock, Value, Outstanding Disposal Groups, Including Discontinued Operations Disposal Groups, Including Discontinued Operations [Table Text Block] Net cash provided from financing activities Net Cash Provided by (Used in) Financing Activities Long-term debt Debt redemptions Repayments of Long-term Debt Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Wholesale sales Wholesale Sales [Member] Wholesale Sales [Member] Reduction in revenue Tax Cuts and Jobs Act, Change in Tax Rate, Refund of Revenue Tax Cuts and Jobs Act, Change in Tax Rate, Refund of Revenue Preferred stock dividend payments Payments of Ordinary Dividends, Preferred Stock and Preference Stock Total other property and investments Long-term Investments Distribution Services and Retail Generation Electricity, US Regulated [Member] Disposal Group Name [Axis] Disposal Group Name [Axis] Other Other Long-term Investments The Ohio Companies CEI, OE and TE [Member] CEI, OE and TE [Member] WVPSC Public Service Commission of West Virginia [Member] Public Service Commission of West Virginia [Member] Restricted cash Restricted Cash, Current Retail generation Retail Generation [Member] Retail Generation [Member] OTHER COMPREHENSIVE INCOME (LOSS): Other Comprehensive Income Loss [Abstract] OTHER COMPREHENSIVE INCOME:. Time period of the program Public Utilities, Meter Deployment Program Period Public Utilities, Meter Deployment Program Period Discontinued Operations, Disposed of by Means Other than Sale Discontinued Operations, Disposed of by Means Other than Sale [Member] Number of RFP's Number of Requests For Proposal Number of Requests For Proposal Retirement Benefits [Abstract] Retirement Benefits [Abstract] Modernization and Improvement Program For Coal-Fired Boilers Modernization and Improvement Program For Coal-Fired Boilers [Member] Modernization and Improvement Program For Coal-Fired Boilers Related Party Transaction [Axis] Related Party Transaction [Axis] Receivable [Domain] Receivable [Domain] Purchases of investment securities held in trusts Payments to Acquire Debt Securities, Available-for-sale Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Derivative Assets Derivative Assets [Member] Derivative Assets. COMPREHENSIVE INCOME Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Other Other Customers [Member] Other Customers [Member] Amount of code of conduct payment Violation of Code of Conduct Payment, Amount Violation of Code of Conduct Payment, Amount Short-term borrowings Short-term Debt Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items] Gain (loss) on disposal of FES and FENOC, net of tax Deconsolidation, Gain (Loss), Amount Short-Term Borrowings/Revolving Credit Facilities, Long-Term Debt and Other Long-Term Obligations Debt, Policy [Policy Text Block] Short-term cash investments held for sale Cash and Cash Equivalents, Held-for-Sale, Fair Value Disclosure Cash and Cash Equivalents, Held-for-Sale, Fair Value Disclosure Public Utilities, Regulatory Proceeding [Domain] Public Utilities, Regulatory Proceeding [Domain] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Litigation Status [Axis] Litigation Status [Axis] Loss Contingencies By Claims [Axis] Loss Contingencies By Claims [Axis] Loss Contingencies By Claims. Number of meters to be deployed Public Utilities, Number of Meters to be Deployed Public Utilities, Number of Meters to be Deployed Segment Reporting [Abstract] Segment Reporting [Abstract] Regulation of Waste Disposal Regulation Of Waste Disposal [Member] Regulation Of Waste Disposal. ORGANIZATION AND BASIS OF PRESENTATION Basis of Presentation and Significant Accounting Policies [Text Block] Environmental liabilities former gas facilities Environmental Liabilities Former Gas Facilities Environmental Liabilities Former Gas Facilities. Total stockholders’ equity Beginning balance Ending balance Stockholders' Equity Attributable to Parent Property, plant and equipment in service net of accumulated provision for depreciation Net Plant Excluding Construction Work In Progress Amount, net of accumulated depreciation of long-lived physical assets, excluding construction in progress, used in the normal conduct of business and not intended for resale. Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Net assets (liabilities) Fair Value Of Assets (Liabilities) Net Fair value of assets and liabilities net. Total liabilities and capitalization Liabilities and Equity Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax INCOME TAXES Income Tax Disclosure [Text Block] Total noncurrent liabilities Liabilities, Noncurrent Estimated lost distribution revenue Public Utilities, Estimated Lost Distribution Revenue Public Utilities, Estimated Lost Distribution Revenue Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Amount of requested rate increase (decrease) (percent) Public Utilities, Requested Rate Increase (Decrease), Percentage Period to file new depreciation study Public Utilities, Enhanced Service Reliability Program, Period to File New Depreciation Study Public Utilities, Enhanced Service Reliability Program, Period to File New Depreciation Study Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Financial Instrument [Axis] Financial Instrument [Axis] Benefits from accelerated amortization of certain investment tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Amount Shares excluded from the calculation of diluted shares outstanding, in shares Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Total deferred charges and other assets Deferred Charges and Other Assets, Noncurrent Deferred Charges and Other Assets, Noncurrent Wavier of DSIC Cap Wavier of Distribution System Improvement Charge Cap [Member] Wavier of Distribution System Improvement Charge Cap [Member] Requested increase to ROE Public Utilities, Requested Return on Equity, Percentage Distribution Platform Modernization Plan Distribution Platform Modernization Plan [Member] Distribution Platform Modernization Plan [Member] CAPITALIZATION: Capitalization, Long-term Debt and Equity [Abstract] Equity Component [Domain] Equity Component [Domain] Investments - held for sale (Note 10) Disposal Group, Including Discontinued Operation, Investments Disposal Group, Including Discontinued Operation, Investments Pennsylvania Companies Pennsylvania Companies [Member] Pennsylvania Companies consist of ME, PN, Penn and WP Regulatory Matters, Secondary [Axis] Regulatory Matters, Secondary [Axis] Regulatory Matters, Secondary [Axis] Entity Address, Address Line One Entity Address, Address Line One Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Total net property, plant and equipment Property, Plant and Equipment, Net Investments - held for sale Disposal Group, Including Discontinued Operation, Assets Revenue Revenue from Contract with Customer [Policy Text Block] OVEC OVEC [Member] OVEC [Member] Twelve month period Twelve Month Period [Member] Twelve Month Period [Member] Unrealized loss, Net Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Unrealized Gain Loss Fair value measurement with unobservable inputs reconciliation recurring basis unrealized gain (loss) total. Cost of charging equipment rebates Public Utilities, Requested Electric Vehicle Program, Cost of Charging Equipment Rebates Public Utilities, Requested Electric Vehicle Program, Cost of Charging Equipment Rebates NET INCOME NET INCOME Net income Net Income (Loss) Attributable to Parent Entity Address, State or Province Entity Address, State or Province TrAIL Trail [Member] TRAIL. Other Other Liabilities, Current Delivery Capital Recovery Rider Delivery Capital Recovery Rider [Member] Delivery Capital Recovery Rider [Member] Plant capacity (in MW's) Megawatts of net demonstrated capacity of competitive segment Plant Capacity Plant Capacity Changes in current assets and liabilities- Increase (Decrease) in Operating Assets [Abstract] Investment, Name [Domain] Investment, Name [Domain] Other comprehensive loss, net of tax Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax Internal Customers Internal Customers [Member] Internal Customers [Member] Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Total current assets Assets, Current Residential Residential Customers [Member] Residential Customers [Member] EARNINGS PER SHARE OF COMMON STOCK (Note 4): Earnings Per Share [Abstract] Earnings Per Share [Abstract] Pension and OPEB mark-to-market adjustment (Note 5) Defined Benefit Plan, Plan Assets, Period Increase (Decrease) PROPERTY, PLANT AND EQUIPMENT, NET - HELD FOR SALE (NOTE 9) Disposal Group, Including Discontinued Operation, Property, Plant and Equipment Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Debt securities held for sale Debt Securities, Held-for-sale Debt Securities, Held-for-sale Defined Benefit Pension & OPEB Plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Disposal Group Name [Domain] Disposal Group Name [Domain] Stockholders’ equity- Stockholders' Equity Attributable to Parent [Abstract] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Entity Interactive Data Current Entity Interactive Data Current Entity Common Stock Shares Outstanding Entity Common Stock, Shares Outstanding FirstEnergy FE Parent Company [Member] Proposed goal to reduce CO2 pollution (percent) Proposed Action, Reduction in Power Plants Carbon Pollution, Percentage Proposed Action, Reduction in Power Plants Carbon Pollution, Percentage Other/Corporate Other Business Operations [Member] Other Business Operations [Member]. Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Income available to common stockholders, dilutive Net Income (Loss) Available to Common Stockholders, Diluted Number of phases under the EPA’s CAIR for reductions of Sulfur Dioxide and Mono-Nitrogen Oxides Phases Phases Contributions by employer Defined Benefit Plan, Plan Assets, Contributions by Employer FEV FEV [Member] FEV [Member] Capping of SO2 Emissions Under CSAPR Capping Of Gas One Emissions Under Cross State Air Pollution Rule Capping Of Gas One Emissions Under Cross State Air Pollution Rule Proposed penalty amount Loss Contingency, Estimate of Possible Loss National Ambient Air Quality Standards National Ambient Air Quality Standards [Member] National Ambient Air Quality Standards. Common Stock Common Stock [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Product and Service [Domain] Product and Service [Domain] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Settlement agreement and tax sharing payments to the FES Debtors Amount Paid to Settle Agreements and Tax Sharing Payments to Subsidiary Debtors Amount Paid to Settle Agreements and Tax Sharing Payments to Subsidiary Debtors EPA Environmental Protection Agency [Member] Environmental Protection Agency [Member] Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Future Recovery of Incremental Costs Future Recovery of Incremental Costs [Member] Future Recovery of Incremental Costs Income tax benefits on other comprehensive loss Income taxes (benefits) on other comprehensive income (loss) Other Comprehensive Income (Loss), Tax Reduction in CO2 emissions Reduction in Power Plants Carbon Pollution, Percentage Reduction in Power Plants Carbon Pollution, Percentage Charging equipment rebates amortization period Public Utilities, Requested Electric Vehicle Program, Charging Equipment Rebates Amortization Period Public Utilities, Requested Electric Vehicle Program, Charging Equipment Rebates Amortization Period Other income Disposal Group, Including Discontinued Operation, Other Income New LTIIPs New Long-Term Infrastructure Improvement Plans [Member] New Long-Term Infrastructure Improvement Plans [Member] Pre-tax net impact of lost distribution revenues Public Utilities, Estimated Lost Distribution Revenue Before Tax Public Utilities, Estimated Lost Distribution Revenue Before Tax Ownership interest acquired Asset Acquisition, Ownership Interest Acquired Asset Acquisition, Ownership Interest Acquired Conversion of Series A Convertible Stock (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Charged to income Accounts Receivable, Credit Loss Expense (Reversal) Income from continuing operations available to common stockholders Net Income (Loss) from Continuing Operations Available to Common Shareholders, Basic Less — Accumulated provision for depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Curing period Guarantor Obligations, Curing Period Guarantor Obligations, Curing Period Other non-customer revenue Product and Service, Other [Member] Net change in cash, cash equivalents, and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Net periodic credits, recognized in earnings Defined Benefit Plan, Net Periodic Benefit Cost, Excluding Capitalized Amounts Defined Benefit Plan, Net Periodic Benefit Cost, Excluding Capitalized Amounts Total other expense Nonoperating Income (Expense) Investments not required to be disclosed Investments not required to be disclosed Investments not required to be disclosed. Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Less: Preferred dividends Dividends, Preferred Stock Fuel Disposal Group, Including Discontinued Operation, Fuel Costs Disposal Group, Including Discontinued Operation, Fuel Costs Stock Options Share-based Payment Arrangement, Option [Member] Basis of Accounting Basis of Accounting, Policy [Policy Text Block] Basic, in shares Weighted average number of basic shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Public Utility [Axis] Public Utility [Axis] OPERATING EXPENSES: Costs and Expenses [Abstract] Decrease in discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Increase (Decrease) in Discount Rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Increase (Decrease) in Discount Rate Carrying Value Reported Value Measurement [Member] Ownership interest Equity Method Investment, Ownership Percentage Revenue Revenue from Contract with Customer [Text Block] Other current liabilities