Share-Based Compensation - Schedule of Share-Based Compensation of PSU Activity (Details) - PSUs - Suncoke LTPEP	6 Months Ended
Jun. 30, 2025 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSUs, shares (in shares) \| shares	112,856
PSUs, weighted average grant date fair value per unit (in dollars per share) \| $ / shares	$ 9.22
Pre-Tax Return of Capital for Coke and Coal Logistics Businesses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of award allocation	50.00%
Measurement period	3 years
TSR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement period	3 years
TSR \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement results payout percentage	80.00%
TSR \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement results payout percentage	120.00%

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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