Business combinations, dispositions and related transactions - Summary of Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Business combinations, dispositions and related transactions
Current assets	$ 1,259.1	$ 1,453.7
Property and equipment, net	751.6	723.4	$ 517.3
Total assets	2,632.3	2,800.2
Other liabilities, primarily current	1.4	17.1
Total liabilities and equity	2,632.3	2,800.2
Net sales	2,136.1	2,166.6	1,977.1
Cost of sales	1,781.6	1,680.3	1,676.5
General and administrative	312.3	256.2	277.4
Total costs and other expense	2,179.1	1,922.4	1,996.6
Net income (loss)	$ (54.9)	$ 161.3	$ 5.1