Share-Based Compensation - Performance Share Units (Details) - PSUs - Suncoke LTPEP	9 Months Ended
Sep. 30, 2023 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares) \| shares	147,232
Weighted Average Per Share Grant Date Fair Value (in dollars per share) \| $ / shares	$ 9.84
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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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