Inventories, Net - Inventories, Net (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventory [Line Items]
Raw materials	$ 105.3	$ 95.8
Work in process	41.0	34.6
Finished products	303.1	320.9
Supplies (chemicals)	65.7	64.5
Total	515.1	515.8
Chemicals
Inventory [Line Items]
Raw materials	102.0	93.1
Work in process	29.2	23.5
Finished products	299.7	317.6
Component Products
Inventory [Line Items]
Raw materials	3.3	2.7
Work in process	11.8	11.1
Finished products	$ 3.4	$ 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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