Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Weighted-average common shares outstanding (in thousands): Denominator (in thousands): Weighted Average Number of Shares Outstanding, Diluted [Abstract] Trading Arrangement: Trading Arrangement [Axis] Maximum Maximum [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] Income Tax Jurisdiction, Domestic Federal Income Tax Jurisdiction, Domestic Federal [Member] Unrealized foreign exchange (gain) loss, net Unrealized Gain (Loss) on Derivatives and Commodity Contracts Title of 12(b) Security Title of 12(b) Security Net (loss) income available to common stockholders, diluted Net Income (Loss) Available to Common Stockholders, Diluted Document Fiscal Year Focus Document Fiscal Year Focus Weighted average interest rate of debt (as a percent) Debt, Weighted Average Interest Rate Adjustment to Compensation, Amount Adjustment to Compensation Amount Financial Instrument [Axis] Financial Instrument [Axis] Number Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Segment Reporting [Abstract] Segment Reporting [Abstract] Deferred Stock Units (DSUs) Deferred Stock Units (DSUs) [Member] Deferred Stock Units (DSUs) Increase in equipment Property, Plant, and Equipment, before Accumulated Depreciation, Period Increase (Decrease) Common stock: $0.01 par value, 200,000,000 authorized shares; 42,197,964 issued shares at June 30, 2026 and September 30, 2025 Common Stock, Value, Issued Shares withheld to satisfy employee tax obligations Payment, Tax Withholding, Share-Based Payment Arrangement Accrued salaries and wages Employee-related Liabilities, Current Schedule of Total Long-Term Carrying Value of Debt and Finance Lease Liabilities Schedule of Long-Term Debt Instruments [Table Text Block] Other Other Assets, Miscellaneous, Noncurrent Performance period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Requisite Service Period Products and services transferred over time Transferred over Time [Member] Line of Credit Line of Credit [Member] Restatement Determination Date Restatement Determination Date Derivative Instrument [Axis] Derivative Instrument [Axis] Proceeds from sale of business and fortress assets, net of cash and transaction costs Cash proceeds Proceeds from Divestiture of Businesses Share-based compensation payment award performance percentage Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Target, Percentage Of Shares Earned Share-Based Compensation Arrangement By Share-Based Payment Award, Performance Target, Percentage Of Shares Earned Amendment Flag Amendment Flag Current liabilities: Liabilities, Current [Abstract] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Disposal Group Classification [Axis] Disposal Group Classification [Axis] Gain on sale of Fortress assets Gain on sale of Fortress assets Gain (Loss) on Disposition of Other Assets Loss Contingencies [Table] Loss Contingencies [Table] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Investment Benchmark Investment Benchmark [Member] Investment Benchmark 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] Property, Plant, and Equipment [Abstract] Property, Plant, and Equipment [Abstract] Entity Address, State or Province Entity Address, State or Province PEO Total Compensation Amount PEO Total Compensation Amount Unrealized foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Asset Class: Assets, Fair Value Disclosure [Abstract] Capital expenditures Segment Reporting, Long-Lived Asset, Expenditure for Addition Asset Acquisition [Axis] Asset Acquisition [Axis] Number of shares available from conversion (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Shares Converted Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Shares Converted Intangible assets, net Intangible Asset, Excluding Goodwill, after Accumulated Amortization Outstanding at beginning of period (in shares) Outstanding at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Basic (in shares) Weighted-average common shares outstanding for basic net (loss) income per share (in shares) Weighted Average Number of Shares Outstanding, Basic Purchased of salt-treatment materials Related Party Transaction, Purchases from Related Party Inventory allowance Inventory Valuation Reserves Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Loss Contingencies [Line Items] Loss Contingencies [Line Items] Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current Work in process Inventory, Work in Process, Net of Reserves Contingent consideration period Business Combination, Contingent Consideration, Liability, Earn-out Period Business Combination, Contingent Consideration, Liability, Earn-out Period Customer Relationships Customer Relationships [Member] Net gains to be reclassified from accumulated other comprehensive loss to earnings during the next 12 months Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months Entity Address, City or Town Entity Address, City or Town Schedule of Supplemental Non-cash Activities Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Liabilities related to non-qualified savings plan Liabilities Related to Nonqualified Savings Plan, Fair Value Disclosure This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. These liabilities are related to investments carried in the company's Non-qualified Savings Plan. Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Unrealized gain (loss) from change in pension obligations, tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax Salt-Treatment Material Purchase Salt-Treatment Material Purchase [Member] Salt-Treatment Material Purchase Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] SOP SOP [Member] SOP Salt Salt [Member] An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Title and Position [Domain] Title and Position [Domain] Carrying value of asset to be disposed of Disposal Group, Including Discontinued Operation, Assets Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Released from restriction (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] Product cost Product [Member] Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Net (loss) income available to common stockholders, basic Net Income (Loss) Available to Common Stockholders, Basic Significant Other Observable Inputs (Level Two) Fair Value, Inputs, Level 2 [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Aggregate principal amount of credit facility Line of Credit Facility, Maximum Borrowing Capacity Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Other comprehensive loss before reclassifications OCI, before Reclassifications, before Tax, Attributable to Parent Scorecard PSUs Scorecard PSUs [Member] Scorecard PSUs Accounting Pronouncements Issued Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Litigation Case [Axis] Litigation Case [Axis] Schedule of Segment Information Segment Reporting [Table Text Block] Unrealized income (loss) on cash flow hedges, tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax Amortization of deferred financing costs Amortization of Debt Issuance Costs Related Party [Axis] Related and Nonrelated Parties [Axis] Net current period other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Deferred Revenue Revenue from Contract with Customer [Policy Text Block] Schedule of Other Liabilities Schedule of Accrued Liabilities [Table Text Block] Repayments under revolving credit facility Repayments of Lines of Credit Senior Notes Due 2027 Senior Notes Due 2027 [Member] Senior Notes Due 2027 PROPERTY, PLANT AND EQUIPMENT, NET Property, Plant, and Equipment [Text Block] Document Period End Date Document Period End Date Cancelled/expired (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period 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] Ogden, Utah Facility Ogden, Utah Facility [Member] Ogden, Utah Facility Consumer & Industrial Salt Consumer & Industrial Salt [Member] Consumer & Industrial Salt [Member] Aggregate principal amount Debt Instrument, Face Amount Fortress Fortress [Member] Fortress Security Exchange Name Security Exchange Name Debt instrument, term Debt Instrument, Term Treasury stock, at cost — 226,753 shares at June 30, 2026 and 497,420 shares at September 30, 2025 Treasury Stock, Common, Value Weighted-average exercise price, granted (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Total liabilities at fair value Liabilities, Fair Value Disclosure Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Consolidation Items [Domain] Consolidation Items [Domain] Current portion of operating lease liabilities Operating Lease, Liability, Current Accrued interest Interest Payable, Current Schedule of Property, Plant and Equipment, Net Property, Plant, and Equipment [Table Text Block] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] NET (LOSS) INCOME 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] Trading Symbol Trading Symbol Highway Salt Highway Salt [Member] Highway Salt [Member] Assets included in sale of net book value Asset, Held-for-Sale, Not Part of Disposal Group, Current Geographical [Domain] Geographical [Domain] 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] Share-based payment arrangement, nonvested award, option, cost not yet recognized, amount Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Income taxes payable Accrued Income Taxes, Current Company Selected Measure Name Company Selected Measure Name Amounts reclassified from AOCL Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Modifier change Share-Based Compensation By Share-Based Arrangement, Modifier Change Share-Based Compensation By Share-Based Arrangement, Modifier Change Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Natural Gas Instruments, Net Energy Related Derivative [Member] Non-cash activities: Noncash Investing and Financing Items [Abstract] Benefit Plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Total principal amount of debt Long-Term Debt, Gross Credit Facility [Domain] Credit Facility [Domain] Related Party Transactions [Abstract] Miscellaneous receivables Other Receivables, Net, Current Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Diluted (in shares) Shares for diluted net (loss) income per share (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] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Schedule of Other Current Assets Schedule of Other Current Assets [Table Text Block] Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Disposal Group Name [Domain] Disposal Group Name [Domain] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Borrowings under revolving credit facility Proceeds from Lines of Credit Property, plant and equipment, net Property, plant and