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Authorized 50,000,000 shares; no issued shares at both June 30, 2026 and December 31, 2025 Preferred Stock, Value, Issued Short-term financing lease liability Business Combination, Recognized Liabilities Assumed, Finance Leases, Lease Liabilities, Current Business Combination, Recognized Liabilities Assumed, Finance Leases, Lease Liabilities, Current Adjustment to Compensation: Adjustment to Compensation [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Name Measure Name Income Taxes Income Tax Disclosure [Text Block] Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Corporate and Other Corporate Segment and Other Operating Segment [Member] Purchase consideration Business Combination, Consideration Transferred Additional Paid-In Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Name Trading Arrangement, Individual Name Cost of products sold and other expenses Cost Of Products Sold And Other Expenses Cost Of Products Sold And Other Expenses Cash and cash equivalents Cash and Cash Equivalent Company Selected Measure Amount Company Selected Measure Amount Income tax receivable Income Taxes Receivable Depreciation and amortization expense Depreciation, Depletion and Amortization Entity Address, Address Line Two Entity Address, Address Line Two SunCoke Energy Partners, L.P. SunCoke Energy Partners, L.P. [Member] SunCoke Energy Partners, L.P. Share issuances, net of shares withheld for taxes (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Net income Net income Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 4.875 percent senior notes, due 2029 (“2029 Senior Notes”) Senior Notes, Due 2029 [Member] Senior Notes, Due 2029 Total revenue Business Combination, Pro Forma Information, Pro Forma Revenue Non-PEO NEO Non-PEO NEO [Member] Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Income tax expense Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] Net decrease in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Current portion of black lung liability Loss Contingency, Accrual, Current Deferred income taxes Business Combination, Recognized Liability Assumed, Deferred Tax Liability Net income attributable to SunCoke Energy, Inc. Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Debt issuance costs Unamortized Debt Issuance Expense Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Business Combination, Pro Forma Information, Nonrecurring Adjustment, Tax Expense (Benefit) Business Combination, Pro Forma Information, Nonrecurring Adjustment, Tax Expense (Benefit) [Member] Business Combination, Pro Forma Information, Nonrecurring Adjustment, Tax Expense (Benefit) Interest income Investment Income, Interest Schedule of Estimated Fixed Fee and Take-Or-Pay Revenue Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Right-of-use assets Business Combination, Recognized Identifiable Assets Acquired, Right-Of-Use Assets Business Combination, Recognized Identifiable Assets Acquired, Right-Of-Use Assets Other Other Products And Services [Member] Other Products and Services [Member] Business Combination, Pro Forma Information, Nonrecurring Adjustment, Elimination of Debt and Associated Interest Expense Business Combination, Pro Forma Information, Nonrecurring Adjustment, Elimination Of Debt And Associated Interest Expense [Member] Business Combination, Pro Forma Information, Nonrecurring Adjustment, Elimination Of Debt And Associated Interest Expense Increase (decrease) to property, plants, and equipment Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment Revenues Revenues [Abstract] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]