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Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Cash Flow Hedges Cash Flow Hedging [Member] Common stock, shares authorized Common Stock, Shares Authorized Earnings Per Share, Basic [Abstract] Net (loss) income per common share: Net income per common share: Product and Service Product and Service [Axis] Document Fiscal Period Focus Document Fiscal Period Focus Long-term Liabilities Other Noncurrent Liabilities [Member] Debt Instrument, Interest Rate, Stated Percentage Debt instrument contractual rate (percent) Entity Shell Company Entity Shell Company Other accrued liabilities Other accrued liabilities Other Accrued Liabilities, Current Cash and Cash Equivalents, at Carrying Value, Total Cash and cash equivalents Cash and Cash Equivalent Schedule of income taxes paid by geographical area. 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United Kingdom, Pounds British Pounds Basis of Presentation and Recent Accounting Pronouncements [Line Items] Basis of presentation and recent accounting pronouncements. Currency [Axis] Deferred compensation arrangement with individual, compensation expense Deferred Compensation Arrangement with Individual, Compensation Expense Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent, Total Cash flow hedges Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent Midwest Premium Purchase Contracts [Member] Midwest Premium Purchase Contracts [Member] Midwest premium purchase contracts Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Computation of Basic and Diluted Net Income Per Share AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Property, Plant and Equipment, Net Property, Plant and Equipment, Net [Abstract] Net income per common share, Basic: Earnings Per Share, Basic, Total Basic Earnings Per Share, Basic Income Taxes Paid By Geographical Area [Table] Income Taxes Paid By Geographical Area [Table] Income taxes paid by geographical area. Employee Benefits Retirement Benefits [Text Block] Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Benefit obligation, discount rate Supplemental lease disclosures. Supplemental Lease Disclosures [Abstract] Supplemental lease disclosures: Revolving Credit Facility Revolving Credit Facility [Member] Retirement Plan Type Retirement Plan Type [Domain] Total current liabilities Liabilities, Current Proceeds from Sale of Equity Securities, FV-NI Proceeds from sale of equity securities GE Products Ge Products [Member] GE Products [Member] Increase (Decrease) in Accounts Receivable Receivables Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Hedging Designation Hedging Designation [Domain] O 2026 Q2 Dividends [Member] O 2026 Q2 Dividends. O 2026 Q2 Dividends Cash dividends, record date Dividends Payable, Date of Record Non Rule 10b51 Arr Modified Flag Non-rule 10b5-1 arr modified flag. 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Line of credit facility additional revolving commitments amount Schedule of Supplemental Balance Sheet Information Condensed Balance Sheet [Table Text Block] Antidilutive securities excluded from computation of earnings per share, amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Common stock, par value Common Stock, Par or Stated Value Per Share Billed Billed Revenues [Member] Other comprehensive (loss) income, net of tax Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Other comprehensive income, net of tax Base Rate [Member] Base Rate Euro Member Countries, Euro Euro Long-term replacement parts Long-Term Replacement Parts, Non-current Long-term replacement parts, non-current. Schedule of Total Expense Related to Benefit Plans Schedule of Costs of Retirement Plans [Table Text Block] Other long-term liabilities Other Sundry Liabilities, Noncurrent Fixed Price Sale Contracts for MWTP Fixed Price Sale Contracts for Midwest Transaction Price [Member] Fixed price sale contracts for midwest transaction price. Debt Disclosure [Abstract] Derivative [Table] Derivative [Table] Supplemental Cash Flow Elements [Abstract] Derivative notional amount Derivative, Notional Amount Current Fiscal Year End Date Current Fiscal Year End Date Debt Instrument [Table] Schedule of Long-Term Debt Instruments [Table] Expected period related to remediation expenditures for environmental contingencies period Expected Period Related To Remediation Expenditures For Environmental Contingencies Period ExpectedPeriodRelatedToRemediationExpendituresForEnvironmentalContingencies Restricted Cash and Cash Equivalents, Noncurrent, Total Restricted cash included in Other assets Restricted Cash and Cash Equivalent, Noncurrent Restricted cash - Note 11 Assets to be conveyed associated with Warrick acquisition Assets Associated With Acquisition Assets associated with acquisition. 