Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Long-Term Debt, Unclassified [Abstract] Long-Term Debt, Unclassified [Abstract] Trading Arrangement: Trading Arrangement [Axis] Asset Acquisition [Table] Asset Acquisition [Table] Maximum Maximum [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] Title of 12(b) Security Title of 12(b) Security Subsequent Events Subsequent Event [Member] Document Fiscal Year Focus Document Fiscal Year Focus Unsatisfied or partially unsatisfied performance obligation, period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Adjustment to Compensation, Amount Adjustment to Compensation Amount Schedule of segment EBITDA Segment Reporting, Schedule Of Reportable Segment EBITDA [Table Text Block] Tabular disclosure of information about reportable segment EBITDA. Segment Reporting [Abstract] Segment Reporting [Abstract] Taxes paid on vesting of RSUs Payment, Tax Withholding, Share-Based Payment Arrangement Total interest expense Interest expense Interest Expense, Operating and Nonoperating Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Amount accrued on settlement litigation Loss Contingency Accrual Confidentially marketed public offering Confidentially Marketed Public Offering [Member] Represents a confidentially marketed public offering. Line of Credit Line of Credit [Member] Restatement Determination Date Restatement Determination Date Inventory downward adjustment Inventory Write-down Stock issued on vesting of RSUs (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures SELF-INSURANCE Self Insurance [Line Items] Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Debt instrument, covenant, amount to maintain Debt Instrument, Covenant, Amount To Maintain Debt Instrument, Covenant, Amount To Maintain Current Current Income Tax Expense (Benefit) Amendment Flag Amendment Flag Current liabilities: Liabilities, Current [Abstract] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Payments on lease financing Finance Lease, Principal Payments Workers' compensation reserve Workers' Compensation Liability Other operating costs Other Cost of Operating Revenue Quarterly repayments percentage Quarterly Repayments Percentage To Initial Principal Amount Quarterly Repayments Percentage To Initial Principal Amount Total long-term liabilities Liabilities, Noncurrent Inventory Energy Related Inventory, Coal Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Schedule of cash, cash equivalents, and restricted cash Schedule of Cash and Cash Equivalents [Table Text Block] Property, plant and equipment: Property, Plant, and Equipment [Abstract] Entity Address, State or Province Entity Address, State or Province PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value (in USD per share) Common Stock, Par or Stated Value Per Share Asset Acquisition [Axis] Asset Acquisition [Axis] Capital Expenditures Segment Reporting, Long-Lived Asset, Expenditure for Addition Cash and Cash Equivalents [Abstract] Long-term liabilities: Liabilities, Noncurrent [Abstract] Non-vested grants - Beginning (in shares) Non-vested grants - Ending (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Basic (in shares) Weighted average shares outstanding - basic (in shares) Weighted Average Number of Shares Outstanding, Basic Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Deposited in money market Payments for Money Market Deposits The cash outflow associated with payments in deposits of money market accounts. Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current Cash payments received on future contract obligations Contract With Customer, Liability, Proceeds From Customers For Future Contractual Obligations Amount of increase in contract with customer liability due to cash received from customers as progress payments for future contractual obligations, during the reporting period. Leverage ratio Debt Instrument, Covenant, Leverage Ratio, Maximum Debt Instrument, Covenant, Leverage Ratio, Maximum allowed Entity Address, City or Town Entity Address, City or Town Asset acquisition purchase price Asset Acquisition, Consideration Transferred Awarded (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period STOCK COMPENSATION PLANS Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Accrued property taxes Taxes Payable Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Nominal capacity Electricity Generation Plant Nominal Capacity The maximum electric power generated from the assets purchased. Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] KLIM Credit Agreement KLIM Credit Agreement [Member] KLIM Credit Agreement Subsequent Event Type [Axis] Subsequent Event Type [Axis] Effect of Change in Accounting Estimate, Type [Domain] Effect of Change in Accounting Estimate, Type [Domain] Corporate — general and administrative Corporate Costs, General and Administrative The amount of general and administrative expenses related to corporate activities during the reporting period. Schedule of Long-Term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Remaining Periods Remaining Periods [Member] Remaining Periods Recent Accounting Pronouncements - Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] RSUs vesting (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Expecting to Vest, Number The number of equity-based payment instruments, excluding stock (or unit) options, that are to vest in a future period. Contract liabilities Increase (Decrease) in Contract with Customer, Liability Schedule of key metrics reviewed by CODM Segment Reporting [Table Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Amortization of debt issuance costs Amortization of debt issuance costs Amortization of Debt Issuance Costs Corporate and Other and Eliminations Corporate and Other and Eliminations Eliminations and Reconciling Items [Member] Represents the aggregate total of reconciling items and elimination items. B. Riley Securities, Inc. B. Riley Securities, Inc. [Member] Represents B. Riley Securities Inc. Related and Nonrelated Parties [Axis] Related and Nonrelated Parties [Axis] Schedule of Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Net debt Net debt Long-Term Debt Document Period End Date Document Period End Date Change in current assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Net cash used in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Seller And Third Party Vendors Seller And Third Party Vendors [Member] Seller And Third Party Vendors Principal amount of debt instrument Debt Instrument, Face Amount Basic earnings per common share: Earnings Per Share, Basic [Abstract] AT MARKET AGREEMENT AND CONFIDENTIALLY MARKETED PUBLIC OFFERING Equity [Text Block] EXPENSES: Costs and Expenses [Abstract] Security Exchange Name Security Exchange Name Schedule of reconciliation of segment revenues to consolidated Segment Reporting, Reconciliation of Revenue by Segment to Consolidated [Table Text Block] Interest rate, effective percentage Debt Instrument, Interest Rate, Effective Percentage SELF-INSURANCE Insurance Disclosure [Text Block] Coal sales Coal sales Coal Sales [Member] Represents coal sales. Net income (loss) - diluted Net Income (Loss) Attributable to Parent, Diluted Average zonal resource credits, annual Long-Term Purchase Commitment, Average Zonal Resource Credits, Annual Long-Term Purchase Commitment, Average Zonal Resource Credits, Annual Entity Shell Company Entity Shell Company Consolidation Items [Domain] Consolidation Items [Domain] Operating lease liability - current portion Operating Lease, Liability, Current BASIS OF PRESENTATION General Business [Line Items] Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] Finance lease right-of-use assets Finance Lease, Right-of-Use Asset, after Accumulated Amortization Oaktown Gas, LLC Oaktown Gas, LLC [Member] Represents Oaktown Gas, LLC. NET INCOME (LOSS) PER SHARE Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name NET INCOME (LOSS) PER SHARE: Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Debt, net Secured Long-Term Debt, Noncurrent Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Accounts receivable Increase (Decrease) in Accounts and Notes Receivable Total liabilities Liabilities Trading Symbol Trading Symbol Geographical [Domain] Geographical [Domain] Schedule of interest expense Interest Income and Interest Expense Disclosure [Table Text Block] Capital expenditures Payments to Acquire Property, Plant, and Equipment 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] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Merom power plant - megawatt capacity Merom Power Plant, Electricity Generation Capacity The mega-watt capacity of the Merom power plant operated by the entity. Company Selected Measure Name Company Selected Measure Name Sale of Stock [Domain] Sale of Stock [Domain] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Fees paid to lenders Debt Related Commitment Fees and Debt Issuance Costs FAIR VALUE MEASUREMENTS Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Diluted earnings per common share: Earnings Per Share, Diluted [Abstract] SUPPLEMENTAL NON-CASH FLOW INFORMATION: Noncash Investing and Financing Items [Abstract] Total debt Total debt Long-Term Debt, Gross Payments on debt Repayments of Bank Debt Extension fee Line of Credit Facility, Commitment Fee Percentage Credit Facility [Domain] Credit Facility [Domain] CASH FLOWS FROM OPERATING ACTIVITIES: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Compensation Amount Outstanding Recovery Compensation Amount Amortization of contract liabilities Capitalized Contract Cost, Amortization Individual: Individual [Axis] Diluted (in shares) Weighted average shares outstanding - diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted REVENUE Disaggregation of Revenue [Line Items] Physically Delivered Prepaid Power Contract Physically Delivered Prepaid Power Contract [Member] Represents a physically delivered prepaid power contract of the entity. Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Debt Instrument, Covenant [Axis] Debt Instrument, Covenant [Axis] Debt Instrument, Covenant Segment EBITDA Total Segment EBITDA Segment EBITDA Earnings Before Interest, Tax, Depreciation And Amortization The amount of earnings before interest, tax, depreciation and amortization attributable to the entity during the reporting period. Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Award Timing Predetermined Award Timing Predetermined [Flag] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Effective income tax rate reconciliation, percent Effective Income Tax Rate Reconciliation, Percent Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Electric sales Electric Sales [Member] Represents electric sales. ATM At Market Offering [Member] Represents the share offering classified as ATM (At-the-market). Add: Dilutive effects of Restricted Stock Units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Revision of prior period error correction adjustment Revision of Prior Period, Error Correction, Adjustment [Member] All Executive Categories All Executive Categories [Member] Long term supply commitment, contract term Long Term Supply Commitment, Contract Term Period covered by long-term supply commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Prepaid contract Long Term Supply Agreement, Prepaid Contract, Amount The prepaid amount received for the long-term supply agreement. Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Preferred stock, par value (in USD per share) Preferred Stock, Par or Stated Value Per Share Vesting [Domain] Vesting [Domain] Scenario [Domain] Scenario [Domain] Asset Acquisition [Domain] Asset Acquisition [Domain] CASH, CASH EQUIVALENTS, AND RESTRICTED CASH: Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation [Abstract] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Schedule of earnings (loss) per share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] SEGMENTS OF BUSINESS Segment Reporting [Text Block] Minimum Minimum [Member] Expiration Date Trading Arrangement Expiration Date WEIGHTED AVERAGE SHARES OUTSTANDING Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] 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] Third-Party Nonrelated Party [Member] Buildings and equipment Buildings And Equipment Amount before accumulated depreciation of building structures held for productive use and tangible personal property used to produce goods and services. Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] ATM offering Proceeds from Issuance of Common Stock Common stock, shares authorized (in shares) Common Stock, Shares Authorized Schedule of Non-vested RSU vesting years Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Exercise Price Award Exercise Price Stock issued on vesting of RSUs Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures CASH FLOWS FROM INVESTING ACTIVITIES: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] EQUITY METHOD INVESTMENTS Schedule of Equity Method Investments [Line Items] SEGMENTS OF BUSINESS Segment Reporting [Line Items] Document Quarterly Report Document Quarterly Report Period Long-Term Purchase Commitment, Period Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Segments [Domain] Segments [Domain] Cash, cash equivalents, and restricted cash, beginning of period Cash, cash equivalents, and restricted cash, end of period Total cash and cash equivalents and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Schedule of segment assets and capital expenditures Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Long-Lived Asset [Table Text Block] DEBT Debt Disclosure [Text Block] Scenario [Axis] Scenario [Axis] Repayments of long-term debt Repayments of Long-Term Debt Restricted Cash and Cash Equivalents [Axis] Restricted Cash and Cash Equivalents [Axis] Debt issuance costs, net Less total unamortized debt issuance cost Debt Issuance Costs, Net Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Equity method investments Equity Method Investments Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Secured Debt Secured Debt [Member] Proceeds from offering, net of issuance costs Net proceeds of common stock under ATM Program Sale of Stock, Consideration Received on Transaction Total operating expenses Costs and Expenses Adoption Date Trading Arrangement Adoption Date Liquidity Total Liquidity The amount of liquidity under the debt instrument. Investment in equity method investments Payments to Acquire Equity Method Investments Counterparty Name [Domain] Counterparty Name [Domain] Total variable costs Variable Costs, Total The amount of total variable costs incurred by the entity during the reporting period. Total stockholders’ equity Balance at the beginning Balance at the end Equity, Attributable to Parent Scenario, Plan Scenario, Plan [Member] Excess of judgements Debt Instrument, Covenant, Excess Of Judgements Debt Instrument, Covenant, Excess Of Judgements Stock-based compensation APIC, Share-Based Payment Arrangement, Option, Increase for Cost Recognition ASSETS Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Workers' compensation reserve Workers' Compensation Liability, Current Debt instrument, fee amount Debt Instrument, Fee Amount Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Offering expenses Payments of Stock Issuance Costs Insider Trading Policies and Procedures [Line Items] Other revenues Other operating revenue Other Operating Income Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Deferred Deferred income tax Deferred Income Tax Expense (Benefit) General and administrative Selling, General and Administrative Expense Number of purchase agreements, entered into Long-Term Purchase Commitment, Number Of Purchase Agreements, Entered Into Long-Term Purchase Commitment, Number Of Purchase Agreements, Entered Into Letter of credit Letter of Credit [Member] SEGMENTS OF BUSINESS Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items] Group health insurance Accrued Employee Benefits COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Construction work in progress Construction in Progress, Gross Antidilutive securities excluded from computation of earnings per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Number of segments Number of Operating Segments Restricted stock units Restricted Stock Units (RSUs) [Member] Accrued payroll Accrued Payroll Taxes Entity Central Index Key Entity Central Index Key Common stock, $.01 par value, 100,000 shares authorized; 47,147 and 43,817 issued and outstanding, as of September 30, 2026 and December 31, 2025, respectively Common Stock, Value, Outstanding Less - accumulated depreciation, depletion and amortization Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization All Adjustments to Compensation All Adjustments to Compensation [Member] 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] Net cash (used in) provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Payments for settlement in escrow Payments for Legal Settlements Cash paid on asset retirement obligation reclamation Asset Retirement Obligation, Cash Paid to Settle Merom power plant - number of units Merom Power Plant, Number Of Units The number of units of the Merom power plant operated by the entity. 2026 Long-Term Debt, Maturity, Remainder of Fiscal Year Income Statement [Abstract] Income Statement [Abstract] Stockholders' equity: Equity, Attributable to Parent [Abstract] Document Transition Report Document Transition Report Investment, Name [Axis] Investment, Name [Axis] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Less: capitalized interest Less: capitalized interest Interest Costs Capitalized Adjustment Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate City Area Code City Area Code Variable Rate [Domain] Variable Rate [Domain] Consolidated excess cash flow, percentage Consolidated Excess Cash Flow, Percentage Consolidated Excess Cash Flow, Percentage All Individuals All Individuals [Member] Amortization of right-of-use assets Operating Lease, Right-of-Use Asset, Periodic Reduction Schedule of revenue by geographic area Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue [Table Text Block] Name Forgone Recovery, Individual Name Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Shares outstanding (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Statement Statement [Line Items] Total assets Assets Assets Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Accounting Standards Update and Change in Accounting Principle [Abstract] Accounting Standards Update and Change in Accounting Principle [Abstract] Operating Segment Operating Segments [Member] Interest expense Interest expense included in the condensed consolidated statements of operations Interest Expense, Nonoperating STOCK COMPENSATION PLANS Share-Based Payment Arrangement [Text Block] Stock issued in offering, net of issuance costs (in shares) Stock Issued During Period, Shares, New Issues PEO PEO [Member] 2028 Long-Term Debt, Maturity, Year Two Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Self-insurance liabilities Self Insurance Reserve Prepaid expenses Increase (Decrease) in Prepaid Expense Stock-based compensation expense Share-Based Payment Arrangement, Expense Other Other Liabilities, Noncurrent Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Revenue recognized, cash payment received in prior period Contract with Customer, Liability, Revenue Recognized Subsequent Event Type [Domain] Subsequent Event Type [Domain] Retained Deficit Retained Earnings [Member] Revolving credit Revolving Credit Facility [Member] Revision of Prior Period [Domain] Revision of Prior Period [Domain] Delivered energy (including contract liability amortization) Delivered energy revenue Delivered Energy [Member] Represents delivered energy. AT MARKET AGREEMENT ("ATM") AND CONFIDENTIALLY MARKETED PUBLIC OFFERING ("CMPO") AT MARKET AGREEMENT ("ATM") AND CONFIDENTIALLY MARKETED PUBLIC OFFERING ("CMPO") [Abstract] No definition available. Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Debt issuance costs Payments of Debt Issuance Costs Diluted (in USD per share) Diluted net income (loss) per share (in USD per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net cash (used in) provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Taxes paid on vesting of RSUs Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Non-cash change in capital expenditures included in accounts payable and prepaid expense Change In Capital Expenditures Included In Accounts Payable And Prepaid Expense Change In Capital Expenditures Included In Accounts Payable And Prepaid Expense Repayment of TCB Credit Facility directly by lenders from KLIM proceeds Debt Refinanced, Noncash Debt Refinanced, Noncash Remaining purchase price Asset Acquisition, Remaining Purchase Price Asset Acquisition, Remaining Purchase Price Proceeds from long-term lines of credit Proceeds from Long-Term Lines of Credit Other operating and maintenance costs Other operating and maintenance costs Utilities Operating Expense, Maintenance and Operations Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] 2029 Long-Term Debt, Maturity, Year Three Intercompany Loan Intercompany Loan [Member] Intercompany Loan Seller Escrow Seller Escrow [Member] Seller Escrow Borrowings of debt Proceeds from Bank Debt Share-Based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] CASH FLOWS FROM FINANCING ACTIVITIES: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Total Sales Operating Revenues Revenue from Contract with Customer, Excluding Assessed Tax Total property, plant and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Price per share Shares Issued, Price Per Share Utilities Utilities Direct Communications and Utilities Costs Number of generating units Long-Term Purchase Commitment, Number Of Generating Units Long-Term Purchase Commitment, Number Of Generating Units SELF-INSURANCE SELF-INSURANCE [Abstract] N/A Schedule of revenue by major customers Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Customer, Extent of Reliance [Table Text Block] Excess of net proceeds of certain asset dispositions and casualty events Excess Of Net Proceeds From Certain Asset Dispositions And Causality Events, Amount Excess Of Net Proceeds From Certain Asset Dispositions And Causality Events, Amount Construction Account Construction Account [Member] Construction Account INVENTORY Inventory Disclosure [Text Block] Coal Operations Coal Operations Coal Operations [Member] Represents coal operations Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Electric Operations Electric Operations Electric Operations [Member] Represents electric operations. REVENUE Revenue from Contract with Customer [Text Block] Stock issued in offering, net of issuance costs Stock Issued During Period, Value, New Issues Intercompany loan Debt Instrument, Covenant, Loan Debt Instrument, Covenant, Loan Prepaid expenses Prepaid Expense, Current Accretion on contract liabilities Contract with Customer, Liability, Accretion Amount of increase through recognition of expense for the passage of time, typically for liabilities, that have been discounted to their net present values attributable to contract with customer liabilities for the reporting period. Inventory Increase (Decrease) in Inventories Segment Reporting [Table] Segment Reporting [Table] Number of shares available for grants (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant INCOME TAX EXPENSE (BENEFIT): Income Tax Expense (Benefit), Continuing Operations [Abstract] Schedule of maturities of long-term debt Schedule of Maturities of Long-Term Debt [Table Text Block] Equity Method Investment [Table] Equity Method Investment [Table] Sale of Stock [Axis] Sale of Stock [Axis] ACCRUED LIABILITIES AND OTHER Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] Other Restricted Cash Other Restricted Cash [Member] Other Restricted Cash Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] INCOME (LOSS) FROM OPERATIONS Operating Income (Loss) Delayed Draw Term Loan Delayed Draw Term Loan (DDTL) [Member] Revenue expected to be recognized Revenue, Remaining Performance Obligation, Amount Current Fiscal Year End Date Current Fiscal Year End Date Debt Instrument, Covenant [Domain] Debt Instrument, Covenant [Domain] Debt Instrument, Covenant [Domain] Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount 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] Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Common