(Gain) loss on sales of assets, net (Note 17) Gain (Loss) On Disposition Of Non-Core Assets Gain (Loss) On Disposition Of Non-Core Assets Accrued liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Investments in Debt and Equity Securities Investment, Policy [Policy Text Block] Debt Instrument, Redemption, Period Four Debt Instrument, Redemption, Period Four [Member] Postretirement Benefit Obligations Postemployment Benefit Plans, Policy [Policy Text Block] Reorganization Income (Expense), net: Reorganizations [Abstract] Commodity derivatives Commodity Contract [Member] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Schedule of Expected Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] Award Timing Predetermined Award Timing Predetermined [Flag] TLB-1 TLB-1 Facility [Member] TLB-1 Facility Entity File Number Entity File Number Additional paid-in capital Additional Paid-in Capital [Member] Equity in earnings of TES Income (Loss) from Subsidiaries, before Tax Other Other Noncash Income (Expense), Miscellaneous Other Noncash Income (Expense), Miscellaneous Nuclear PTC, carrying value Nuclear Production Tax Credits, Carrying Value Nuclear Production Tax Credits, Carrying Value Tabular List, Table Tabular List [Table Text Block] Income tax benefit (expense) Other Comprehensive Income (Loss), Tax Target allocations Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Payment of professional fees Payment Of Professional Fees, Restricted Cash And Cash Equivalents Payment Of Professional Fees, Restricted Cash And Cash Equivalents Nuclear Decommissioning Trust Funds Schedule of Investments [Text Block] Asset retirement obligations and accrued environmental costs Liabilities Subject to Compromise, Asset Retirement Obligations And Accrued Environmental Costs Liabilities Subject to Compromise, Asset Retirement Obligations And Accrued Environmental Costs Recently Adopted Accounting Pronouncements/ Recent Accounting Pronouncements Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Schedule of Recurring Fair Value Measurements Fair Value, by Balance Sheet Grouping [Table Text Block] Position [Axis] Position [Axis] Adjustment to Compensation: Adjustment to Compensation [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Western Gas Book Western Gas Book [Member] Western Gas Book Revenue Revenue from Contract with Customer [Text Block] Percentage of adjusted EBITDA Debt Instrument, Covenant, Adjusted Earnings Before Interest Taxes Depreciations And Amortization, Maximum Percentage Debt Instrument, Covenant, Adjusted Earnings Before Interest Taxes Depreciations And Amortization, Maximum Percentage Debt Liabilities Subject to Compromise, Debt Liabilities Subject to Compromise, Debt Current income taxes Current Income Tax Expense (Benefit) Accounts payable and other accrued liabilities: Accounts Payable and Accrued Liabilities [Abstract] Adjustment to Compensation, Amount Adjustment to Compensation Amount Concentration risk percentage Concentration Risk, Percentage Pension Plan Pension Benefits Pension Plan [Member] Unamortized deferred financing costs and original issuance discounts Issuance of equity for backstop premium Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Other assets Increase (Decrease) in Other Operating Assets Principles of Consolidation Consolidation, Policy [Policy Text Block] Contributions from member Proceeds from Contributions from Affiliates Nuclear decommissioning trust funds gain (loss), net (Note 6) Nuclear decommissioning trust funds gain (loss), net Gain (Loss) On Nuclear Decommissioning Trust Funds, Net Gain (Loss) On Nuclear Decommissioning Trust Funds, Net Stock-based compensation (Note 13) Share-Based Payment Arrangement, Noncash Expense Commingled debt securities Defined Benefit Plan, Commingled Debt Securities [Member] Defined Benefit Plan, Commingled Debt Securities Employee Stock Option Share-Based Payment Arrangement, Option [Member] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Impairment Property, Plant and Equipment, Impairment [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Payment of claims under other prepetition secured indebtedness Payment Of Claims Under Other Prepetition Secured Indebtedness Payment Of Claims Under Other Prepetition Secured Indebtedness Nuclear insurance, coverage Nuclear Insurance, Coverage Nuclear Insurance, Coverage Percent Effective Income Tax Rate Reconciliation, Percent [Abstract] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Threshold One Threshold One [Member] Threshold One Total Stockholders' Equity Total Stockholders' Equity Equity, Attributable to Parent Other Comprehensive Income (Loss) Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] Schedule of Components of Depreciation, Amortization and Accretion Expense Property, Plant and Equipment [Table Text Block] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Surety Bond Surety Bond [Member] Common equity from member's equity exchange (in shares) Stock Issued During Period, Shares, New Issues Gain on debt discharge Gain on debt discharge Debtor Reorganization Items, Gain (Loss) On Discharge Of Debt Debtor Reorganization Items, Gain (Loss) On Discharge Of Debt Improper payment Loss Contingency, Improper Payment Loss Contingency, Improper Payment Thereafter Acquired Fuel Supply Contract Liabilities, Expected Amortization, After Year Five Acquired Fuel Supply Contract Liabilities, Expected Amortization, After Year Five TEC TEC [Member] TEC AWS Data Campus AWS Data Campus [Member] AWS Data Campus LCF Stand-alone Letter of Credit Facility [Member] Stand-alone Letter of Credit Facility Concentrations of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Unrealized gain on qualifying derivatives Deferred Tax Liabilities, Derivatives Liabilities and Equity Liabilities and Equity Liabilities and Equity [Abstract] State, expirations 2026 - 2041 State and Local Jurisdiction [Member] Cover [Abstract] Cash equivalents, Fair Value Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Proceeds from rights offering Proceeds From Rights Offering Proceeds From Rights Offering Nuclear Fuel Contract Intangible Assets Nuclear Fuel Contract Intangible Assets [Member] Nuclear Fuel Contract Intangible Assets Maximum Maximum [Member] Finite-Lived Assets Property, Plant and Equipment, Net [Abstract] Amortized Cost Decommissioning Fund Investments, Amortized Cost Decommissioning Fund Investments, Amortized Cost Adjustments to long-term debt: Long-Term Debt, Unclassified [Abstract] Less: Net income (loss) attributable to noncontrolling interest Net income (loss) attributable to noncontrolling interest Net Income (Loss) Attributable to Noncontrolling Interest Fair Value Debt Securities, Available-for-Sale, Unrealized