Segment information - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Depreciation from reportable segments:
Total depreciation	$ 7.1	$ 10.1	$ 23.5	$ 34.0
Other
Depreciation from reportable segments:
Total depreciation	2.1	3.1	6.8	10.6
MCM Products | Operating Segments
Depreciation from reportable segments:
Total depreciation	4.7	4.7	13.8	16.0
All other segments | Operating Segments
Depreciation from reportable segments:
Total depreciation	$ 0.3	$ 2.3	$ 2.9	$ 7.4