Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill and Other Intangible Assets - Carrying Amount of Goodwill Attributable to Each Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2021	Jun. 30, 2020
Goodwill [Line Items]
Goodwill and Intangible Asset Impairment	$ 15,600	$ 14,600
Goodwill [Roll Forward]
Gross goodwill			$ 1,086,920	$ 1,081,452
Accumulated impairment losses			(810,872)	(810,872)
Goodwill, Beginning Balance			270,580
Change in gross goodwill due to translation			5,468
Goodwill, Ending Balance			276,048
Infrastructure [Member]
Goodwill [Roll Forward]
Gross goodwill			633,211	633,211
Accumulated impairment losses			(633,211)	(633,211)
Goodwill, Beginning Balance			0
Change in gross goodwill due to translation			0
Goodwill, Ending Balance			0
Metal Cutting
Goodwill [Roll Forward]
Gross goodwill			453,709	448,241
Accumulated impairment losses			(177,661)	$ (177,661)
Goodwill, Beginning Balance			270,580
Change in gross goodwill due to translation			5,468
Goodwill, Ending Balance			$ 276,048
WIDIA [Member]
Goodwill [Roll Forward]
Impairment charges	13,700	13,100
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 1,900	$ 1,500