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Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Cancellation of shares to cover tax withholdings upon common shares issued (shares) Raw materials Inventory, Raw Materials, Gross Petroleum Reserves [Axis] Interest expense capitalized as construction in progress Interest Costs Capitalized Deferred tax assets, net Deferred Income Tax Assets, Net Other Postretirement Benefits Plan Other Postretirement Benefits Plan [Member] Subsequent Event [Member] Subsequent Event Other assets Other assets Other Assets, Noncurrent Basis of Presentation and Recent Accounting Pronouncements Basis of Presentation and Significant Accounting Policies [Text Block] State and Local Jurisdiction [Member] State Accumulated Other Comprehensive Income AOCI Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) Derivative Liability, Total Derivative net liability Derivative Liability Liabilities Derivative liability Liabilities Total derivative liabilities Treasury stock, shares Treasury Stock, Common, Shares Preferred Stock, Value, Issued Preferred stock, 5,000,000 shares authorized at both June 30, 2026 and December 31, 2025; no shares were issued and outstanding at June 30, 2026 and December 31, 2025 Debt Instrument, Maturity Date Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months Estimated net mark-to-market gain before tax within next twelve months - cash flow hedges Minimum Minimum Current assets: Assets, Current [Abstract] Multiemployer Plan, Employer Contribution, Cost, Total Multiemployer plan, contributions by employer Multiemployer Plan, Employer Contribution, Cost Amortization of Intangible Assets, Total Amortization of definite-lived intangible assets Amortization of Intangible Assets Description of assumption used to determine benefit obligation Defined Benefit Plan, Assumptions Used in Calculation, Description Segment Reporting [Abstract] Accrued Environmental Loss Contingencies, Noncurrent Long-term environmental accrual - Note 6 Cash Flow Hedges: Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Current liabilities: Liabilities, Current [Abstract] Accounts Receivable, after Allowance for Credit Loss, Current Receivables, net Receivables, net Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Reclassification Adjustment, before Tax, Total Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Reclassification Adjustment, before Tax Increase in pre-tax prior service cost Commitments and Contingencies Commitments and contingencies - Note 6 Service cost Defined Benefit Plan, Service Cost Work-in-process Inventory, Work in Process, Gross Deferred Compensation Liability, Current Deferred Compensation Liability, Current, Total Current deferred compensation plan liabilities - Note 3 Accounts Receivable, before Allowance for Credit Loss, Current Accounts receivable Other Cost of Products Sold Other cost of products sold. Other cost of products sold Short-Term Debt, Total Short-Term Debt Short-term debt Rule 10b51 Arr Modified Flag Rule 10b5-1 arr modified flag. Rule 10b5-1 Arrangement Modified Fixed price sale contracts for Midwest premium. Fixed Price Sale Contracts For Midwest Premium [Member] Fixed Price Sale Contracts for MWP Current finance lease liabilities Short-term finance lease liabilities Finance Lease, Liability, Current Unpaid purchases of property and equipment Capital Expenditures Incurred but Not yet Paid 4.625% Senior Notes Senior Notes Due Two Thousand And Twenty Eight [Member] Senior notes due two thousand and twenty eight. Total other employee benefit plans Defined Benefit Plan Net Periodic Benefit Cost And Charges Relating To Other Benefit Plans Defined benefit plan net periodic benefit cost and charges relating to other benefit plans. Long-term Debt, Type Long-Term Debt, Type [Domain] Weighted Average Number of Shares Outstanding, Basic, Total Basic Weighted Average Number of Shares Outstanding, Basic Packaging Packaging [Member] Packaging. Subsequent Events Subsequent Events [Text Block] Total carrying amount Long-Term Debt Net sales: Revenue from External Customer [Line Items] APIC, Share-Based Payment Arrangement, Increase for Cost Recognition, Total Amortization of unearned equity compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Variable Rate [Domain] Ending balance Equity, Attributable to Parent Total stockholders’ equity Beginning balance Employer contributions, remainder of fiscal year Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year Statement of Stockholders' Equity [Abstract] Less: income tax benefit (expense) Other Comprehensive Income (Loss) before Reclassifications, Tax, Total Other Comprehensive Income (Loss) before Reclassifications, Tax Schedule of Income Taxes Paid by Geographical Area Scheduleof Income Taxes Paid [Table Text Block] Schedule of income taxes paid. Use of Estimates in the Preparation of Financial Statements Use of Estimates, Policy [Policy Text Block] Treasury Stock, Common [Member] Treasury Stock Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Net unrealized (loss) gain on cash flow hedges OCI, before