Accounts and other receivables, net - Components of Accounts and Other Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Trade accounts receivable:
VAT and other receivables	$ 45.9	$ 33.4
Allowance for doubtful accounts	(3.9)	(4.2)
Total	325.7	321.1
Trade Accounts Receivable | Kronos
Trade accounts receivable:
Trade Accounts receivable	269.2	273.6
Trade Accounts Receivable | CompX
Trade accounts receivable:
Trade Accounts receivable	14.2	17.1
Trade Accounts Receivable | BMI/LandWell
Trade accounts receivable:
Trade Accounts receivable	$ 0.3	$ 1.2