Supplemental Balance Sheet Information - Inventory (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Jun. 30, 2019
Inventory, Net [Abstract]
Raw materials and supplies	$ 213.7	$ 161.6
Work-in-process	108.2	115.0
Total inventories, gross	321.9	276.6
Inventory cost adjustment	(24.7)	(19.4)
Inventories	$ 297.2	$ 257.2

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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount of valuation reserve for inventory.

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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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