Supplemental Balance Sheet Information - Prepaid and Other Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Jun. 30, 2019
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid expenses	$ 33.1	$ 18.7
Contract with Customer, Asset, Net, Current	35.6	23.3
Spare parts supplies	23.1	8.1
Prepaid income tax	11.0	10.0
Non-U.S. value added tax	12.0	16.4
Other current assets	27.0	23.6
Prepaid expenses and other	$ 141.8	$ 100.1

Spare parts.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for income and other taxes that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities.

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