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2026 and 22,437,379 issued and 12,805,909 outstanding at December 31, 2025 Common Stock, Value, Issued Wages and benefits Employee-related Liabilities, Current Schedule of Long-term Debt Schedule of Long-Term Debt Instruments [Table Text Block] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Number of active mines Number Of Active Mines Number Of Active Mines Restatement Determination Date Restatement Determination Date Sales and maturities of investment securities Proceeds from Sale, Maturity and Collection of Investments Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Total long-term debt Long-Term Debt and Lease Obligation, Including Current Maturities Workers’ compensation and black lung obligations Worker's Compensation And Black Lung Obligations [Member] Worker's Compensation And Black Lung Obligations Non-GAAP cost of coal sales Non-GAAP Cost Of Sales Non-GAAP Cost Of Sales Schedule of Restricted Investments and Deposit Assets Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block] Amendment Flag Amendment Flag Current liabilities: Liabilities, Current [Abstract] Common stock repurchases and related expenses Treasury Stock Value, Acquired, Cost Method And Related Expenses Treasury Stock Value, Acquired, Cost Method And Related Expenses Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Total other expenses Operating Expenses And Other Operating Expenses And Other Additional DTA Investment Additional DTA Investment [Member] Additional DTA Investment Related Party Transactions Related Party Transactions Disclosure [Text Block] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Expenditures for the period Asset Retirement Obligation, Liabilities Settled Reconciliation of Cash and Cash Equivalents and Restricted Cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation [Abstract] Entity Address, State or Province Entity Address, State or Province PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Amounts reclassified from accumulated other comprehensive loss Reclassification out of Accumulated Other Comprehensive Income [Member] Other acquired intangibles, net of accumulated amortization of $44,825 and $43,072 as of June 30, 2026 and December 31, 2025, respectively Intangible Asset, Excluding Goodwill, after Accumulated Amortization Weighted average shares - basic (in shares) Weighted Average Number of Shares Outstanding, Basic Retirement Benefits [Abstract] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Total asset retirement obligations at December 31, 2025 Total asset retirement obligations at June 30, 2026 Asset Retirement Obligation Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current Entity Address, City or Town Entity Address, City or Town Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Coal royalty expense Royalty Expense Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Accrued expenses and other current liabilities Total accrued expenses and other current liabilities Accrued Liabilities And Other Liabilities, Current Accrued Liabilities And Other Liabilities, Current Increase (decrease) in liability for pension obligations Increase (Decrease) in Obligation, Pension Benefits Other 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Operating Results and Capital Expenditures Segment Reporting [Table Text Block] (Gain) loss on disposal of assets, net Gain (Loss) on Disposition of Property Plant Equipment Total other comprehensive income (loss), net of tax Other comprehensive income, net Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Notes payable and other Long-Term Debt Supplemental disclosure of noncash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Document Period End Date Document Period End Date 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] Capital Stock Equity [Text Block] Costs and expenses: Costs and Expenses [Abstract] Security Exchange Name Security Exchange Name Treasury stock, at cost: 9,811,396 shares at June 30, 2026 and 9,631,470 shares at December 31, 2025 Treasury Stock, Common, Value Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Minimum cash level threshold Line Of Credit, Covenant Compliance, Minimum Cash Level Threshold Line Of Credit, Covenant Compliance, Minimum Cash Level Threshold Net Loss Per Share Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Earnings Per Share [Abstract] Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Total liabilities Liabilities Income tax (expense) benefit Other Comprehensive 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Agreement, Term Employee benefit costs Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Credit Facility [Domain] Credit Facility [Domain] Related Party Transactions [Abstract] Related Party Transactions [Abstract] Operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Compensation Amount Outstanding Recovery Compensation Amount Freight and handling costs Freight And Handling Costs Freight And Handling Costs Individual: Individual [Axis] Weighted average shares - diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined Benefit Plans and 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Restricted Investments Other comprehensive loss, net of tax: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Schedule of Net Periodic Benefit Cost Schedule of Net Benefit Costs [Table Text Block] Coal, Thermal Coal, Thermal [Member] Coal, Thermal [Member] Owned and lease mineral rights, accumulated depletion and amortization Mineral Properties, Accumulated Depletion Concentration Risk Type [Domain] Concentration Risk Type [Domain] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Current portion of long-term debt Less current portion Long-Term Debt and Lease Obligation, Current Segment Information Segment Reporting [Text Block] Minimum Minimum [Member] Amounts borrowed Long-Term Line of Credit Dividend equivalents Dividend Equivalents Dividend Equivalents Total deposits, net of current portion Deposits Assets, Noncurrent Expiration Date Trading Arrangement Expiration Date Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] 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] Net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Asset Retirement Obligation Disclosure [Abstract] Asset Retirement Obligation Disclosure [Abstract] Exercise Price Award