Increase (Decrease) in Other Current Liabilities DEFERRED CHARGES AND OTHER ASSETS: Deferred Charges And Other Assets [Abstract] Deferred Charges And Other Assets Abstract. Utility customer payment period Revenue from Contract with Customer, Utility Customer Payment Period Revenue from Contract with Customer, Utility Customer Payment Period Approved amount for rider Public Utilities, Annual Revenue Cap for Rider, Approved Amount Public Utilities, Annual Revenue Cap for Rider, Approved Amount Target Period [Axis] Target Period [Axis] Target period. NJBPU New Jersey Board of Public Utilities [Member] New Jersey Board of Public Utilities [Member] Settlement of claims upon emergence Bankruptcy Claims, Amount Paid to Settle Claims Preferred stock dividends declared (in usd per share) Preferred Stock, Dividends Per Share, Declared Total revenues Revenues Revenues Class of Stock [Axis] Class of Stock [Axis] Nuclear fuel disposal trust Nuclear Fuel Disposal Trust Nuclear Fuel Disposal Trust INCOME TAXES Income taxes Income taxes (benefits) Income Tax Expense (Benefit) Cash, cash equivalents, and restricted cash at beginning of period Cash, cash equivalents, and restricted cash at end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Guaranteed Insurance Contract, Type of Guarantee [Domain] Guaranteed Insurance Contract, Type of Guarantee [Domain] Fair value, liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Amount of requested rate increase (decrease) Public Utilities, Requested Rate Increase (Decrease), Amount FTRs Ftrs [Member] Fire steel resources. Diluted - Net Income Attributable to Common Stockholders (in dollars per share) Earnings Per Share, Diluted Sales of investment securities held in trusts Proceeds from Sale of Debt Securities, Available-for-sale Amounts reclassified from AOCI Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Amount of approved annual rate increase Public Utilities, Approved Annual Rate Increase (Decrease), Amount Public Utilities, Approved Annual Rate Increase (Decrease), Amount LIABILITIES AND CAPITALIZATION Liabilities And Capitalization [Abstract] Liabilities And Capitalization Abstract. DSP June 2019- May 2023 Default Service Plan June 2019- May 2023 [Member] Default Service Plan June 2019- May 2023 [Member] Income tax expense Discontinued Operation, Tax Effect of Discontinued Operation Demand reduction targets Public Utilities, Approved Demand Reduction Targets Public Utilities, Approved Demand Reduction Targets Energy Conservation, Economic Development and Job Retention Energy Conservation, Economic Development and Job Retention [Member] Energy Conservation, Economic Development and Job Retention [Member] General taxes Disposal Group, Including Discontinued Operation, General Taxes Disposal Group, Including Discontinued Operation, General Taxes Accrual for environmental loss contingencies Accrual for Environmental Loss Contingencies Realized Losses Debt and Equity Securities, Realized Losses Debt and Equity Securities, Realized Losses Nuclear plant decommissioning trusts Decommissioning Fund Investments Sale proceeds Debt and Equity Securities, Realized Gain (Loss), Sales Proceeds Debt and Equity Securities, Realized Gain (Loss), Sales Proceeds Provision for depreciation Depreciation Depreciation Expected cost of the program Public Utilities, Expected Cost of the Program Public Utilities, Expected Cost of the Program Related Party Transaction [Domain] Related Party Transaction [Domain] Book value Asset Acquisition, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Asset Acquisition, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Worthless stock deduction Effective Income Tax Rate Reconciliation, Deduction, Worthless Stock, Amount Effective Income Tax Rate Reconciliation, Deduction, Worthless Stock, Amount Yard Creek Generating Facility Yard Creek Generating Facility [Member] Yard Creek Generating Facility Series A Convertible Preferred Stock Convertible Preferred Stock [Member] Nuclear Plant Matters Nuclear Plant Matters [Member] Nuclear Plant Matters. Distribution Modernization Rider Distribution Modernization Rider [Member] Distribution Modernization Rider [Member] Maximum amount borrowed under revolving credit facility Line of Credit Facility, Maximum Borrowing Capacity Utility Plant [Domain] Utility Plant [Domain] Purchase Agreement with Subsidiary of LS Power Purchase Agreement with Subsidiary of LS Power [Member] Purchase Agreement with Subsidiary of LS Power [Member] FES FES [Member] First Energy Solutions Corp. Decoupling Rider Decoupling Rider [Member] Decoupling Rider Maximum Maximum Maximum [Member] Security