Loss Position Pennsylvania PENNSYLVANIA Common equity from member’s equity exchange Stock Issued During Period, Value, Member’s Equity Exchange Stock Issued During Period, Value, Member’s Equity Exchange Professional fees Debtor Reorganization Items, Professional Fees Debtor Reorganization Items, Professional Fees Issuance of equity for backstop premium Issuance Of Equity For Backstop Premium Issuance Of Equity For Backstop Premium Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Retrospective premiums, maximum assessment Retrospective Premiums, Maximum Assessment Retrospective Premiums, Maximum Assessment Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based 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Reconciliation, Reorganization Adjustments, Amount Other Postretirement Benefit Plan, Obligation Other Postretirement Benefit Plan, Obligation [Member] Other Postretirement Benefit Plan, Obligation Less: Comprehensive income (loss) attributable to noncontrolling interest Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Asset Retirement Obligations Asset Retirement Obligation [Policy Text Block] Prior service cost (credit) Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Letter of Credit Letter of Credit [Member] Energy Revenues Energy Revenues [Member] Energy Revenues Repurchase of noncontrolling interest Repurchase of noncontrolling interest Payments to Noncontrolling Interests Less: Earnings Per Share, Deductions [Abstract] Earnings Per Share, Deductions Schedule of Stock-based Compensation Expense Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Postretirement benefit obligations Liability Subject to Compromise, Pension and Other Postretirement Benefit Plan, Benefit Obligation Capitalized software Software and Software Development Costs [Member] Document Fiscal Period Focus Document Fiscal Period Focus Rate of compensation increase Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Adjusted EBITDA Adjusted Earnings Before Interest Taxes Depreciations And Amortization Adjusted Earnings Before Interest Taxes Depreciations And Amortization 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] Award Timing Method Award Timing Method [Text Block] Litigation Case [Domain] Litigation Case [Domain] Benefit obligation / Accumulated benefit obligation Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation Award Type Award Type [Axis] Acquired fuel supply contract liabilities (Note 17) Contract with Customer, Liability, Noncurrent Reinstatement of liabilities subject to compromise Reinstatement Of Liabilities Subject To Compromise, Accounts Payable And Other Accrued Liabilities, Current Reinstatement Of Liabilities Subject To Compromise, Accounts Payable And Other Accrued Liabilities, Current Parent Company Parent Company [Member] Debt instrument, prepayment penalty percentage Debt Instrument, Prepayment Penalty, Percentage Debt Instrument, Prepayment Penalty, Percentage Schedule of Unaudited Pro Forma Financial Information Business Combination, Pro Forma Information [Table Text Block] Stock-Based Compensation Share-Based Payment Arrangement [Policy Text Block] Other Securities, Growth Portfolio Defined Benefit Plan, Other Securities, Growth Portfolio [Member] Defined Benefit Plan, Other Securities, Growth Portfolio Trading Symbol Trading Symbol Materials and supplies, net Inventory, Parts and Components, Net of Reserves Business Combinations Business Combination [Policy Text Block] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Changes in valuation allowances Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Member's Equity Member Units [Member] Number of groups that challenged the EPA CCR Rule Loss Contingency, Number Of Industry Groups Loss Contingency, Number Of Industry Groups Entity Address, City or Town Entity Address, City or Town Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Credit exposure, net Credit Derivative, Maximum Exposure, Undiscounted, Net Credit Derivative, Maximum Exposure, Undiscounted, Net Restricted stock units Restricted Stock Units (RSUs) [Member] Statement of Income Location, Balance [Domain] Statement of Income Location, Balance [Domain] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Consideration transferred Business Combination, Consideration Transferred Sales proceeds of NDT funds investments Proceeds From Sale Of Nuclear Decommissioning Trust Funds Proceeds From Sale Of Nuclear Decommissioning Trust Funds Entity Emerging Growth Company Entity Emerging Growth Company 2028 Long-Term Debt, Maturity, Year Three Total accumulated other comprehensive income Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Liabilities, Collateral (Posted) Received Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset Condensed Financial Information of Parent Company Only Disclosure Condensed Financial Information of Parent Company Only Disclosure [Text Block] Revolving credit facility repayments (Note 10) Revolving credit facility repayments (Note 10) Repayments of Lines of Credit Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Net change in Restricted cash and cash equivalents Restricted Cash and Cash Equivalent Schedule of Acquired Contract Liabilities, Future Amortization Expense Schedule of Acquired Contract Liabilities, Future Amortization Expense [Table Text Block] Schedule of Acquired Contract Liabilities, Future Amortization Expense 2026 Defined Benefit Plan, Expected Future Benefit Payment, Year One Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations, Abandonment Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations, Abandonment [Member] Reorganization, Chapter 11 [Domain] Reorganization, Chapter 11 [Domain] Shares outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Gain (loss) on asset sales, net Gain (Loss) on Disposition of Other Assets Retirement Plan Assumptions [Domain] Retirement Plan Assumptions [Domain] Retirement Plan Assumptions [Domain] Nuclear PTC, cash consideration Proceeds From Sale of Nuclear Production Tax Credits Proceeds From Sale of Nuclear Production Tax Credits Accretion expense Accretion Expense, Including Asset Retirement Obligations Schedule of Components of Operating Revenues Disaggregation of Revenue [Table Text Block] Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Reorganization (income) expense, net (Note 20) Reorganization Items, Cash Flow Impact Reorganization Items, Cash Flow Impact Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Plus: Cash and cash equivalents and Restricted cash and cash equivalents Plus: Cash and cash equivalents and Restricted cash and cash equivalents Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Excluding Professional Fees Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Excluding