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Document Quarterly Report Document Quarterly Report 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] Trade receivables Accounts Receivable, after Allowance for Credit Loss Number of mines Business Combination, Number Of Mines Business Combination, Number Of Mines Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Business Combination [Table] Business Combination [Table] Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Investments in DTA Payments to Acquire Projects Costs and Expenses Costs and Expenses Adoption Date Trading Arrangement Adoption Date Metallurgical Metallurgical Segment [Member] Represents CONSOL Marine Terminal. 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Postretirement Benefits Other Than Pensions Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Postretirement Benefits Other Than Pensions Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Postretirement Benefits Other Than Pensions Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Debt instrument, covenant, fixed charge coverage ratio, actual Debt Instrument Covenant Fixed Charge Coverage Ratio Actual Represents actual fixed charge coverage ratio for debt instrument covenant. 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Measurement Basis [Axis] Measurement Basis [Axis] Repurchases of Common Stock (in shares) Repurchased and retired (in shares) Stock Repurchased and Retired During Period, Shares Other Revenue Other Revenue [Member] Other Revenue Other Noncurrent Liabilities Other Liabilities, Noncurrent Retirement Plan Type [Axis] Retirement Plan Type [Axis] Inventories Business Combination, Recognized Asset Acquired, Inventory, Current Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Accounts Payable Business Combination, Recognized Liability Assumed, Accounts Payable, Current Leer South Mine Leer South Mine [Member] Leer South Mine Subsequent Event Type [Domain] Subsequent Event Type [Domain] Retained Earnings Retained Earnings [Member] Revolving Credit Facility Revolving Credit Facility [Member] Cash and Cash Equivalents Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Business Interruption Loss [Domain] Business Interruption Loss [Domain] 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] Diluted Earnings (Loss) per Share (in dollars per share) Diluted (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net Cash Used in Financing Activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Shares Withheld for Taxes Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Liability for below market lease acquired Business Combination, Recognized Liability Assumed, Below Market Lease, Gross, Noncurrent Business Combination, Recognized Liability Assumed, Below Market Lease, Gross, Noncurrent Litigation Case [Domain] Litigation Case [Domain] Amortization expenses Intangible Asset, Finite-Lived, Amortization Expense Schedule of Pro Forma Adjustments Business Combination, Pro Forma Information [Table Text Block] Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Total Assets Acquired Business Combination, Recognized Asset Acquired, Asset Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Business Combination, Pro Forma Information, Nonrecurring Adjustment [Domain] Business Combination, Pro Forma Information, Nonrecurring Adjustment [Domain] Cash Flows from Financing Activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Revenues Total Revenue from Contracts with Customers Revenue from Contract with Customer, Excluding Assessed Tax Unused borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Fee on unused commitments percentage Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Interest Cost Defined Benefit Plan, Interest Cost Third-Party Terminal Revenue Terminal Revenue [Member] Represents information related to terminal revenue. Financial Instruments [Domain] Financial Instruments [Domain] Surety Bonds: Surety Bond [Member] Expected amortization rate in 2029 Finite-Lived Intangible Asset, Expected Amortization Rate, Year Three Finite-Lived Intangible Asset, Expected Amortization Rate, Year Three Commodity Derivatives Derivative Asset Inventories Inventory Disclosure [Text Block] Total Workers’ Compensation Expense Defined Benefit Plan, Workers Compensation Expense Defined Benefit Plan, Workers Compensation Expense Intangible Asset, Finite-Lived, Class [Axis] Intangible Asset, Finite-Lived, Class [Axis] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Purchases of Short-Term Investments Payments to Acquire Short-Term Investments Fair Value Estimate of Fair Value Measurement [Member] Revenue from Contracts with Customers Revenue from Contract with Customer [Text Block] Issuance of Common Stock Stock Issued During Period, Value, New Issues Revolving Credit Facility and TLA Facility Revolving Credit Facility and TLA Facility [Member] Represents information related to revolving credit facility and TLA facility. Other Operating Liabilities Increase (Decrease) in Other Current Liabilities Other Receivables, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Receivables, Net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other Receivables, Net Other Investing Activity Payment for (Proceeds from) Other Investing Activity Inventories Increase (Decrease) in Inventories Segment Reporting [Table] Segment Reporting [Table] Other