Debt - Covenants (Narrative) (Details) - Credit Agreement and Partner Revolver $ in Millions	Jun. 30, 2026 USD ($)
Line of Credit Facility [Line Items]
Maximum consolidated leverage ratio	4.50
Minimum consolidated interest coverage ratio	2.50
SunCoke Energy Partners, L.P.
Line of Credit Facility [Line Items]
Cross default covenant threshold	$ 50.0

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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+ Details