Reclassifications, Net of Tax, Attributable to Parent Entity Address, Address Line Two Entity Address, Address Line Two Cash dividends, declared date Dividends Payable, Date Declared Domestic UNITED STATES Defined Benefit Plans: Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Debt Instrument, Name Debt Instrument, Name [Domain] Accrued Liabilities and Other Liabilities Other - Note 4 Employee Costs Employee costs. Employee costs Derivative Instruments and Hedging Activities Disclosure [Abstract] Time period within which recorded estimate of its environmental obligation may change Time Period Within Which Recorded Estimate Of Its Environmental Obligation May Change Time period within which recorded estimate of its environmental obligation may change. 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] Credit Facility Credit Facility [Axis] Net liabilities of Salaried VEBA Net Liability In Respect Of Veba Net liability in respect of VEBA Pension plan contributions Deferred Compensation Arrangement with Individual, Contributions by Employer Cost of Goods and Services Sold, Total Cost of Product and Service Sold Cost of products sold, excluding depreciation and amortization Total of income and expense line items presented in our Statements of Consolidated Income in which the effects of cash flow hedges are recorded Schedule of Availability and Usage of Revolving Credit Facility Schedule of Line of Credit Facilities [Table Text Block] Treasury Stock, Value, Total Treasury Stock, Value Treasury stock, at cost, 6,835,286 shares at both June 30, 2026 and December 31, 2025 Foreign Tax Jurisdiction [Member] Pension Plans Pension Plan [Member] Accounting Standards Update [Extensible Enumeration] Foreign exchange contracts Foreign Currency Foreign Exchange Contract [Member] Entity Address, City or Town Entity Address, City or Town Billing Status, Type Billing Status, Type [Axis] Number of Reportable Segments Number of reportable segments Supply Chain Financing Supply Chain Financing Policy Policy [Text Block] Supply chain financing policy. Security Exchange Name Security Exchange Name Credit Facility Credit Facility [Domain] Property, Plant and Equipment, Gross, Ending Balance Property, Plant and Equipment, Gross, Beginning Balance Property, plant and equipment, gross Property, Plant and Equipment, Gross Warrick Pension Plan Warrick Pension Plan [Member] Warrick pension plan. Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Sales Short [Member] Schedule Of Interest Expense On Senior Notes And Revolving Credit Facility Table [Text Block] Schedule of interest expense on senior notes and revolving credit facility. Summary of Interest Expense Relating to Senior Notes and Revolving Credit Facility Inventories Inventories Inventory, Net Total cash, cash equivalents and restricted cash presented on our Statements of Consolidated Cash Flows Cash, cash equivalents and restricted cash at beginning of period Cash, cash equivalents and restricted cash at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Statistical Measurement Statistical Measurement [Domain] Total current assets Assets, Current Document Period End Date Document Period End Date Other Income and Expenses [Abstract] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Domain] Defined contribution plan, cost Defined Contribution Plan, Cost Other Other Assets, Miscellaneous, Noncurrent (Gain) loss on disposition of property, plant and equipment Gain (Loss) on Disposition of Property Plant Equipment, Total Gain on disposition of property, plant and equipment Loss on disposition of property, plant and equipment Research and development costs Research and development costs. Research and development costs Statement of Financial Position [Abstract] 4.50% Senior Notes Unsecured Senior Notes Due June One Two Thousand And Thirty One [Member] Unsecured Senior notes due June one two thousand and thirty one. Other comprehensive income (loss), net of tax - Note 7: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Potential increase in environmental costs Loss Contingency, Range of Possible Loss, Portion Not Accrued Long-Term Liabilities Other Liabilities, Noncurrent [Abstract] Not Designated as Hedging Instrument Not Designated as Hedging Instrument [Member] Total liabilities Liabilities Reclassification from AOCI Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Reclassification of unrealized gain upon settlement of cash flow hedges Business interruption insurance advances Gain on business interruption insurance recoveries Gain on Business Interruption Insurance Recovery Foreign Income Tax Expense (Benefit), Continuing Operations, Total Foreign Foreign Income Tax Expense (Benefit), Continuing Operations All Currencies [Domain] Dividends, Total Cash dividends declared Dividends Hedged Cost of Alloyed Metal Hedged cost of alloyed metal. 