Accrued Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Accrued Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Accrued Liabilities Equity Issued as Consideration for Merger Equity Issued as Consideration for Merger Equity Issued as Consideration for Merger Other Current Assets Other Assets, Current Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Net gains on changes in fair value Derivative, Gain (Loss) on Derivative, Net Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Income (Loss) from Operations Operating Income (Loss) Outstanding performance obligation, amount Revenue, Remaining Performance Obligation, Amount Current Fiscal Year End Date Current Fiscal Year End Date Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Derivative [Line Items] Derivative [Line Items] Merger with Arch Business Combination [Text Block] Debt instrument, covenant, first lien gross leverage ratio Debt Instrument Covenant First Lien Gross Leverage Ratio Represents first lien gross leverage ratio for debt instrument covenant. 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] Dividends Declared per Common Share (in dollars per share) Dividends on Common Shares (in dollars per share) Dividends announced (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity File Number Entity File Number Pneumoconiosis Benefits Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Pneumoconiosis Benefits Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Pneumoconiosis Benefits Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Service Cost Defined Benefit Plan, Service Cost Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Common stock, shares issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] Schedule of Guarantor Obligations Schedule of Guarantor Obligations [Table Text Block] Asset Retirement Obligations Asset Retirement Obligations, Noncurrent Cost of Sales (exclusive of items shown separately below) Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization Equity Components [Axis] Equity Components [Axis] Product and Service [Domain] Product and Service [Domain] Closed and Idle Mine Costs Closed and Idle Mine Costs Closed and Idle Mine Costs Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Deferred Income Taxes Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Small Business Entity Small Business Comprehensive Income (Loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Debt instrument, covenant, net leverage ratio, maximum Debt Instrument Covenant Net Leverage Ratio Maximum Represents maximum net leverage ratio for debt instrument covenant. Accounts Receivable Securitization Accounts Receivable Securitization [Text Block] Entire disclosure of accounts receivable securitization. Termination Date Trading Arrangement Termination Date Property, Plant, and Equipment [Line Items] Property, Plant, and Equipment [Line Items] Subsequent Events [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Short-Term Investments Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Short-Term Investments Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Short-Term Investments Statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Actuarially Determined Long-Term Liability Adjustments (Net of Tax: ($191), ($109), ($573), ($327)) Actuarially Determined Long-Term Liability Adjustments Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Expected amortization rate in 2026 Finite-Lived Intangible Asset, Expected Amortization Rate, Remainder of Fiscal Year Finite-Lived Intangible Asset, Expected Amortization Rate, Remainder of Fiscal Year Total Other Assets Other Assets, Noncurrent Document Type Document Type 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] Net fair value of derivatives included in Other Current Assets Derivative Asset, Current Number of export terminals with ownership interest Number Of Export Terminals, Ownership Interests Number Of Export Terminals, Ownership Interests Other Accrued Liabilities Total Other Accrued Liabilities Accrued Liabilities, Current Loss on Debt Extinguishment Loss on Debt Extinguishment Loss on extinguishment of debt Gain (Loss) on Extinguishment of Debt Fair Value as of Grant Date Award Grant Date Fair Value Debt instrument, covenant, first lien gross leverage ratio, actual Debt Instrument Covenant First Lien Gross Leverage Ratio Actual Represents the actual first lien gross leverage ratio for debt instrument covenant. Allowance for Credit Losses Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest Gain on Sale of Assets Gain (Loss) on Disposition of Assets Workers' Compensation Workers Compensation [Member] Represents information related to workers compensation. Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Arrangement Duration Trading Arrangement Duration Subsequent Event [Line Items] Subsequent Event [Line Items] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Proceeds from Long-Term Debt Issuance Proceeds from Issuance of Long-Term Debt Local Phone Number Local Phone Number Other Postretirement Benefits Other Postretirement Benefits Plan [Member] Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name CWP Coal Workers Pneumoconiosis [Member] Represents information related to coal workers pneumoconiosis. WVEDA Solid Waste Disposal Facility Revenue Bonds at 5.45% WVEDA Solid Waste Disposal Revenue Bonds [Member] WVEDA Solid Waste Disposal Revenue Bonds (Loss) Earnings Before Income Tax 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] Commitments and Contingent Liabilities (Note 14) Commitments and Contingencies Funds for Asset Retirement Obligations Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Funds For Asset Retirement Obligations Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Funds For Asset Retirement Obligations Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Loss from Equity Method Investments Income (Loss) from Equity Method Investments Other Assets: Other Assets [Abstract] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Amortization expense for assets under finance lease Finance Lease, Right-of-Use Asset, Amortization Receivable Type [Axis] Receivable Type [Axis] Changes in Operating Liabilities: Increase (Decrease) in Operating Liabilities [Abstract] Supplies Inventory, Supplies, Net of Reserves Other Profit or Loss Reconciliation Of Segment Information, Other Profit (Loss) Reconciliation Of Segment Information, Other Profit (Loss) LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Inventories Total Inventories Inventory, Net All Award Types Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] Mine Development Mine Development [Member] Workers’ Compensation Workers' Compensation Liability, Noncurrent Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Identified intangible assets amortized, contract term Business Combination, Identified Intangible Assets Amortized, Contract Term Business Combination, Identified Intangible Assets Amortized, Contract Term PEO Name PEO Name Geographical [Axis] Geographical [Axis] Other Segment Items Segment Reporting, Other Segment Item, Amount Long-Lived Asset, Class [Axis] Long-Lived Asset, Class [Axis] Retirement Plan Name [Domain] Retirement Plan Name [Domain] Net Cash and Restricted Cash Acquired from Merger Cash Acquired from Acquisition Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Accounts Receivable, Allowance for Credit Loss [Roll Forward] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Assets Acquired: Business Combination, Recognized Asset Acquired, Asset [Abstract] Cash, Cash Equivalents and Restricted Cash at Beginning of Period Cash, Cash Equivalents and Restricted Cash at End of Period Cash, Cash Equivalents and Restricted Cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Metallurgical Metallurgical [Member] Metallurgical Accounts Payable Increase (Decrease) in Accounts Payable Other Other Accrued Liabilities, Current Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Business Interruption Loss [Axis] Business Interruption Loss [Axis] Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] 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] Debt Instrument [Axis] Debt Instrument [Axis] Subsequent Event [Table] Subsequent Event [Table] Other Noncurrent Liabilities Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent Purchase price consideration Payments to Acquire Businesses, Gross Stock-Based Compensation Share-Based Payment Arrangement, Noncash Expense James A. Brock [Member] James A. Brock George J. Schuller, Jr. [Member] George J. Schuller, Jr. Schedule of Inventories Schedule of Inventory, Current [Table Text Block] Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Basic Earnings (Loss) per Share (in dollars per share) Basic (in dollars per share) Earnings Per Share, Basic Repurchases of Common Stock Payments for Repurchase of Common Stock Total Current Assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] Subsidence Liability Subsidence Liability, Current Represents current accrued subsidence liability. Award Type Award Type [Axis] Debt-Related Financing Fees Payments of Financing Costs Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Trade Receivables, net Accounts Receivable, after Allowance for Credit Loss, Current Retained Earnings Retained Earnings (Accumulated Deficit) Series 2020 Series 2020 [Member] Series 2020 Product and Service [Axis] Product and Service [Axis] Restricted Cash—Noncurrent Restricted Cash, Noncurrent 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] Core Marine Terminal Core Marine Terminal [Member] Core Marine Terminal Pension Benefits Pension Plan [Member] Common Stock Common Stock [Member] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Current Portion of Long-Term Debt Business Combination, Recognized Liability Assumed, Long-Term Debt, Current Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Cover [Abstract] Cover [Abstract] Plant and Equipment Coal and Other Plant and Equipment [Member] Represents information related to coal and other plant and equipment. Reclassifications Reclassification, Comparability Adjustment [Policy Text Block] High CV Thermal High CV Thermal [Member] Represents information related to Pennsylvania Mining Complex. Other Operating Income and Expense, net Other Operating Income (Expense), Net, Adjusted Other Operating Income (Expense), Net, Adjusted Derivative Contract [Domain] Derivative Contract [Domain] Equity Awards Adjustments Equity Awards Adjustments [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Total Liabilities and Stockholders’ Equity Liabilities and Equity Long-Term Debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Long-term Debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Long-term Debt Nonrecurring Adjustment, Merger-Related Costs Business Combination, Pro Forma Information, Nonrecurring Adjustment, Acquisition-Related Cost [Member] Employee Stock Option Share-Based Payment Arrangement, Option [Member] Asset Retirement Obligations Asset Retirement Obligation, Current Segments [Axis] Segments [Axis] Airshafts Airshafts [Member] Represents information related to airshafts. Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Basis of Presentation [Line Items] Basis of Presentation [Line Items] Basis of Presentation Inventory Disclosure [Abstract] Tabular List, Table Tabular List [Table Text Block] Capital in Excess of Par Value Additional Paid in Capital Changes in Other Liabilities Increase (Decrease) in Other Noncurrent Liabilities Other Costs Other Nonoperating Income (Expense) Long-Term Debt Long-Term Debt [Text Block] Other Operating Income and Expense, net Other Operating Income (Expense), Net 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] General and Administrative Costs General and Administrative Costs General and Administrative Expense Long-Lived Asset, Class [Domain] Long-Lived Asset, Class [Domain] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Additional Information Segment Reporting, Other Disclosure [Abstract] Property, Plant, and Equipment [Table] Property, Plant, and Equipment [Table] Adjustment to Compensation: Adjustment to Compensation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Series 2021 Series 2021 [Member] Series 2021 Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Hedging Designation [Axis] Hedging Designation [Axis] Trade Receivables Trade Accounts Receivable [Member] Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Long-Term Debt Long-Term Debt and Lease Obligation Name Measure Name Income Taxes Income Tax Disclosure [Text Block] Accounts Payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Other Adjustments to Net Income (Loss) Other Noncash Income (Expense) Debt Instrument [Line Items] Debt Instrument [Line Items] Other Current Assets Increase (Decrease) in Other Current Assets Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Total Consideration Transferred Business Combination, Consideration Transferred Retirement Plan Type [Domain] Retirement Plan Type [Domain] Capital in Excess of Par Value Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Defined Contribution Plan [Table] Defined Contribution Plan [Table] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Advance Royalty Commitments (8.04% Weighted-Average Interest Rates) Advance Royalty Commitments [Member] Represents information related to advance royalty commitments. Name Trading Arrangement, Individual Name Cash and Cash Equivalents Cash and Cash Equivalent Components of Coal Workers' Pneumoconiosis (CWP) and Workers' Compensation Net Periodic Benefit Costs Pneumoconiosis Benefits And Workers Compensation Disclosure [Text Block] Represents disclosure of pneumoconiosis benefits and workers compensation. Coal Inventory, Raw Materials, Net of Reserves Compensation Related Costs [Abstract] Company Selected Measure Amount Company Selected Measure Amount Power Generation Power Generation [Member] Power Generation Not Designated as Hedging Instrument Not Designated as Hedging Instrument [Member] Depreciation, Depletion and Amortization Depreciation, Depletion and Amortization Depreciation, Depletion and Amortization Entity Address, Address Line Two Entity Address, Address Line Two Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Accounts and Financing Receivables [Table] Retirement Plan Name [Axis] Retirement Plan Name [Axis] Current Assets: Assets, Current [Abstract] Insurance recoveries Insurance Recoveries Revenues Business Combination, Pro Forma Information, Pro Forma Revenue Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Amount outstanding Line of Credit Facility, Fair Value of Amount Outstanding Income Tax (Benefit) Expense Income tax (benefit) expense Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Basis of Consolidation Consolidation, Policy [Policy Text Block] Net 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] Deferred Income Taxes Business Combination, Recognized Liability Assumed, Deferred Tax Liability Basis of Presentation [Table] Basis of Presentation [Table] Basis of Presentation Recognized Net Actuarial Loss (Gain) Defined Benefit Plan, Amortization of Gain (Loss) Net Income (Loss) Net Income (Loss) Net Income (Loss) Net income attributable to the SPVs Net Income (Loss) Attributable to Parent Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Less: Unamortized Debt Issuance Costs Unamortized Debt Issuance Expense Postretirement Benefits Other than Pensions Postretirement Benefits Other than Pensions Represents current liability for other postretirement defined benefit plan. Statement [Table] Statement [Table] Above Market Leases Above Market Leases [Member] Restatement Determination Date: Restatement Determination Date [Axis] Interest Income Investment Income, Interest Liabilities Assumed: Business Combination, Recognized Liability Assumed, Liability [Abstract] Property, plant and equipment Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment Damages value Loss Contingency, Damages Sought, Value Postretirement Benefits Other Than Pensions Liability, Other Postretirement Defined Benefit Plan, Noncurrent Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Numerator: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract]