Business Segment Information - Schedule of Segment Assets (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Segment Reporting Information [Line Items]
Total assets	$ 1,641.4	$ 1,668.2
Operating Segments
Segment Reporting Information [Line Items]
Total assets	1,480.1	1,519.5
Operating Segments \| Domestic Coke
Segment Reporting Information [Line Items]
Total assets	1,306.8	1,351.1
Operating Segments \| Logistics
Segment Reporting Information [Line Items]
Total assets	160.4	158.2
Operating Segments \| Brazil Coke
Segment Reporting Information [Line Items]
Total assets	12.9	10.2
Corporate and Other
Segment Reporting Information [Line Items]
Total assets	$ 161.3	$ 148.7

Amount of asset recognized for present right to economic benefit.

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+ Details