Inventories, Net - Inventories, Net (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Inventory [Line Items]
Raw materials	$ 137.7	$ 127.3
Work in process	62.2	50.8
Finished products	251.3	274.3
Supplies (chemicals)	73.0	69.7
Total	524.2	522.1
Chemicals
Inventory [Line Items]
Raw materials	134.3	124.4
Work in process	50.0	39.0
Finished products	247.6	270.7
Component Products
Inventory [Line Items]
Raw materials	3.4	2.9
Work in process	12.2	11.8
Finished products	$ 3.7	$ 3.6

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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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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