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Summary of Fair Value of Outstanding Senior Notes Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Taxes Payable, Current, Total Accrued income taxes and other taxes payable Taxes Payable, Current Less: income tax expense Reclassification from AOCI, Current Period, Tax, Total Reclassification from AOCI, Current Period, Tax Less: income tax benefit (expense) Less: income tax benefit Supplemental Balance Sheet Information Supplemental Balance Sheet Disclosures [Text Block] Derivative, Gain (Loss) on Derivative, Net, Total Derivative, Gain (Loss) on Derivative, Net Total gain recognized in our Statements of Consolidated Income related to cash flow hedges Amended Credit Agreement Amended Credit Agreement [Member] Amended credit agreement. Uncleared cash disbursements Bank Overdrafts Number of Operating Segments Number of operating segments Timing of Transfer of Good or Service Timing of Transfer of Good or Service [Domain] Business, Product and Geographical Area Information Segment Reporting Disclosure [Text Block] Income Taxes Paid By Geographical Area [Line Items] Income Taxes Paid By Geographical Area [Line Items] Income taxes paid by geographical area. 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Effective Income Tax Rate Reconciliation for Return to Provision Differences Effective income tax rate reconciliation related to return to provision differences Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Percent Effective income tax rate reconciliation, related to non-deductible compensation expense, percent Derivative Asset, Statement of Financial Position [Extensible Enumeration] Other Products [Member] Other Products [Member] Other Products Schedule Of Accounts Notes Loans And Financing Receivable [Table] Accounts and Financing Receivables [Table] Earnings Per Share [Text Block] Earnings Per Share Plant Overhead Plant overhead. Plant overhead Gross unrecognized tax benefits that would impact effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Net income Net income Inventories Increase (Decrease) in Inventories Increase (Decrease) in Inventories, Total Inventories Alloying Metals Alloy Metal Hedge [Member] Alloy Metal Hedge[Member] Electricity metal reclassification due to forecasted transactions. Electricity Metal Reclassification Due To Forecasted Transactions [Member] Electricity Metal Reclassification Due To Forecasted Transactions Gain on disposition of non-operating property, plant and equipment Gain (Loss) on Disposition of non-operating Property Plant Equipment Included in Restructuring Expenses Gain (loss) on disposition of non-operating property plant equipment included in restructuring expenses. 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Hedged cost realized gains upon settlement Less: Outstanding letters of credit under Revolving Credit Facility Letters of Credit Outstanding, Amount Income Tax Disclosure [Abstract] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value, Recurring and Nonrecurring [Table] Other Accrued Liabilities Accrued Liabilities and Other Liabilities [Abstract] Gross unrecognized tax benefits Unrecognized Tax Benefits, Ending Balance Unrecognized Tax Benefits, Beginning Balance Unrecognized Tax Benefits Additional Paid in Capital Additional Paid-in Capital [Member] Measurement Frequency Measurement Frequency [Domain] Automotive Extrusions Automotive Extrusions [Member] Automotive Extrusions [Member] Senior Notes Senior Notes [Member] Change in Accounting Principle, Accounting Standards Update, Adoption Date Trading Symbol Trading Symbol Summary of Percentages of Expected Variable Priced Purchases of Metals Alloys and Energy Percentage Of Expected Variable Priced Purchases Of Metal Alloys And Energy Table [Text Block] Percentage of expected variable priced purchases of metal alloys and energy. Gain on Business Interruption Insurance Recovery, Statement of Income or Comprehensive Income [Extensible Enumeration] Subsequent Event Type [Axis] Line of credit mature description Line of Credit Facility, Description Employee-related Liabilities, Current, Total Accrued salaries, wages and related expenses Employee-related Liabilities, Current Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Line of credit maximum revolving commitment Percentage of unused line fee Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Net assets of Salaried VEBA Other Non Current Postretirement Obligation Other non current postretirement obligation. Effective income tax rate reconciliation, related to federal research & development credit, percent (decrease) Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent Add: dilutive effect of non-vested common shares, restricted stock units and performance shares Incremental Common Shares Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends Accumulated Other Comprehensive (Loss) Income Equity Components [Axis] Derivative Asset, Noncurrent, Statement of Financial Position [Extensible Enumeration] Other income, net Nonoperating Income (Expense) Accrued Environmental Loss Contingencies, Current Short-term environmental accrual - Note 7 Equity Component Equity Component [Domain] Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total Common shares issued (including impacts from Long-Term Incentive programs) (shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Statement of Comprehensive Income [Abstract] Other Assets Other Assets [Abstract] Maximum Maximum Cash dividends, payable date Dividends Payable, Date to be Paid Designated as Hedging Instrument Designated as Hedging Instrument [Member] Statistical Measurement Statistical Measurement [Axis] Common stock, par value $0.01, 90,000,000 shares authorized at both June 30, 2026 and December 31, 2025; 23,184,378 shares issued and 16,349,092 shares outstanding at June 30, 2026; 23,045,729 shares issued and 16,210,443 shares outstanding at December 31, 2025 Common Stock, Value, Issued Repayment of finance lease Finance Lease, Principal Payments Deferred Bonus and Profit Sharing Arrangements, Individual Contracts, Type of Deferred Compensation Deferred Bonus and Profit Sharing Arrangements, Individual Contracts, Type of Deferred Compensation [Axis] Derivative Asset, Current Derivative asset current Dividends [Axis] Components of cash, cash equivalents and restricted cash: Cash and Cash Equivalents [Abstract] Principles of Consolidation and Basis of Presentation Consolidation, Policy [Policy Text Block] Type of Reserve [Domain] Amortization of Debt Issuance Costs Amortization of debt issuance costs Increase Decrease In Noncurrent Assets And Liabilities Net Long-term assets and liabilities, net Increase (decrease) in noncurrent assets and liabilities net. Preferred stock, shares authorized Preferred Stock, Shares Authorized Accrued interest Interest Payable, Current Total costs and expenses Costs and Expenses Payment, Tax Withholding, Share-Based Payment Arrangement Cancellation of shares to cover tax withholdings upon common shares issued Accounts Notes And Loans Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Entity Registrant Name Entity Registrant Name Debt and Credit Facility Debt Disclosure [Text Block] Other income, net - Note 8 Other income, net - Note 8 Other Nonoperating Income (Expense), Total Other Nonoperating Income (Expense) Other income (expense), net - Note 8 Accumulated Other Comprehensive Income Loss [Table] Accumulated Other Comprehensive Income (Loss) [Table] Subsequent Events [Abstract] Other Income, Net Schedule of Other Nonoperating Income (Expense) [Table Text Block] Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] SOFR Income tax provision Income Tax Expense (Benefit), Total Total Income Tax Expense (Benefit) Income tax provision Income tax benefit (provision) Measurement Frequency Measurement Frequency [Axis] Payments to Acquire Productive Assets, Total Capital expenditures Payments to Acquire Productive Assets Costs and expenses: Costs and Expenses [Abstract] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Other Income, Net Other Income and Other Expense Disclosure [Text Block] Other (Expense) Income, Net Accumulated Other Comprehensive Income (Loss), Net of Tax, Total Accumulated Other Comprehensive Income (Loss), Net of Tax AOCI Federal Income Tax Expense (Benefit), Continuing Operations, Total Domestic Federal Income Tax Expense (Benefit), Continuing Operations Total assets Assets Trade Receivables, Net Accounts Receivable, after Allowance for Credit Loss, Current [Abstract] Accrued annual contribution to Salaried VEBA Accrued Annual Contribution to Salaried Voluntary Employees Beneficiary Association, Current Accrued annual contribution to salaried voluntary employees beneficiary association, current. Income Statement [Abstract] Retirement Plan Name Retirement Plan Name [Domain] Trade accounts receivable sold Accounts Receivable, Sale Other Selling, General and Administrative Expense Other selling, general and administrative costs Defined Benefit Plan, Amortization of Gain (Loss) Amortization of net actuarial gain Diluted Net income per common share, Diluted: Earnings Per Share, Diluted, Total Earnings Per Share, Diluted Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Significant Segment Expenses Provided to CODM Position Position [Domain] Increase (Decrease) in Accounts Payable, Trade Accounts payable City Area Code City Area Code Schedule of Fair Value of Plan Assets Schedule of Defined Benefit Plans Disclosures [Table Text Block] Proceeds from Lines of Credit, Total Proceeds from Lines of Credit Borrowings under the Revolving Credit Facility Total borrowings incurred Debt instrument aggregate principal amount Total debt Buildings and leasehold improvements Buildings and Improvements, Gross Line of credit facility, maximum borrowing capacity Revolving Credit Facility borrowing commitment Line of Credit Facility, Maximum Borrowing Capacity Schedule Of Defined Benefit Plans Disclosures [Table] Defined Benefit