Exchange Name Security Exchange Name Quantitative Information for Level 3 Valuation Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Cash dividends declared on common stock Dividends, Common Stock, Cash Approved ROE Public Utilities, Approved Return on Equity, Percentage Accumulated Deficit Retained Earnings [Member] Measurement Basis [Axis] Measurement Basis [Axis] Amortized losses on derivative hedges Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value and Related Carrying Amounts of Long-term Debt and Other Long-term Obligations Fair Value And Related Carrying Amounts Of Long Term Debt And Other Long Term Obligations [Table Text Block] Fair value and related carrying amounts of long-term debt and other long-term obligations. Effective tax rate (percent) Effective Income Tax Rate Reconciliation, Percent Components of Net Periodic Benefit Costs Schedule of Net Benefit Costs [Table Text Block] Net cash used for investing activities Net Cash Provided by (Used in) Investing Activities Pending Litigation Pending Litigation [Member] Beginning balance Ending balance Accounts Receivable, Allowance for Credit Loss Signal Peak, Global Rail and Affiliates Signal Peak, Global Rail and Affiliates [Member] Signal Peak, Global Rail and Affiliates [Member] Recovery of deferred, incremental uncollectible and other related costs Public Utilities, Recovery of Deferred, Incremental Uncollectible and Other Related Costs Public Utilities, Recovery of Deferred, Incremental Uncollectible and Other Related Costs Industrial Industrial Customers [Member] Industrial Customers [Member] Enhanced service reliability program renewal period Public Utilities, Enhanced Service Reliability Program, Rate Case Renewal Period Public Utilities, Enhanced Service Reliability Program, Rate Case Renewal Period Outstanding guarantees and other assurances aggregated Guarantor Obligations, Current Carrying Value ME Metropolitan Edison Company [Member] Metropolitan Edison Company NONCURRENT LIABILITIES: Liabilities, Noncurrent [Abstract] Document Transition Report Document Transition Report Amortization (deferral) of regulatory assets, net Amortization (Deferral) Of Regulatory Asset Amortization (Deferral) Of Regulatory Asset Corporate debt securities Corporate Debt Securities [Member] OPEB Other Postretirement Benefits Plan [Member] Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations and Disposal Groups [Abstract] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Litigation Status [Domain] Litigation Status [Domain] Utilities and FET Regulated Distribution and Regulated Transmission [Member] Regulated Distribution and Regulated Transmission [Member] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Capitalized cost of equity Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity Derivative Liabilities Derivative Liabilities [Member] Derivative Liabilities. Unrecognized tax benefits from worthless stock deduction, net of tax Unrecognized Tax Benefits, Increase Resulting from Change in Worthless Stock Deduction Reserve, Net of Tax Unrecognized Tax Benefits, Increase Resulting from Change in Worthless Stock Deduction Reserve, Net of Tax Adverse power contract liability Adverse Power Contract Liability Power purchase contract liability. Pension Pension Plan [Member] EARNINGS PER SHARE OF COMMON STOCK Earnings Per Share [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] PPUC Pennsylvania Public Utility Commission [Member] Pennsylvania Public Utility Commission [Member] Income tax expense (benefit) including worthless stock deduction Income Tax Expense (Benefit) from Deconsolidation, Gain (Loss) Including Worthless Stock Deduction Income Tax Expense (Benefit) from Deconsolidation, Gain (Loss) Including Worthless Stock Deduction CURRENT LIABILITIES: Liabilities, Current [Abstract] CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Mark-to-market adjustment Defined Benefit Plan, Mark-to-Market Adjustment, Net Defined Benefit Plan, Mark-to-Market Adjustment, Net Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Company posted collateral related to net liability positions Company Posted Collateral Related To Net Liability Positions Company Posted Collateral Related To Net Liability Positions. Guarantor Obligations [Line Items] Guarantor Obligations [Line Items] Recurring Fair Value, Recurring [Member] New Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] FES and FENOC FES and FENOC [Member] FES and FENOC [Member] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] EPS of Common Stock Earnings Per Share, Basic [Abstract] Regulatory Agency [Domain] Regulatory Agency [Domain]