Exercise Price Investing activities: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Segment Reporting [Line Items] Segment Reporting [Line Items] Authorized share repurchases Share Repurchase Program, Authorized, Amount 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] Top 10 Customers Top Ten Customers [Member] Top Ten Customers [Member] Principal repayments of long-term debt Repayments of Long-Term Debt 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 Total costs and expenses Costs and Expenses Adoption Date Trading Arrangement Adoption Date Total stockholders’ equity Beginning balance Ending balance Equity, Attributable to Parent Total other expense, net Nonoperating Income (Expense) Reclamation-Related Obligations Reclamation-related obligations Reclamation Related Obligations [Member] Reclamation Related Obligations [Member] 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 Workers' Compensation Liability, Current Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Insider Trading Policies and Procedures [Line Items] Financing leases Finance Lease, Liability Other, net Proceeds from (Payment for) Other Financing Activity 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Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Number of operating segments Number of Operating Segments Antidilutive securities excluded from computation of earnings per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Entity Central Index Key Entity Central Index Key All Adjustments to Compensation All Adjustments to Compensation [Member] Other, net Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item Equity [Abstract] Equity [Abstract] 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 provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Accounts Receivable Accounts Receivable [Member] Stockholders’ Equity Equity, Attributable to Parent [Abstract] Income Statement [Abstract] Income Statement [Abstract] Document Transition Report Document Transition Report Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Deferred income taxes Deferred Income Tax Assets, Net Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Black Lung Postretirement Health Coverage [Member] Other Commitments [Domain] Other Commitments [Domain] City Area Code City Area Code Accumulated Other Comprehensive (Loss) Income AOCI Attributable to Parent [Member] Geographic Concentration Risk Geographic Concentration Risk [Member] All Individuals All Individuals [Member] Pension obligations Liability, Defined Benefit Pension Plan, Noncurrent Name Forgone Recovery, Individual Name Saleable coal Inventory, Finished Goods, Net of Reserves Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Statement [Line Items] Statement [Line Items] Total assets Assets Grant income Government Assistance, Income, Increase (Decrease) Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Interest expense Interest expense Interest Expense, Nonoperating Financial payments and other performance obligations Financial Payments and Other Performance Obligations [Member] Financial Guarantee and Other [Member] Other comprehensive income (loss) before reclassifications OCI, before Reclassifications, Net of Tax, Attributable to Parent PEO PEO [Member] Taxes other than income taxes Accrual for Taxes Other than Income Taxes, Current Statement of Other Comprehensive Income [Abstract] Statement of Other Comprehensive Income [Abstract] Other non-current liabilities Other Liabilities, Noncurrent Retirement Plan Type [Axis] Retirement Plan Type [Axis] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Coal, Met Coal, Met [Member] Coal, Met [Member] Payables and Accruals [Abstract] Retained Earnings Retained Earnings [Member] Revolving Credit Facility Revolving Credit Facility [Member] Asset Retirement Obligations Asset Retirement Obligation Disclosure [Text Block] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Amortization of net actuarial loss Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Total deposits Deposit Assets 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 loss per common share (in dollars per share) Earnings Per Share, Diluted Accumulated Other 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Commitment [Line Items] Long-Term Purchase Commitment [Line Items] Financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Coal revenues Revenues Revenue from Contract with Customer, Excluding Assessed Tax Workers’ compensation and black lung obligations Liability, Defined Benefit Plan, Postretirement Black Lung Health Coverage And Worker's Compensation, Noncurrent Liability, Defined Benefit Plan, Postretirement Black Lung Health Coverage And Worker's Compensation, Noncurrent Interest cost Defined Benefit Plan, Interest Cost Depreciation, depletion and amortization Depreciation, Depletion And Amortization, Excluding Acquired Intangibles Depreciation, Depletion And Amortization, Excluding Acquired Intangibles Surety Bond Surety Bond [Member] Inventories, net Inventory Disclosure [Text Block] Other revenues Other Income Value of shares repurchased Stock Repurchased During Period, Value Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Revenue Revenue from Contract with Customer [Text Block] Materials, supplies and other, net Inventory, Raw Materials and Supplies, Net of Reserves Other, net Payment for (Proceeds from) Other Investing Activity Segment Reporting [Table] Segment Reporting [Table] Accrued Expenses and Other Current Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] 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] (Loss) income from operations Operating Income (Loss) Freight accrual Accrued Freight, Current Accrued Freight, Current Estimated coal revenues 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 Stock-based compensation, issuance of common stock for share vesting, and common stock reissuances Share-Based Compensation, Issuance Of Stock For Share Vesting And Stock Reissuance Share-Based Compensation, Issuance Of Stock For Share Vesting And Stock Reissuance Collateral Held [Axis] Collateral Held [Axis] Number of shares repurchased (in shares) Stock Repurchased During Period, Shares 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] Service cost Defined Benefit Plan, Service Cost Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Common stock, shares issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] Treasury stock, at cost (in shares) Treasury Stock, Common, Shares Government Grants Government Assistance [Policy Text Block] Asset retirement obligations Long-term portion Asset Retirement Obligations, Noncurrent Accumulated Other Comprehensive Loss Comprehensive Income (Loss) Note [Text Block] Cost of coal sales (exclusive of items shown separately below) Cost of coal 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] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Capital contributions to equity affiliates Payments To Acquire Equity Method Investments, Capital Contributions Payments To Acquire Equity Method Investments, Capital Contributions Deferred income taxes Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Defined contribution plan, cost Defined Contribution Plan, Cost Entity Small Business Entity Small Business Total comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Termination Date Trading Arrangement Termination Date Other Commitments [Axis] Other Commitments [Axis] Less current portion Deposits Assets, Current 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] Export Coal Revenue Export Coal Revenue [Member] Export Coal Revenue Other non-current assets Other Assets, Noncurrent Weighted average number of shares, impact of securities excluded from shares due to the company incurring net loss for the period (in shares) Weighted Average Number Of Shares, Impact Of Securities Excluded From Shares, Due To Net Loss Incurred, During The Period Weighted Average Number Of Shares, Impact Of Securities Excluded From Shares, Due To Net Loss Incurred During The Period Document Type Document Type Fair Value as of Grant Date Award Grant Date Fair Value Collateral Pledged Collateral Pledged [Member] Common stock repurchases and related expenses Payments For Repurchase Of Common Stock And Related Expenses Payments For Repurchase Of Common Stock And Related Expenses Amortization of and adjustments to employee benefit costs Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent Black lung Liability, Defined Benefit Plan, Current Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] ABL Facility Asset-Based Revolving Credit Facility [Member] Asset-Based Revolving Credit Facility Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Business and Basis of Presentation Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Employee Benefit Plans Compensation and Employee Benefit Plans, Other than Share-Based Compensation [Text Block] Loss before income taxes (Loss) income 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] Commitments and Contingencies (Note 14) Commitments and Contingencies Total revenues Total revenues Revenues Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Equity loss in affiliates Equity loss in affiliates Income (Loss) from Equity Method Investments Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Contract term Revenue, Term Of Contract Revenue, Term Of Contract Long-term Purchase Commitment [Table] Long-Term Purchase Commitment [Table] Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Inventories, net Total inventories, net Inventory, Net All Award Types Award Type [Domain] Workers’ compensation obligations Workers' Compensation Obligations [Member] Workers' Compensation Obligations Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Fair Value of Financial Instruments and Fair Value Measurements Fair Value Disclosures [Text Block] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] PEO Name PEO Name Geographical [Axis] Geographical [Axis] Total long-term restricted cash Restricted Cash Collateral for black lung obligations Defined Benefit Plan, Collateral Defined Benefit Plan, Collateral Other segment items Segment Reporting, Other Segment Item, Amount Other commitment (as a percent) Other Commitment, Percentage Other Commitment, Percentage Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Cash and cash equivalents and restricted cash at beginning of period Cash and cash equivalents and restricted cash at end of period Total cash and cash equivalents and restricted cash shown in the Condensed Consolidated Statements of Cash Flows Cash, Cash Equivalent, Restricted Cash, and Restricted Cash 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Debt Instrument [Axis] Stock-based compensation Share-Based Payment Arrangement, Noncash Expense Amount of related party transaction Related Party Transaction, Amounts of Transaction Customer [Domain] Customer [Domain] Schedule of Inventories, Net Schedule of Inventory, Current [Table Text Block] Basic loss per common share (in dollars per share) Earnings Per Share, Basic Total share repurchase price Payments for Repurchase of Common Stock 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] Trade accounts receivable, net of allowance for credit losses of $2,714 and $2,519 as of June 30, 2026 and December 31, 2025, respectively Accounts Receivable, after Allowance for Credit Loss, Current Retained earnings Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] Long-term restricted cash 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] Pension Pension Plan [Member] Common Stock Common Stock [Member] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Reclassifications Reclassification, Comparability Adjustment [Policy Text Block] Export Non-US [Member] Concentration risk (as a percent) Concentration Risk, Percentage Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Equity Awards Adjustments Equity Awards Adjustments [Member] Total liabilities and stockholders’ equity Liabilities and Equity Number of customers exceeding 10% of total trade accounts receivable, net Number Of Customers Number Of Customers Employee Stock Option Share-Based Payment Arrangement, Option [Member] 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] Asset retirement obligations Less current portion Asset Retirement Obligation, Current Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Geographic Distribution [Domain] Geographic Distribution [Domain] Trading securities Debt Securities, Trading Inventory Disclosure [Abstract] Inventory Disclosure [Abstract] Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Miscellaneous expense, net Miscellaneous expense, net Other Nonoperating Income 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