stock, shares issued (in shares) Balance at the beginning (in shares) Balance at the end (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] EQUITY METHOD INVESTMENTS Equity Method Investments and Joint Ventures Disclosure [Text Block] Asset retirement obligations Asset Retirement Obligations, Noncurrent Reimbursement Debt Instrument, Covenant, Reimbursement Debt Instrument, Covenant, Reimbursement Debt Instrument, repaid, principal Debt Instrument, Repaid, Principal Equity Components [Axis] Equity Components [Axis] Intercompany Related Party [Member] Product and Service [Domain] Product and Service [Domain] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Variable Rate [Axis] Variable Rate [Axis] Current portion of lease financing Finance Lease, Liability, Current Deferred income taxes Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Average base energy, annual Long-Term Purchase Commitment, Average Base Energy, Annual Long-Term Purchase Commitment, Average Base Energy, Annual Entity Small Business Entity Small Business Termination Date Trading Arrangement Termination Date Taxes paid on vesting of RSUs (in shares) Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Excess of other indebtedness Debt Instrument, Covenant, Excess Of Other Indebtedness Debt Instrument, Covenant, Excess Of Other Indebtedness Other noncurrent assets Other Assets, Noncurrent Document Type Document Type Loss on extinguishment of debt Loss on extinguishment of debt Gain (Loss) on Extinguishment of Debt Gain (Loss) on Extinguishment of Debt Fair Value as of Grant Date Award Grant Date Fair Value PIK interest Paid-in-Kind Interest Debt instrument, redemption price, percentage Debt Instrument, Redemption Price, Percentage Paid-in-kind interest rate Investment, Interest Rate, Paid in Kind Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Contract liabilities - long-term Contract with Customer, Liability, Noncurrent Accredited capacity Accredited capacity revenue Accredited Energy Capacity [Member] Represents accredited capacity revenue. Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name NET INCOME (LOSS) BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Other interest Interest Expense, Other Commitments and contingencies (Note 15) Commitments and Contingencies First Tested Period First Tested Period [Member] First Tested Period Total sales and operating revenues Revenues Total property, plant and equipment Property, Plant, and Equipment, before Accumulated Depreciation, Depletion, and Amortization Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Equity method investment (loss) Equity method investment loss Income (Loss) from Equity Method Investments Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Parts and supplies Inventory, Supplies, Net of Reserves Counterparty Name [Axis] Counterparty Name [Axis] LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] All Award Types Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Parts and supplies Increase (Decrease) in Materials and Supplies SUPPLEMENTAL CASH FLOW INFORMATION: Supplemental Cash Flow Information [Abstract] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] PEO Name PEO Name Geographical [Axis] Geographical [Axis] Accrued liabilities and other Total accrued liabilities and other Accrued Liabilities and Other Liabilities Restricted Cash Restricted Cash Total contract liabilities - beginning balance Total contract liabilities - ending balance Contract with Customer, Liability Cost of purchased power Cost of purchased power Cost of Purchased Power Amount of costs incurred for purchase of power that are directly related to goods produced and sold and services rendered during the reporting period. Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number 2028 Represents Vesting in 2028 [Member] The RSU's vesting in 2028. Interest expense, debt Interest Expense, Debt Cash, Cash Equivalents and Restricted Cash Total cash and cash equivalent and restricted cash balances on deposit with financial institutions Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Letter Of Credit Collateral Letter Of Credit Collateral [Member] Letter Of Credit Collateral Seller Seller [Member] Seller AT MARKET AGREEMENT ("ATM") AND CONFIDENTIALLY MARKETED PUBLIC OFFERING ("CMPO") Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Other Other Accrued Liabilities, Current Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Base rate Base Rate [Member] Contract with Customer, Liability [Roll Forward] Contract with Customer, Liability [Roll Forward] Contract with Customer, Liability Mine development Mine Development, Gross Amount before accumulated depreciation of costs for developing new mines and expanding the capacity of existing mines. Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Land and mineral rights Mineral Rights Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Restricted cash Restricted Cash and Cash Equivalent, Current 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] BASIS OF PRESENTATION Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Debt Instrument [Axis] Debt Instrument [Axis] Percentage of equity method investment Equity Method Investment, Ownership Percentage Stock-based compensation Share-Based Payment Arrangement, Noncash Expense Service Life Service Life [Member] Interest Expense: Interest Expense, Operating and Nonoperating [Abstract] PIK interest Paid-In-Kind Interest, Non-Cash Paid-In-Kind Interest, Non-Cash Labor Labor Labor and Related Expense Schedule of debt Schedule of Debt [Table Text Block] Third party other customers Other Third Party Indiana Customers [Member] Represents other customers. Investment, Name [Domain] Investment, Name [Domain] 2027 Long-Term Debt, Maturity, Year One Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Basic (in USD per share) Basic earnings (loss) per common share (in USD per share) Earnings Per Share, Basic Schedule of Non-vested activity table Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block] Contract liabilities - current Contract with Customer, Liability, Current Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] Award Type Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accounts receivable Accounts receivable from contracts with customers - beginning balance Accounts receivable from contracts with customers - ending balance Accounts Receivable, after Allowance for Credit Loss, Current Retained deficit Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] 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] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Issued Common Stock [Member] (Gain) loss on disposal or abandonment of assets, net Loss (gain) on disposal or abandonment of assets, net Gain (loss) on disposal or abandonment of assets, net Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Effect of Change in Accounting Estimate, Type [Axis] Effect of Change in Accounting Estimate, Type [Axis] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Reclassifications Reclassification, Comparability Adjustment [Policy Text Block] Line of credit facility, accordion feature, increase limit Line of Credit Facility, Accordion Feature, Increase Limit Line of Credit Facility, Accordion Feature, Increase Limit Revenue recognized, cash payment received in current period Revenue Recognized from Current Period Increase in Contract Liability Amount of revenue recognized that was from current period increase in the balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. Interest on debt Cash interest Interest Expense, Debt, Excluding Amortization Equity Awards Adjustments Equity Awards Adjustments [Member] Credit Agreement Credit Agreement [Member] Represents the credit agreement. REVENUE Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Asset Acquisition [Line Items] Asset Acquisition [Line Items] Total liabilities and stockholders’ equity Liabilities and Equity Employee Stock Option Share-Based Payment Arrangement, Option [Member] Debt service coverage ratio Debt Instrument Covenant, Debt Service Coverage Ratio Debt Instrument Covenant, Debt Service Coverage Ratio Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Table] Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Table] ARO - current portion Asset Retirement Obligation, Current Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Proceeds from sale of equipment Proceeds from Sale of Machinery and Equipment Inventory Disclosure [Abstract] Inventory Disclosure [Abstract] Tabular List, Table Tabular List [Table Text Block] Vesting [Axis] Vesting [Axis] Additional paid-in capital Additional Paid in Capital All other Other Nonoperating Income (Expense) Asset retirement obligations accretion ARO accretion Asset Retirement Obligation, Accretion Expense Name Awards Close in Time to MNPI Disclosures, Individual Name 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] Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period General and administrative General and Administrative Expense Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Accrued Liabilities and Other Liabilities [Abstract] Accrued Liabilities and Other Liabilities [Abstract] Preferred stock, $.10 par value, 10,000 shares authorized; none issued Preferred Stock, Value, Issued Segment margin without general and administrative Margin Before General And Administrative Expense The amount of margin earned by the entity before deduction for general and administrative costs during the reporting period. Change in Accounting Estimate Change In Accounting Estimate [Policy Text Block] Disclosure of accounting policy for the change in accounting estimates in the preparation of financial statements in conformity with generally accepted accounting principles. Adjustment to Compensation: Adjustment to Compensation [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Asset acquisition payment Payments to Acquire Productive Assets Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] GENERAL BUSINESS [Table] GENERAL BUSINESS [Table] Disclosure for the general note to the financial statements for the reporting entity for the nature of business. Master Power Purchase and Sale Agreement Master Power Purchase and Sale Agreement [Member] Represents information pertaining to Master Power Purchase and Sale Agreement. Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Exploration costs Exploration costs Exploration Expense Maximum liability per workers' compensation claim Maximum Liability Per Workers' Compensation Claim Maximum Liability Per Workers' Compensation Claim Inventory adjustments Inventory Adjustments Third party Indiana customers INDIANA Name Measure Name INCOME TAXES Income Tax Disclosure [Text Block] Cash and Cash Equivalent [Table] Cash and Cash Equivalent [Table] Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Other Other Noncash Income (Expense) BANK DEBT Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] New Credit Facility New Credit Facility [Member] Represents the new credit facility. Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Maximum annual liability for workers' compensation claims Maximum Annual Liability For Workers' Compensation Claims Maximum Annual Liability For Workers' Compensation Claims Accrued liabilities Accrued Liabilities Revision of Prior Period [Axis] Revision of Prior Period [Axis] Name Trading Arrangement, Individual Name Unrecognized stock compensation expense Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Cash and cash equivalents Cash and Cash Equivalent Debt instrument, interest rate during period Debt Instrument, Interest Rate During Period Aggregate gross proceeds Equity Sales Agreement Maximum Aggregate Gross Proceeds Represents the maximum aggregate gross proceeds relating to the equity sales agreement. 2029 Represents Vesting in 2029 [Member] Represents information pertaining to vesting in 2029. Future workers' compensation claim payments Future Workers' Compensation Claim Payments [Member] Represents future workers' compensation claim payments Company Selected Measure Amount Company Selected Measure Amount Schedule of EBITDA Margin to Income (loss) before Income Taxes Segment Reporting, Reconciliation of Profit (Loss) by Segment to Consolidated [Table Text Block] Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Depreciation, depletion and amortization Depreciation, depletion and amortization Depreciation, Depletion and Amortization SOFR rate Secured Overnight Financing Rate (SOFR) [Member] RESTRICTED CASH Cash and Cash Equivalents Disclosure [Text Block] 2026 Represents Vesting in 2026 [Member] Represents vesting in 2026. Current assets: Assets, Current [Abstract] Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Right-of-use asset additions Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Total income tax expense (benefit) Income Tax Expense (Benefit) Period of sale agreement Atm Offering Notice for Termination The number of days/weeks/months/years of notice required to terminate an ATM offering. Award Timing Method Award Timing Method [Text Block] Basis of consolidation Consolidation, Policy [Policy Text Block] Increase in cash, cash equivalents, and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Accretion on contract liabilities Accretion Expense RECENT ACCOUNTING PRONOUNCEMENTS Accounting Standards Update and Change in Accounting Principle [Text Block] Fuel Fuel Fuel Costs NET INCOME (LOSS) Net income (loss) Net income (loss) - basic Net Income (Loss) Attributable to Parent Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Unamortized bank fees Unamortized Debt Issuance Expense 2027 Represents Vesting in 2027 [Member] The RSU's vesting in 2027. Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Schedule of remaining performance obligation disaggregated by segment and contract duration Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Interest income Investment Income, Interest Litigation settlement amount Litigation Settlement, Amount Awarded to Other Party Sunrise Energy, LLC Sunrise Energy, LLC [Member] Represents Sunrise Energy, LLC. Schedule of beginning and ending accounts receivable and contract liabilities Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Asset acquisition additional cost Asset Acquisition, Consideration Transferred, Transaction Cost Self Insurance [Table] Self Insurance [Table] Disclosure for the general note to the financial statements for the self-insurance taken by the entity. SALES AND OPERATING REVENUES: Revenues [Abstract] Acquisition of Turbine Equipment Acquisition Of Turbine Equipment [Member] Represents acquisition of turbine equipment. Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]