Business Segment Information - Schedule of Segment Assets (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Segment Reporting Information [Line Items]
Total assets	$ 1,932.0	$ 1,668.2
Domestic
Segment Reporting Information [Line Items]
Total assets	1,810.9	1,658.0
International
Segment Reporting Information [Line Items]
Total assets	121.1	10.2
Operating Segments
Segment Reporting Information [Line Items]
Total assets	1,860.0	1,509.3
Operating Segments \| Domestic Coke
Segment Reporting Information [Line Items]
Total assets	1,300.9	1,351.1
Operating Segments \| Industrial Services
Segment Reporting Information [Line Items]
Total assets	559.1	158.2
Corporate and Other
Segment Reporting Information [Line Items]
Total assets	$ 72.0	$ 158.9

Amount of asset recognized for present right to economic benefit.

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+ Details

SunCoke Energy, Inc. 10-Q