Professional Fees Surety bonds Guarantor Obligations, Current Carrying Value Bitcoin revenue Cryptocurrency Revenue Cryptocurrency Revenue Derivative Instruments and Hedging Activities Disclosure [Abstract] Proceeds from issuance or sale of equity Proceeds from Issuance or Sale of Equity Change in benefit obligation Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Percentage share of storage costs Loss Contingency, Percentage Share Of Storage Costs Loss Contingency, Percentage Share Of Storage Costs Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date TLC TLC Facility [Member] TLC Facility Income tax benefit (expense) (Note 4) Income tax benefit (expense) Income Tax Expense (Benefit) Inventory Adjustments: Inventory Adjustments [Abstract] Maximum adjusted EBITDA Debt Instrument, Covenant, Adjusted Earnings Before Interest Taxes Depreciations And Amortization, Maximum Threshold Debt Instrument, Covenant, Adjusted Earnings Before Interest Taxes Depreciations And Amortization, Maximum Threshold Applicable interest rate Debt Instrument, Basis Spread on Variable Rate Nuclear decommissioning trust funds investment purchases (Note 6) Payments to Acquire Investments to be Held in Decommissioning Trust Fund Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Fair Value Hierarchy and NAV [Axis] Defined Benefit Plan, Fair Value of Plan Assets by Measurement [Axis] Fair Value Hierarchy and NAV [Axis] Gross Value Property, Plant and Equipment, Gross Treasury Stock and Retirement of Treasury Shares Stockholders' Equity, Policy [Policy Text Block] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Net income from reorganization adjustments Net Income From Reorganization Adjustments Net Income From Reorganization Adjustments Acquired fuel supply contract liabilities Business Combination, Recognized Liability Assumed, Contract Liabilities Business Combination, Recognized Liability Assumed, Contract Liabilities Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Secured Notes Secured Notes [Member] Secured Notes Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Acquisitions and Divestitures Mergers, Acquisitions and Dispositions Disclosures [Text Block] Freedom and Guernsey Acquisitions, net (Note 17) Payments to Acquire Businesses, Net of Cash Acquired Total federal tax Income Tax Paid, Federal, after Refund Received All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Nuclear insurance, maximum deferred premiums Nuclear Insurance, Maximum Deferred Premiums Nuclear Insurance, Maximum Deferred Premiums Class of Treasury Stock [Table] Class of Treasury Stock [Table] Contingencies Commitments and Contingencies, Policy [Policy Text Block] Warrants (in shares) Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants Balance at the beginning of the period (in shares) Balance at the end of the period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Commitments and Contingencies Disclosure [Abstract] Litigation settlement, gain Litigation Settlement, Gain Non-nuclear Non-Nuclear Fuel [Member] Non-Nuclear Fuel Net cash provided by (used in) operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Retirement of treasury stock Share retirements, total amount Treasury Stock, Retired, Cost Method, Amount Fixed-cost per day payments (dollars per MWd) Fixed-Cost Price Per MW, Per Day Fixed-Cost Price Per MW, Per Day Estimated Useful Life (years) Property, Plant and Equipment, Useful Life Subsequent Event Subsequent Event [Member] Schedule of Significant Inputs and Assumptions of Fair Value Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Other assets Business Combination, Recognized Asset Acquired, Other Asset, Current Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Depreciation expense Depreciation Talen Montana Pension Plan Talen Montana Pension Plan [Member] Talen Montana Pension Plan Debt instrument, fixed charge coverage ratio Debt Instrument, Covenant, Fixed Charge Coverage Ratio, Minimum Debt Instrument, Covenant, Fixed Charge Coverage Ratio, Minimum Debt Instrument, Redemption, Period Three Debt Instrument, Redemption, Period Three [Member] Capacity revenues Operating Revenue, Capacity [Member] Operating Revenue, Capacity Asset Business Combination, Recognized Asset Acquired, Asset [Abstract] Liabilities, Gross Derivative Instruments Derivative Liability, Subject to Master Netting Arrangement, before Offset Capacity Revenue, Other Capacity Revenue, Other [Member] Capacity Revenue, Other Equity Components [Axis] Equity Components [Axis] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Reorganization, Chapter 11 [Line Items] Reorganization, Chapter 11 [Line Items] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Cumulus Digital Holdings LLC Cumulus Digital Holdings LLC [Member] Cumulus Digital Holdings LLC Less: Components of Deferred Tax Assets [Abstract] Fair Value, Concentration of Risk, Disclosure Items [Domain] Fair Value, Concentration of Risk, Disclosure Items [Domain] Entity Address, State or Province Entity Address, State or Province Antidilutive Security, Excluded EPS Calculation [Table] Antidilutive Security, Excluded EPS Calculation [Table] 2029 Defined Benefit Plan, Expected Future Benefit Payment, Year Four Total current liabilities Liabilities, Current Other liabilities Liabilities Subject to Compromise, Other Liabilities Schedule of Fair Value of Plan Assets by Measurement Schedule of Fair Value of Plan Assets by Measurement [Table Text Block] Tabular disclosure of the fair value of plan assets of pension plans and/or other employee benefit plans. Inventory [Axis] Inventory [Axis] Individual: Individual [Axis] Net periodic defined benefit cost (credit) Defined Contribution Plan, Cost Issuance of warrants Stock Issued During Period, Value, Equity-Classified Warrants Stock Issued During Period, Value, Equity-Classified Warrants Income Tax Jurisdiction [Domain] Income Tax Jurisdiction [Domain] Schedule of Disaggregation of Asset Retirement Obligations Schedule of Asset Retirement Obligations [Table Text Block] Document Annual Report Document Annual Report Amortization expense Amortization Operation, Maintenance and Development Operation, Maintenance, And Development Costs, Policy [Policy Text Block] Operation, Maintenance, And Development Costs, Policy Cash and cash equivalents Cash equivalents Defined Benefit Plan, Cash and Cash Equivalents [Member] Acquired fuel supply contract liabilities Deferred Tax Assets, Contract Liabilities Deferred Tax Assets, Contract Liabilities Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Ownership percentage, noncontrolling owner Subsidiary, Ownership Percentage, Noncontrolling Owner Entity Interactive Data Current Entity Interactive Data Current