Inventories, Net - Inventories, Net (Detail) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Inventory [Line Items]
Raw materials	$ 105.7	$ 136.4
Work in process	44.9	48.5
Finished products	218.2	273.5
Supplies (chemicals)	79.2	79.8
Total	448.0	538.2
Chemicals
Inventory [Line Items]
Raw materials	100.7	133.2
Work in process	29.8	36.8
Finished products	214.7	270.0
Component Products
Inventory [Line Items]
Raw materials	5.0	3.2
Work in process	15.1	11.7
Finished products	$ 3.5	$ 3.5

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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