Inventories

3 Months Ended

Mar. 31, 2026

Inventory, Net [Abstract]

Inventories

9.    Inventories

Inventories consist of the following:

	March 31, 2026		December 31, 2025
Raw materials	$	166.0	$	161.5
Work-in-process	54.1		52.2
Finished goods	32.6		36.5
Operating and other supplies	259.4		269.4
Total inventories	$	512.1	$	519.6

Inventories are stated at the lower of cost or Net Realizable Value ("NRV") using the first-in, first-out or the weighted average cost method.