Weighted-Average Grant Date Fair Value per Unit Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Unrealized gain (loss) on commodity contracts Commodity contracts Unrealized gain (loss) on commodity derivative contracts Unrealized Gain (Loss) on Commodity Contracts Pennsylvania Minerals Pennsylvania Minerals [Member] Pennsylvania Minerals Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Interest crediting rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Weighted-Average Interest Crediting Rate Overfunded Status Funded status Defined Benefit Plan, Funded (Unfunded) Status of Plan Other Postretirement Benefit Plan, Periodic Benefit 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Predecessor, before Adjustment [Member] Less: asset retirement obligations and accrued environmental costs due within one year Asset Retirement Obligation And Accrued Environmental Costs, Current Asset Retirement Obligation And Accrued Environmental Costs, Current Liquidity portfolio Liquidity Portfolio [Member] Liquidity Portfolio 2027 Defined Benefit Plan, Expected Future Benefit Payment, Year Two Condensed Financial Statements [Table] Condensed Financial Statements [Table] Reinstatement of liabilities subject to compromise Reinstatement Of Liabilities Subject To Compromise, Other Liabilities, Current Reinstatement Of Liabilities Subject To Compromise, Other Liabilities, Current PJM PJM Segment [Member] PJM Segment Schedule of Unrecognized Stock-Based Compensation Expense Share-Based Payment Arrangement, Nonvested Award, Cost [Table Text Block] Other noncurrent assets Net change in Other noncurrent assets Other Assets, Noncurrent Accrued interest Interest Payable, Current Entity Central Key Index Entity Central Index Key Aggregate credit exposure Credit Derivative, Maximum Exposure, Undiscounted PEO Name PEO Name Power generating capacity or generation plant Power Generating Capacity Of Natural Gas Fired Combined Cycle Generation Plant Power Generating Capacity Of Natural Gas Fired Combined Cycle Generation Plant Asset retirement obligations Beginning balance Ending balance Asset Retirement Obligation Schedule of Long-Term Debt Maturities Schedule of Maturities of Long-Term Debt [Table Text Block] Operating revenues Operating revenues Operating Revenue Revenues Realized and unrealized gain (loss) on interest rate contracts Realized and unrealized gain (loss) on derivative instruments Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Supplemental Cash Flow Elements [Abstract] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Cumulus Digital TLF repayment Repayment Of Term Loan 2 Repayment Of Term Loan 2 Defined Benefit Plan [Table] Defined Benefit Plan [Table] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Derivative assets, netting Derivative Asset, Subject to Master Netting Arrangement, Gross Liability and Collateral, Obligation to Return Cash, Offset Schedule of Derivative Instruments in Statement of Financial Position, Fair Value Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Exercise Price Award Exercise Price Coal Energy Related Inventory, Coal Entity Filer Category Entity Filer Category Commodity purchase (sales) derivatives, power and natural gas Derivative, Nonmonetary Notional Amount, Energy Measure Actual benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Inventory, Current [Table] Inventory, Current [Table] Federal income tax at statutory tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Subsequent Event Type [Axis] Subsequent Event Type [Axis] Long Long [Member] ERCOT Assets ERCOT Assets [Member] ERCOT Assets Divestiture consideration Disposal Group, Including Discontinued Operation, Consideration Long-term debt (Notes 10 and 11) Long-term debt Net change in Long-term debt Long-Term Debt, Excluding Current Maturities Restricted Cash and Cash Equivalent [Abstract] Restricted Cash and Cash Equivalent [Abstract] Vesting [Domain] Vesting [Domain] Bonds Bonds [Member] Reclassifications to Consolidated Statements of Operations Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Entity Address, Address Line One Entity Address, Address Line One Payment of accrued interest on debtor-in-possession credit facilities Payment Of Accrued Interest On Debtor-In-Possession Credit Facilities Payment Of Accrued Interest On Debtor-In-Possession Credit Facilities Carrying Value Additional Fair Value Elements [Abstract] Accumulated other comprehensive income (loss) AOCI Attributable to Parent [Member] Exercise of warrants (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Accrued interest Liabilities Subject to Compromise, Accrued Interest Liabilities Subject to Compromise, Accrued Interest Ownership [Axis] Ownership [Axis] Risk Management, Derivative Instruments and Hedging Activities Derivative Instruments and Hedging Activities Disclosure [Text Block] Amortization of prior service cost (credit) Defined Benefit Plan, Amortization of Prior Service Cost (Credit) 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] Fair Value as of Grant Date Award Grant Date Fair Value Fair value of equity Equity Securities, FV-NI, Cost Earnings Per Share, Diluted, by Common Class, Including Two-Class Method [Table] Earnings Per Share, Diluted, by Common Class, Including Two-Class Method [Table] Net operating loss carryforwards Operating Loss Carryforwards Release of restricted cash Release of restricted cash Proceeds From Release Of Restricted Cash Proceeds From Release Of Restricted Cash Noncontrolling interest Adjusted EBITDA Related To Noncontrolling Interest Adjusted EBITDA Related To Noncontrolling Interest Stock-based and other long-term incentive compensation expense Employee Benefits and Share-Based Compensation Schedule of Long-Term Debt Schedule of Long-Term Debt Instruments [Table Text Block] Obligations settled Asset Retirement Obligation, Cash Paid to Settle Derivative Instruments and Hedging Activities Disclosures [Table] Derivative Instruments and Hedging Activities Disclosures [Table] Expected volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Stock units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Debt instrument, amortization interest rate Debt Instrument, Amortization Interest Rate Debt Instrument, Amortization Interest Rate Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Unrecognized stock-based compensation expense Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Oil products Energy Related Inventory, Petroleum Related Party Transaction [Line Items] Related Party Transaction [Line Items] Debt Covenant, Threshold [Domain] Debt Covenant, Threshold [Domain] Debt Covenant, Threshold Long-term debt Less: Fair value of debt Long-Term Debt, Fair Value Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Counterparty