equipment, net Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization DERIVATIVE FINANCIAL INSTRUMENTS Derivative Instruments and Hedging Activities Disclosure [Text Block] Net operating loss carryforwards Operating Loss Carryforwards Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Liability Derivatives Derivative Liability, Subject to Master Netting Arrangement, before Offset Decrease in other noncurrent assets Increase (Decrease) in Other Noncurrent Assets Net assets Disposal Group, Including Discontinued Operation, Assets (Liabilities), Net Disposal Group, Including Discontinued Operation, Assets (Liabilities), Net Gross profit Gross profit Gross Profit Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Weighted-average effect of dilutive equity awards outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted, Adjustment Stock Payments Stock Payments [Member] Stock Payments Less: accumulated depreciation, depletion, and amortization Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, Accumulated Depreciation and Amortization Total reassessments including interest Total Reassessment Amount Including Interest The estimated loss resulting from the income tax examination that has been reassessed as of the balance sheet date, including interest and penalties. Maximum period which the company hedges in advance of forecasted purchase Cash Flow Hedge, Hedging Exposure, Maximum Period Award Timing Predetermined Award Timing Predetermined [Flag] Treasury Stock Treasury Stock, Common [Member] Severance costs Severance Costs Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Total carrying value of debt and finance lease liabilities Debt and Lease Obligation Stock-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Quoted Prices in Active Market (Level One) Fair Value, Inputs, Level 1 [Member] Organization, Consolidation and Presentation of Financial Statements [Abstract] Changes in operating assets and liabilities: Increase (Decrease) in Other Operating Assets and Liabilities, Net [Abstract] Weighted-average fair value at beginning of period (in dollars per share) Weighted-average fair value at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value All Executive Categories All Executive Categories [Member] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Repayments of long-term lines of credit Repayments of Long-Term Lines of Credit Amortization of net pension costs, net of tax of $(0.1) for both the three months ended June 30, 2026 and June 30, 2025, respectively, and $(0.2) for both the nine months ended June 30, 2026 and June 30, 2025, respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax Other comprehensive (loss) income: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Asset Acquisition [Domain] Asset Acquisition [Domain] Scenario [Domain] Scenario [Domain] Weighted-average exercise price at beginning of period (in dollars per share) Weighted-average exercise price at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Asset impairment charge Tangible Asset Impairment Charges Operating lease right-of-use assets, net Operating Lease, Right-of-Use Asset STOCKHOLDERS’ EQUITY AND EQUITY INSTRUMENTS Shareholders' Equity and Share-Based Payments [Text Block] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Loss contingency liability, noncurrent Loss Contingency, Accrual, Noncurrent PSU at grant date (in shares per unit) Performance Stock Units At Grant Date The shares per unit related to attainment level of Performance Stock Units at grant date. Schedule of Computation of Basic and Diluted Net Income (Loss) Per Common Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] OPERATING SEGMENTS Segment Reporting [Text Block] Minimum Minimum [Member] Outstanding borrowing Long-Term Line of Credit Deposits Deposits Assets, Noncurrent Canadian Tax Authority Canada Revenue Agency [Member] Expiration Date Trading Arrangement Expiration Date Mutual fund investments in a non-qualified savings plan Investments, Fair Value Disclosure Hedging Relationship [Axis] Hedging Relationship [Axis] Schedule of Disaggregation of Revenue Schedule of Disaggregated Revenue by Product Type Disaggregation of Revenue [Table Text Block] Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Location, Statement of Income, Balance [Axis] Location, Statement of Income, Balance [Axis] 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] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Disposal Group, Including Discontinued Operations [Line Items] Disposal Group, Including Discontinued Operations [Line Items] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Number of business utilizing excavated areas Number Of Business Utilizing Excavated Areas Number Of Business Utilizing Excavated Areas Revolving accounts receivable financing facility Financing Receivable, Revolving Exercise Price Award Exercise Price Related Party Transaction [Axis] Related Party Transaction [Axis] Segment Reporting [Line Items] Segment Reporting [Line Items] Estimated insurance recoveries Estimated Insurance Recoveries Document Quarterly Report Document Quarterly Report Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] 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 and cash equivalents, beginning of the year Cash and cash equivalents, end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Required prepayment of term loan Repayments of Long-Term Debt Scenario [Axis] Scenario [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Debt issuance costs Debt Issuance Costs, Net Unamortized deferred financing costs Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Amount of security posted in the form of a performance bond Amount Of Security Posted In The Form Of A Performance Bond The estimated loss resulting from the income tax examination, including interest and penalties, that has been posted as security in the form of a performance bond in connection with the dispute. Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Secured Debt Secured Debt [Member] Adoption Date Trading Arrangement Adoption Date Common Stock, Large Cap US Companies Common stock, Large Cap US Companies [Member] Common stock, Large Cap US Companies [Member] Gross proceeds received Disposal Group, Including Discontinued Operation, Consideration Stated interest rate Debt Instrument, Interest Rate, Stated Percentage Total stockholders’ equity Beginning Balance Ending Balance Equity, Attributable to Parent Deferred financing costs written off Deferred Debt Issuance Cost, Writeoff Disposal Group, Disposed of by Sale, Not Discontinued Operations Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] Production recall expense Production Recall Expense Production Recall Expense 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 Reissued share of treasury stock (in shares) Reissued Shares Of Treasury Stock Related To The Exercise Of Stock Options This element is related to shares of treasury stocks reissued. Accrued expenses and other current liabilities Other Liabilities, Current [Abstract] Accounting Policies [Abstract] Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Risk-free rate of return Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Lease liability Operating Lease, Liability Loss on impairments Loss on impairments Intangible Asset, Including Goodwill, Impairment Loss Insider Trading Policies and Procedures [Line Items] Outstanding at beginning of period (in shares) Outstanding at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Finance lease liabilities Finance Lease, Liability Other, net Proceeds from (Payment for) Other Financing Activity Allowance for credit losses and rebates Accounts Receivable, Allowance for Credit Loss, Current Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Deferred income taxes Deferred Income Tax Expense (Benefit) Selling, general and administrative expenses Selling, General and Administrative Expense SUPPLEMENTAL BALANCE SHEET INFORMATION Supplemental Balance Sheet Disclosures [Text Block] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Business Combination [Domain] Business Combination [Domain] Letter of Credit Letter of Credit [Member] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Anti-dilutive weighted options outstanding (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount RSUs Restricted Stock Units (RSUs) [Member] Entity Central Index Key Entity Central Index Key Additional paid-in capital Additional Paid in Capital, Common Stock All Adjustments to Compensation All Adjustments to Compensation [Member] Corporate & Other Segment Reporting, Reconciling Item, Corporate Nonsegment [Member] Business Combination [Axis] Business Combination [Axis] 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] 0.08 Senior Notes due July 2030 Senior Notes July 2030 [Member] Senior Notes July 2030 Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Payments for legal settlements Payments for Legal Settlements Income Statement [Abstract] Income Statement [Abstract] Working capital adjustments Disposal Group Including Discontinued Operation, Working Capital Adjustments Disposal Group Including Discontinued Operation, Working Capital Adjustments Document Transition Report Document Transition Report Raw materials and supplies, net of allowance Inventory, Raw Materials And Supplies, Noncurrent, Net Of Reserves Inventory, Raw Materials And Supplies, Noncurrent, Net Of Reserves Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Derivatives Designated as Hedging Instruments Designated as Hedging Instrument [Member] Percent of forecasted usage to be hedged Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage Finance lease liabilities, net of current portion Finance Lease, Liability, Noncurrent Intersegment Eliminations Intersegment Eliminations [Member] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Number Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] City Area Code City Area Code Purchases of Property, plant and equipment in Accounts payable Purchases Of Property, Plant And Equipment In Accounts Payable Purchases Of Property, Plant And Equipment In Accounts Payable Income Tax Disclosure [Line Items] Income Tax Examination [Line Items] Property, plant and equipment, gross Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, before Accumulated Depreciation and Amortization Accumulated Other Comprehensive Loss Total AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Debt fair value amount Debt Instrument, Fair Value Disclosure Name Forgone Recovery, Individual Name Finished goods Inventory, Finished Goods, Net of Reserves Share-based payment arrangement, nonvested award, cost not yet recognized, period for recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Equity Awards Equity Awards [Member] Equity Awards Other Other Accrued Liabilities, Noncurrent Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Weighted-average fair value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Definitive-lived intangible assets Finite-Lived Intangible Assets, Fair Value Disclosure Statement [Line Items] Statement [Line Items] Total assets Total assets (as of end of period) Assets Notional amount (in MMBtus) Derivative, Nonmonetary Notional Amount, Energy Measure Number of weeks for grant Share-Based Compensation Arrangement, By Share-Based Payment, Number Of Weeks For Grant Share-Based Compensation Arrangement, By Share-Based Payment, Number Of Weeks For Grant Other noncurrent liabilities Other Liabilities, Noncurrent [Abstract] Net cash expense in product cost Interest Expense, Operating Mineral interests Mining Properties and Mineral Rights [Member] Mutual Fund Investments, Concentration Risk Mutual Fund Investments, Concentration Risk [Member] Mutual Fund Investments, Concentration Risk [Member] Operating Segments Operating Segments [Member] Interest expense Interest Expense, Nonoperating Purchases of Property, plant and equipment in Accrued expenses and other current liabilities Purchases Of Property, Plant And Equipment In Accrued Expenses And Other Current Liabilities Purchases Of Property, Plant And Equipment In Accrued Expenses And Other Current Liabilities Other assets Increase (Decrease) in Other Operating Assets PEO PEO [Member] Other Accrual for Taxes Other than Income Taxes, Current Weighted-average exercise price, cancelled/expired (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Share-based payment arrangement, expense Share-Based Payment Arrangement, Expense Other noncurrent liabilities Total other noncurrent liabilities Other Liabilities, Noncurrent Goodwill Goodwill 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 Amount of security posted in the form of cash Amount Of Security Posted In The Form Of Cash The estimated loss resulting from the income tax examination, including interest and penalties, that has been posted as security in the form of cash in connection with the dispute. Weighted-average fair value, granted (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Revenue recognized Contract with Customer, Liability, Revenue Recognized NOL Carryforwards Expire Beginning In 2031 NOL Carryforwards Expire Beginning In 2031 [Member] NOL Carryforwards Expire Beginning In 2031 Noncurrent portion of operating lease liabilities Operating Lease, Liability, Noncurrent Retained Earnings (Accumulated Deficit) Retained Earnings [Member] Revolving Credit Facility Revolving Credit Facility [Member] Weighted-average fair value, cancelled/expired (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Payment for costs related to sale Payment For Disposal Related Costs Payment For Disposal Related Costs Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Award Timing Disclosures [Line Items] Foreign Currency Accumulated Foreign Currency Adjustment Attributable to Parent [Member] 2023 Credit Agreement 2023 Credit Agreement [Member] 2023 Credit Agreement Diluted net (loss) income per common share (in dollars per share) Earnings Per Share, Diluted Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Entity Current Reporting Status Entity Current Reporting Status Other Contract Other Contract [Member] Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Fair value of stock withheld related to vesting of RSUs and PSUs Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Liability Class: Liabilities, Fair Value Disclosure [Abstract] Cash Flow Hedging Cash Flow Hedging [Member] Other noncurrent assets Other Assets, Noncurrent [Abstract] Litigation Case [Domain] Litigation Case [Domain] Shipping and handling cost Shipping and Handling [Member] Adjustments to reconcile net income (loss) to net cash flows provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Sales Total sales Sales to external customers Revenue from Contract with Customer, Excluding Assessed Tax Availability under revolving credit facility Line of Credit Facility, Remaining Borrowing Capacity Principal payments on long-term debt Repayments of Other Long-Term Debt Financial Instruments [Domain] Financial Instruments [Domain] Derivatives – natural gas instruments, net Derivative Asset INVENTORIES Inventory Disclosure [Text Block] Intangible Asset, Finite-Lived, Class [Axis] Intangible Asset, Finite-Lived, Class [Axis] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Share-based compensation arrangement by share-based payment award, non-option equity instruments, granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted Underlying Securities Award Underlying Securities Amount REVENUES Revenue from Contract with Customer [Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Deferred Stock Unit Deferred Stock Unit [Member] Deferred Stock Unit Accounts Receivable Securitization Facility Accounts Receivable Securitization Facility [Member] Accounts Receivable Securitization Facility Construction in progress Construction in Progress [Member] Raw materials and supplies Inventory, Raw Materials and Supplies, Net of Reserves Other, net Payment for 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