Inventories, Net - Inventories, Net (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Inventory [Line Items]
Raw materials	$ 92.0	$ 109.6
Work in process	43.7	30.6
Finished products	229.7	195.0
Supplies (chemicals)	64.0	63.2
Total	429.4	398.4
Chemicals
Inventory [Line Items]
Raw materials	89.3	106.9
Work in process	33.1	20.8
Finished products	226.4	192.2
Component Products
Inventory [Line Items]
Raw materials	2.7	2.7
Work in process	10.6	9.8
Finished products	$ 3.3	$ 2.8

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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