Name [Domain] Counterparty Name [Domain] U.S. government debt securities US Government-sponsored Enterprises Debt Securities [Member] Cash paid for reorganization expenses Cash Paid For Certain Reorganization Expenses Cash Paid For Certain Reorganization Expenses Condensed Financial Information Disclosure [Abstract] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Payment to general unsecured creditors trust Issuance Of Members' Equity To Holders Of Claims Under Prepetition Notes And Bonds Issuance Of Members' Equity To Holders Of Claims Under Prepetition Notes And Bonds Investment in TES Investments Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount 2028 Defined Benefit Plan, Expected Future Benefit Payment, Year Three 2030 Acquired Fuel Supply Contract Liabilities, Expected Amortization, Year Five Acquired Fuel Supply Contract Liabilities, Expected Amortization, Year Five Excess fair value ascribed to lenders participating in rights offering Excess Fair Value Ascribed To Lenders Participating In Rights Offering Excess Fair Value Ascribed To Lenders Participating In Rights Offering Other liabilities, current, derecognized Disposal Group, Including Discontinued Operation, Other Liabilities, Current Schedule of Funded Status Changes in Projected 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Keystone [Member] Keystone Derivative liabilities, netting Derivative Liability, Subject to Master Netting Arrangement, Gross Asset and Collateral, Right to Reclaim Cash, Offset Total carrying value Long-term debt Long-Term Debt Legal Entity [Axis] Legal Entity [Axis] Total Assets Total Assets Assets Covenant consolidated series step-ups first lien net leverage ratio Debt Instrument, Covenant, Net Leverage Ratio, Maximum Debt Instrument, Covenant, Net Leverage Ratio, Maximum Cash settlement of restricted stock units Adjustments To Additional Paid In Capital, Cash Settlement Of Restricted Stock Units Adjustments To Additional Paid In Capital, Cash Settlement Of Restricted Stock Units Vested (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Income Taxes Income Tax, Policy [Policy Text Block] Fair value adjustment to Cumulus Digital TLF Fair Value 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Fees, Accounts Payable And Accrued Liabilities Product and Service [Domain] Product and Service [Domain] US Federal - Corporate Domestic Tax Jurisdiction, Corporate [Member] Domestic Tax Jurisdiction, Corporate Asset Retirement Obligation Disclosure [Abstract] Asset Retirement Obligation Disclosure [Abstract] Common rights equity offering, receivable of additional equity, percent Common Rights Equity Offering, Receivable Of Additional Equity, Percent Common Rights Equity Offering, Receivable Of Additional Equity, Percent Income (Loss) Before Income Taxes Net income (loss) Income (Loss) Before Income Taxes Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Schedule of Business Acquisitions, by Acquisition [Table] Business Combination [Table] Total liabilities Liabilities, Fair Value Disclosure Obligations incurred Asset Retirement Obligation, Liabilities Incurred Interest 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securities Equity Securities, FV-NI Gain on derecognition of certain Liabilities subject to compromise Debtor Reorganization Items, Gain (Loss) on Settlement of Other Claims, Net Payment of professional fees Payment Of Professional Fees Payment Of Professional Fees Nuclear decommissioning trust funds (gain) loss, net (excluding interest and fees) (Note 6) Gain (Loss) on Investments Fair value of plan assets Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets Derivatives with financing elements Payments for Derivative Instrument, Financing Activities Interest limitation carryforward Deferred Tax Asset, Interest Carryforward Federal Deferred Federal Income Tax Expense (Benefit) Auditor Name Auditor Name Increase in borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity, Increase Line of Credit Facility, Maximum Borrowing Capacity, Increase Total Net Credit Exposure Total Net Credit Exposure [Member] Total Net Credit Exposure Estimated fair value of liability-classified warrants: Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions and Methodology [Abstract] Environmental Matters, EPA CCR Rule Environmental Matters, EPA CCR Rule [Member] Environmental Matters, EPA CCR Rule Other noncurrent liabilities: Other Liabilities, Noncurrent [Abstract] Fair value adjustment to LMBE-MC TLB Fair Value Adjustment to Term Loan B Fair Value Adjustment to Term Loan B Darby Generating Station Darby Generating Station [Member] Darby Generating Station Cash paid during the period Supplemental Cash Flow Information [Abstract] Schedule of Operating Loss Carryforwards Summary of Operating Loss Carryforwards [Table Text Block] Accounts receivable Business Combination, Recognized Asset Acquired, Receivable, Current Debt instrument, fronting fee, percentage Debt Instrument, Fronting Fee, Percentage Debt Instrument, Fronting Fee, Percentage Debt securities, Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost Other Performance Measure, Amount Other Performance Measure, Amount Inventory [Line Items] Inventory [Line Items] Deferred financing costs Payment of debt issuance costs on exit financing (TLB-1, TLC, and Secured Notes) Payments of Debt Issuance Costs Accounts payable and accrued liabilities Liabilities Subject to Compromise, Accounts Payable and Accrued Liabilities Cash contributions Noncontrolling Interest, Increase from Sale of Parent Equity Interest Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Income from reorganization adjustments before income taxes Income From Reorganization Adjustments Before Income Taxes Income From Reorganization Adjustments Before Income Taxes Amount Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract] Credit Concentration Risk Credit Concentration Risk [Member] Litigation Status [Axis] Litigation Status [Axis] Derivative Instrument [Axis] Derivative Instrument [Axis] Vesting [Axis] Vesting [Axis] Actual benefits paid Actual benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Fair Value of Financial Instruments and Derivatives Fair Value of Financial Instruments, Policy [Policy Text Block] Increase in deferred tax liabilities primarily due to estimated tax attribute reduction from the recognition of cancellation of debt income, partially offset by change in valuation allowance Increase In Deferred Tax Assets Due To The Recognition Of Cancellation Of Debt, Net Of Change In Valuation Allowance Increase In Deferred Tax Assets Due To The Recognition Of Cancellation Of Debt, Net Of Change In Valuation Allowance Operational and other restructuring activities Operational