Restructuring And Related Cost, Number Of Power Production Facilities Closed

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Restructuring and Asset Impairment Charges - Narrative (Details) $ in Millions	3 Months Ended				9 Months Ended
	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 facility	Mar. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and asset impairment charges	$ 5.0			$ 0.0	$ 15.0	$ 2.3
Proceeds from disposals of property, plant and equipment and assets held for sale					1.6	0.3
Non-cash inventory write-downs from restructuring	2.6			$ 0.0	$ 2.6	$ 0.0
Performance Engineered Products
Restructuring Cost and Reserve [Line Items]
Asset impairment charges	4.9	$ 8.7
Severance costs	0.6	$ 1.3
Proceeds from disposals of property, plant and equipment and assets held for sale	$ 0.5
Fixed Cost Reduction
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated, period percent			20.00%
Facility Closing
Restructuring Cost and Reserve [Line Items]
Number of small domestic power metals production facilities closed \| facility			2