Plan [Table] Dividends, Cash, Total Cash dividends declared Dividends, Cash Segment Reporting Information [Line Items] Midwest Premium Sale Contracts [Member] Midwest Premium Sale Contracts [Member] Midwest premium sale contracts Retirement Plan Name Retirement Plan Name [Axis] Letter of Credit Letter of Credit [Member] Derivative Liability, Current Derivative liabilities current Property, plant and equipment, net Property, plant and equipment, net Property, Plant and Equipment, Net Finance lease liabilities arising from obtaining finance lease assets Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Operating Income (Loss) Operating income Operating (loss) income Retained Earnings Retained Earnings [Member] Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Defined Benefit Plans: Actuarial Loss Share-Based Payment Arrangement, Noncash Expense, Total Non-cash equity compensation Share-Based Payment Arrangement, Noncash Expense Long-term portion of operating lease liabilities Operating Lease, Liability, Noncurrent Level 1 Fair Value, Inputs, Level 1 [Member] Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Net cash (used in) provided by financing activities Change in Accounting Principle, Accounting Standards Update, Adopted [true false] Unamortized issuance costs Unamortized debt issuance costs Unamortized Debt Issuance Expense Deferred tax liabilities Deferred Income Tax Liabilities, Net Other (expense) income: Nonoperating Income (Expense) [Abstract] Derivative liabilities noncurrent Derivative Liability, Noncurrent Derivative liabilities noncurrent Derivative Contract Derivative Contract [Domain] Accrual for Environmental Loss Contingencies, Ending Balance Accrual for Environmental Loss Contingencies, Beginning Balance Accrual for Environmental Loss Contingencies, Total Environmental accrual Accrual for Environmental Loss Contingencies Salaried VEBA Salaried V E B A [Member] Salaried VEBA [Member] Foreign Non-US [Member] Income Tax Jurisdiction [Domain] Entity Interactive Data Current Entity Interactive Data Current Cash flows from operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Products Transferred Over Time Transferred over Time [Member] Repayments of Lines of Credit Repayment of borrowings under the Revolving Credit Facility Repayments of Lines of Credit, Total Repayment of borrowings Effective income tax rate reconciliation, foreign withholding tax, percent Effective Tax Rate Reconciliation Foreign Withholding Tax Effective tax rate reconciliation, foreign withholding tax. Fixed Price Purchase Contracts for MWTP Fixed price purchase contracts for MWTP Fixed Price Purchase Contracts for Midwest Transaction Price [Member] Fixed price purchase contracts for midwest transaction price. Cash dividends declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Borrowing base availability Line of Credit Facility, Current Borrowing Capacity Freight costs Freight costs Freight costs. Entity Tax Identification Number Entity Tax Identification Number Long-term Debt, Type Long-Term Debt, Type [Axis] Operating supplies Other Inventory, Supplies, Gross Construction in progress Construction in Progress, Gross Local Phone Number Local Phone Number Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Net periodic postretirement and postemployment benefit cost relating to defined benefit plans Net periodic postretirement and postemployment benefit cost Net periodic postretirement and postemployment benefit cost Total net periodic postretirement and postemployment benefit cost Denominator – Weighted-average common shares outstanding (in thousands): Weighted-average number of common shares outstanding (in thousands): Weighted Average Number of Shares Outstanding, Diluted [Abstract] Purchase Long [Member] Fixed Price Purchase Contracts For Midwest Premium [Member] Fixed Price purchase contracts for midwest premium. Fixed Price Purchase Contracts for MWP Accounting Policies [Abstract] Other Accrued Liabilities Other Current Liabilities [Member] Net sales Revenue from Contract with Customer, Excluding Assessed Tax All other, net Other Nonoperating Income Expense Net Other nonoperating income expense net. Schedule Of Entity Wide Information Revenue From External Customers By Products And Services [Table] Segment Reporting, Revenue from External Customer, Product and Service [Table] Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration] Inventories Inventory, Net [Abstract] Other Postretirement Benefits Expense (Reversal of Expense), Noncash Non-cash postretirement and postemployment defined benefit plan cost Shares available for awards (shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant Accrued salaries, wages and related expenses Accrued Bonuses Products Transferred at a Point in Time Transferred at Point in Time [Member] Entity Emerging Growth Company Entity Emerging Growth Company Accounting Standards Update 202510 [Member] Accounting Standards Update 2025-10.