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, 2020	Jun. 30, 2019
Goodwill [Line Items]
Goodwill and Intangible Asset Impairment	$ 15,600	$ 14,600
Goodwill [Roll Forward]
Gross goodwill	1,079,530		$ 1,079,530	$ 1,084,064
Accumulated impairment losses	(810,872)		(810,872)	(784,053)
Goodwill, Beginning Balance			300,011
Change in gross goodwill due to translation			(4,534)
Impairment charges			(26,819)
Goodwill, Ending Balance	268,658		268,658
Industrial [Member]
Goodwill [Roll Forward]
Gross goodwill	405,862		405,862	409,912
Accumulated impairment losses	(137,204)		(137,204)	(137,204)
Goodwill, Beginning Balance			272,708
Change in gross goodwill due to translation			(4,050)
Impairment charges			0
Goodwill, Ending Balance	268,658		268,658
Infrastructure [Member]
Goodwill [Roll Forward]
Gross goodwill	633,211		633,211	633,211
Accumulated impairment losses	(633,211)		(633,211)	(633,211)
Goodwill, Beginning Balance			0
Change in gross goodwill due to translation			0
Impairment charges			0
Goodwill, Ending Balance	0		0
WIDIA [Member]
Goodwill [Roll Forward]
Gross goodwill	40,457		40,457	40,941
Accumulated impairment losses	(40,457)		(40,457)	$ (13,638)
Goodwill, Beginning Balance			27,303
Change in gross goodwill due to translation			(484)
Impairment charges	(13,700)	$ (13,100)	26,819
Goodwill, Ending Balance	$ 0		$ 0

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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