And Other Restructuring Charges Operational And Other Restructuring Charges Other current assets Other Assets, Current Entity [Domain] Entity [Domain] Net cash provided by (used in) investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Remaining performance obligation period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Unrealized (gains) losses on derivative instruments (Note 2) Unrealized gain (loss) on commodity derivative contracts Unrealized Gain (Loss) on Derivatives and Commodity Contracts Maximum insurance converge, non-nuclear Insurance Maximum Coverage, Property Damage Losses, Non-Nuclear Insurance Maximum Coverage, Property Damage Losses, Non-Nuclear Derivative instruments (Notes 2 and 11) Derivative asset, noncurrent Derivative instruments Derivative Asset, Noncurrent Non-cash financing activities Non-Cash Financing Activities [Abstract] Non-Cash Financing Activities Interest and other finance charges, net of capitalized interest Interest Paid, Excluding Capitalized Interest, Operating Activity Document Fiscal Year Focus Document Fiscal Year Focus Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Effective income tax rate Income tax benefit (expense) Effective Income Tax Rate Reconciliation, Percent Other Other Operating Segment [Member] Collateral received (posted), net Increase (Decrease) Cash Collateral from Counterparties Business combination, acquisition-related cost, expense Business Combination, Acquisition-Related Cost, Expense Weighted-average period of recognition (in years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Threshold Two Threshold Two [Member] Threshold Two Valuation allowance Deferred Tax Assets, Valuation Allowance Equity [Abstract] Talen Montana Talen Montana [Member] Talen Montana Unrealized gain (loss) on derivative instruments Derivatives, Policy [Policy Text Block] Segments Segment Reporting Disclosure [Text Block] 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] Plan assets fair value beginning balance Plan assets fair value ending balance Defined benefit plan assets Defined Benefit Plan, Plan Assets, Amount Stock-based compensation liabilities (Note 13) Stock-based compensation liabilities Deferred Compensation Share-Based Arrangements, Liability, Current Federal Current Federal Tax Expense (Benefit) Income tax expense Debtor Reorganization Adjustments, Income Tax Expense (Benefit) Debtor Reorganization Adjustments, Income Tax Expense (Benefit) Other Commitments [Line Items] Other Commitments [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Schedule of Net Periodic Benefit Costs Schedule of Net Benefit Costs [Table Text Block] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Amortization of nuclear fuel intangible assets Amortization of Intangible Assets Restricted cash and cash equivalents (Note 16) Restricted cash and cash equivalents Restricted cash and cash equivalents (a) Restricted Cash and Cash Equivalent, Current Other Proceeds From (Payment For) Other Items Proceeds From (Payment For) Other Items Schedule of Accumulated Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Depreciation, amortization and accretion (Note 7) Depreciation, amortization and accretion Depreciation, amortization and accretion Depreciation, Depletion and Amortization Borrowings of $470 million Under TLC Borrowings of $470 million Under TLC [Member] Borrowings of $470 million Under TLC Fuel inventory for electric generation Energy Related Inventory Professional fees Debtor Reorganization Items, Legal and Advisory Professional Fees Revolving Credit Facility Revolving Credit Facility [Member] Accounts Receivable Accounts Receivable [Policy Text Block] Write-off of debt issuance costs associated with prepetition senior secured revolving credit facility Deferred Debt Issuance Cost, Writeoff Arrangement Duration Trading Arrangement Duration Net Income (Loss) Attributable to Stockholders Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual Maximum volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Segments [Axis] Segments [Axis] Unrealized loss on qualifying derivatives Deferred Tax Assets, Derivative Instruments Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Gain (loss) on sale of assets, net (Note 17) Gain (loss) on 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Forfeited (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Postretirement Benefit Obligations Retirement Benefits [Text Block] Fair Value Fair Value Disclosures [Text Block] Other losses attributable to gain on debt discharge Debtor Reorganization Items, Other Losses Attributable To Gain On Debt Discharge Debtor Reorganization Items, Other Losses Attributable To Gain On Debt Discharge Business Acquisition [Line Items] Business Combination [Line Items] Credit Facility [Domain] Credit Facility [Domain] Derivative instruments (Notes 2 and 11) Derivative liability, current Derivative instruments Derivative Liability, Current Share repurchases Share repurchases Treasury Stock, Value, Acquired, Cost Method Postretirement benefit prior service (credits) costs, net (Note 12) Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification 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Contract, Term Reliability Backstop Auction, Baseload Capacity Contract, Term Debt Securities, Immunizing Portfolio Defined Benefit Plan, Debt Securities, Immunizing Portfolio [Member] Defined Benefit Plan, Debt Securities, Immunizing Portfolio Fair value reduction to other miscellaneous assets Fair Value Reduction to Other Miscellaneous Assets Fair Value Reduction to Other Miscellaneous Assets Debt Instrument, Redemption, Period Two Debt Instrument, Redemption, Period Two [Member] Other states State and Local Tax Jurisdiction, Other [Member] Total assets Assets, Fair Value Disclosure Unrealized gain (loss) on derivative instruments (Note 2) Unrealized Gain (Loss) On Commodity Contracts, Energy Expenses Unrealized Gain (Loss) On Commodity Contracts, Energy Expenses Energy [Axis] Energy [Axis] Enterprise value Enterprise Value Enterprise Value Related and Nonrelated Parties [Axis] Related and Nonrelated Parties [Axis] Granted (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Interest cost Interest cost Defined Benefit Plan, Interest Cost Reinstatement of liabilities subject to compromise Reinstatement Of Liabilities Subject To Compromise, Deferred Income Tax Liabilities, Net Reinstatement Of Liabilities Subject To Compromise, Deferred Income Tax Liabilities, Net Liabilities, Net Amounts Derivative Liability, Subject to Master Netting Arrangement, after Offset and Deduction Amounts recognized in accumulated other comprehensive income Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract] Restatement Determination