Debt and Financing Obligations (Revolving Facility) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Outstanding balance	$ 500.0	$ 543.8
Revolving credit facility \| Line of Credit \| SunCoke Revolving Credit Facility, Due 2024
Debt Instrument [Line Items]
Remaining borrowing capacity	$ 350.0
Unused capacity commitment fee	0.175%
The weighted-average interest rate for borrowings outstanding under credit agreement (as a percent)	6.50%
Revolving credit facility \| Line of Credit \| SunCoke Revolving Credit Facility, Due 2024 \| SOFR
Debt Instrument [Line Items]
Basis spread on variable rate	0.10%
Revolving credit facility \| Line of Credit \| SunCoke Revolving Credit Facility, Due 2024 \| Secured Overnight Financing Rate (SOFR) Floor
Debt Instrument [Line Items]
Basis spread on variable rate	0.00%
Revolving credit facility \| Line of Credit \| SunCoke Revolving Credit Facility, Due 2024 \| Adjusted Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Revolving credit facility \| Line of Credit \| SunCoke Revolving Credit Facility, Due 2024 \| Adjusted Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Letter of Credit \| Line of Credit \| SunCoke Revolving Credit Facility, Due 2024
Debt Instrument [Line Items]
Outstanding balance	$ 21.7

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

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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- Definition

Weighted average interest rate of debt outstanding.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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