Inventories, Net - Inventories, Net (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Inventory [Line Items]
Raw materials	$ 120.5	$ 95.8
Work in process	40.9	34.6
Finished products	227.3	320.9
Supplies (Chemicals)	65.8	64.5
Total	454.5	515.8
Chemicals
Inventory [Line Items]
Raw materials	117.2	93.1
Work in process	29.0	23.5
Finished products	223.7	317.6
Component Products
Inventory [Line Items]
Raw materials	3.3	2.7
Work in process	11.9	11.1
Finished products	$ 3.6	$ 3.3

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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