Basis of Presentation and Summary of Significant Accounting Policies - Components of Inventories (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Inventory Net [Abstract]
Raw materials and manufacturing supplies	$ 147.3	$ 139.4
Work in process	64.8	64.6
Finished goods	107.9	116.4
LIFO reserve	(17.9)	(18.6)
Total	$ 302.1	$ 301.8

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)(1))
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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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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.

+ References

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-Publisher FASB
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-Section 45
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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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