Inventories, Net - Schedule of Inventories Net (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Finished products	$ 643.6	$ 615.7
Products in process	41.9	35.6
Raw materials	32.4	31.3
Supplies and expendable parts	141.5	139.6
Inventories, Gross	859.4	822.2
Less: Allowances	(168.6)	(159.2)
Total	$ 690.8	$ 663.0

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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