Date: Restatement Determination Date [Axis] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Non-cash contributions Noncontrolling Interest, Increase from Subsidiary Equity Issuance Other Proceeds from (Payment for) Other Financing Activity Interest expense, debt Interest Expense, Debt Liability Business Combination, Recognized Liability Assumed, Liability [Abstract] Reclassifications from AOCI, net of tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Name Trading Arrangement, Individual Name Jointly Owned Utility Plant [Axis] Jointly Owned Utility Plant [Axis] Deferred income taxes: Deferred Income Taxes and Tax Credits [Abstract] Purchase of noncontrolling interest Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Aggregate principal amount Debt Instrument, Face Amount Statement of Comprehensive Income [Abstract] Waterford Energy Center Waterford Energy Center [Member] Waterford Energy Center Payments to acquire business, value of stock Business Combination, Consideration Transferred, Equity Interest Professional fees incurred to obtain the debtor-in-possession credit facilities Debtor Reorganization Items, Debtor-in-Possession Facility Financing Costs Noncontrolling Interest, Distribution Type [Domain] Noncontrolling Interest, Distribution Type [Domain] Noncontrolling Interest, Distribution Type [Domain] Assumptions Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Name Awards Close in Time to MNPI Disclosures, Individual Name Balance at the beginning of the period (in dollars per share) Balance at the end of the period (in dollars per share) Fair value per share (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Energy [Domain] Energy [Domain] Funding of professional fees escrow account Escrow Deposit Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Asset Acquisition [Line Items] Asset Acquisition [Line Items] Exercise of warrants Stock Issued During Period, Value, Conversion of Convertible Securities Cash Distribution To Non-Controlling Interests Cash Distribution To Non-Controlling Interests [Member] Cash Distribution To Non-Controlling Interests Equity incentive plans APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Income tax benefit (expense) Other Comprehensive Income (Loss) before Reclassifications, Tax Litigation Case [Axis] Litigation Case [Axis] Share retirements Treasury Stock, Retired, Amount Treasury Stock, Retired, Amount Auditor Firm ID Auditor Firm ID Segments [Domain] Segments [Domain] Lawrenceburg Power Plant Lawrenceburg Power Plant [Member] Lawrenceburg Power Plant Equity-Classified PSUs Equity-Classified Performance Shares [Member] Equity-Classified Performance Shares State net operating loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards, State and Local Total Debtor Reorganization Items, Liabilities Debtor Reorganization 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Accretion Expense Revenues Revenue [Policy Text Block] Liabilities, Eligible for Offset Derivative Liability, Subject to Master Netting Arrangement, Asset Offset Municipal debt securities US States and Political Subdivisions Debt Securities [Member] Payment of claims under prepetition senior secured revolving credit facility Payment Of Claims Under Prepetition Senior Secured Revolving Credit Facility Payment Of Claims Under Prepetition Senior Secured Revolving Credit Facility Gain on settlement of liabilities subject to compromise Debtor Reorganization Items, Gain On Settlement Of Liabilities Subject To Compromise Debtor Reorganization Items, Gain On Settlement Of Liabilities Subject To Compromise Fair value of liabilities assumed Business Combination, Recognized Liability Assumed, Liability All Executive Categories All Executive Categories [Member] Shares repurchased, tender offer (in shares) Treasury Stock, Shares, Acquired, Tender Offer Treasury Stock, Shares, Acquired, Tender Offer 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Shares, Employee Stock Purchase Plans And Share-Based Payment Arrangement Stock Issued During Period, Shares, Employee Stock Purchase Plans And Share-Based Payment Arrangement Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Number of suits Number Of Multi-district Litigation Bellwether Suits Number Of Multi-district Litigation Bellwether Suits Operating Revenues Business Combination, Pro Forma Information, Pro Forma Revenue Forecast Forecast [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Title of 12(b) Security Title of 12(b) Security Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Other Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table] Debt Securities, 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loss, net (Note 12) Net actuarial (gain) loss Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Payment in exchange for surrendered warrants Payment In Exchange For Surrendered Warrants Payment In Exchange For Surrendered Warrants Payment of hedge rejections Payment of hedge contract rejections Payments To Terminate Hedge Contracts, Investing Activities Payments To Terminate Hedge Contracts, Investing Activities Nuclear PTC Effective Income Tax Rate Reconciliation, Tax Credit, Energy-Related, Percent Share repurchase (in shares) Share repurchases (in shares) Treasury Stock, Shares, Acquired Award Timing Disclosures [Line Items] Environmental Matters, EPA MATS Rule Environmental Matters, EPA MATS Rule [Member] Environmental Matters, EPA MATS Rule Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Schedule of Changes in Asset Retirement Obligations Schedule of Change in Asset Retirement Obligation [Table Text Block] Schedule of Inventory Schedule of Inventory, Current [Table Text Block] Service cost Defined Benefit Plan, Service Cost Nuclear insurance, liability limit per accident Nuclear Insurance, Liability Limit Per Accident Nuclear Insurance, Liability Limit Per Accident Write-off of deferred financing cost and original issue discount Debtor Reorganization Items, Debt Issuance Cost and Debt Discount, Writeoff Debt issuances (Note 10) Proceeds from Issuance of Other Long-Term Debt Gains (losses) arising during the period, net of tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Stockholders' Equity Equity [Text Block] State Deferred State and Local Income Tax Expense (Benefit) Non-cash increase to PP&E and decrease to other current assets for contribution of Bitcoin miners to Nautilus Non-cash Increase To Property, Plant And Equipment And Decrease To Other Current Assets For Transfer Of Cryptocurrency Miners Non-cash Increase To Property, Plant And 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Issuance Costs Capitalization Of Debt Issuance Costs Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Share repurchases (Note 15) Payments for Repurchase of Common Stock Adoption Date Trading Arrangement Adoption Date Reclassifications Reclassification, Comparability Adjustment [Policy Text Block] LMBE-MC TLB payments Repayment Of Term Loan Repayment Of Term Loan TeraWulf TeraWulf [Member] TeraWulf Liabilities subject to compromise Liabilities subject to compromise Liabilities Subject to Compromise Operating Income (Loss) Operating Income (Loss) Line of Credit Line of Credit [Member] Schedule of Effect of Netting, Offsetting Liabilities Offsetting Liabilities [Table Text Block] Accumulated retained earnings (deficit) Retained Earnings (Accumulated Deficit) Nuclear decommissioning trust funds (Notes 6 and 11) NDT funds Fair Value Nuclear decommissioning trust funds Decommissioning Fund Investments, Fair Value Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Other Securities, Immunizing Portfolio Defined Benefit Plan, Other Securities, Immunizing Portfolio [Member] Defined Benefit Plan, Other Securities, Immunizing Portfolio PPL/Talen Montana Litigation PPL/Talen Montana Litigation [Member] PPL/Talen Montana Litigation Actual amount of PSUs earned by participants, percentage Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Actual Amount Of Awards Earned, Percentage Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Actual Amount Of Awards Earned, Percentage Subsequent Event Type [Domain] Subsequent Event Type [Domain] Noncontrolling Interest, Distribution Type [Axis] Noncontrolling Interest, Distribution Type [Axis] Noncontrolling Interest, Distribution Type Gain (loss) on revaluation adjustments Debtor Reorganization Items, Revaluation of Assets and Liabilities Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Other Deferred Tax Liabilities, Other Retirement Plan Type [Axis] Retirement Plan Type [Axis] Schedule of Condensed Financial Statements Condensed Financial Statements [Table Text Block] Other non-operating income (expense), net Other Nonoperating Income (Expense) Statement [Table] Statement [Table] Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Schedule of Revenues and Earnings Business Combination [Table Text Block] Deferred income taxes Deferred income taxes Deferred Income Tax Expense (Benefit) Financing Activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Fair Value Debt Instrument, Fair Value Disclosure [Abstract] Measurement Input, Risk Free Interest Rate Measurement Input, Risk Free Interest Rate [Member] Liability-Classified PSUs Liability-Classified Performance Shares [Member] Liability-Classified Performance Shares Non-Cash Distribution To Non-Controlling Interests Non-Cash Distribution To Non-Controlling Interests [Member] Non-Cash Distribution To Non-Controlling Interests Derivative option premium amortization Increase (Decrease) in Option Premium Contracts Payable Realized gain (loss) on commodity contracts Gain (Loss) on Sale of Commodity Contracts All Adjustments to Compensation All Adjustments to Compensation [Member] Share retirements (in shares) Treasury Stock, Shares, Retired Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Amendment Flag Amendment Flag Income tax benefit Share-Based Payment Arrangement, Expense, Tax Benefit Spent Nuclear Fuel Spent Nuclear Fuel [Member] Spent Nuclear Fuel Number of shares authorized (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized Other Postretirement Benefits Other Postretirement Benefits Plan [Member] Derivatives Liabilities Subject to Compromise, Derivative Liability Liabilities Subject to Compromise, Derivative Liability Equity securities, Unrealized Gains Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, Before Tax Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, Before Tax Unrealized Losses Decommissioning Fund Investments, Accumulated Gross Unrealized Loss, Before Tax Decommissioning Fund Investments, Accumulated Gross Unrealized Loss, Before Tax Total Acquired Fuel Supply Contract Liabilities, Expected Amortization, Net Acquired Fuel Supply Contract Liabilities, Expected Amortization Termination Date Trading Arrangement Termination Date Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Other liabilities, non-current, derecognized Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent Operating Revenues Business Combination, Acquiree's Revenue since Acquisition Date, Actual Weighted-Average Number of Common Shares Outstanding - Basic (in shares) Weighted-average shares outstanding - Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Net realizable value and obsolescence charges Inventory Write-down Supplemental Cash Flow Information Cash Flow, Supplemental Disclosures [Text Block] Equity-classified warrants Warrants and Rights Outstanding Schedule of Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Derivative assets Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement Issuance of member’s equity in connection with rights offering Issuance Of Members Equity In Connection With Rights Offering Issuance Of Members Equity In Connection With Rights Offering Segment Reporting [Abstract] Non-cash investing activities Noncash Investing And Operating Activities [Abstract] Noncash Investing And Operating Activities Debt Disclosure [Abstract] Asset Retirement Obligation [Line Items] Asset Retirement Obligation [Line Items] Asset Retirement Obligation [Line Items] Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Reclassifications due to settlement and (or) curtailment: Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Reclassification Adjustment, before Tax [Abstract] Scenario [Domain] Scenario [Domain] Income tax benefit (expense) Reclassification from AOCI, Current Period, Tax Available-for-sale securities unrealized gain (loss), net (Note 6) OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount TLB-2 TLB-2 Facility [Member] TLB-2 Facility Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Consolidated Entities [Axis] Consolidated Entities [Axis] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Derivative Instruments and Hedging Activities Disclosures [Line Items] Derivative Instruments and Hedging Activities Disclosures [Line Items] Termination of retail contracts Liabilities Subject to Compromise, Early Contract Termination Fees Current tax receivable Income Taxes Receivable, Current Fixed-cost monthly payments Fixed-Cost Annual Payments Fixed-Cost Annual Payments 2031-2035 Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years Use of Estimates Use of Estimates, Policy [Policy Text Block] Guarantor Obligations, Nature [Axis] Guarantor 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Securities, Available-for-Sale Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate debt securities Corporate Debt Securities [Member]