Goodwill and Other Intangible Assets - Carrying Amount of Goodwill Attributable to Each Segment (Details) - USD ($) $ in Thousands	9 Months Ended
	Mar. 31, 2019	Jun. 30, 2018
Goodwill [Roll Forward]
Goodwill	$ 1,082,332	$ 1,085,855
Accumulated impairment losses	(784,053)	(784,053)
Goodwill, Beginning Balance	301,802
Goodwill, Foreign Currency Translation Gain (Loss)	(3,523)
Goodwill, Ending Balance	298,279
Industrial [Member]
Goodwill [Roll Forward]
Goodwill	408,049	411,458
Accumulated impairment losses	(137,204)	(137,204)
Goodwill, Beginning Balance	274,254
Goodwill, Foreign Currency Translation Gain (Loss)	(3,409)
Goodwill, Ending Balance	270,845
Infrastructure [Member]
Goodwill [Roll Forward]
Goodwill	633,211	633,211
Accumulated impairment losses	(633,211)	(633,211)
Goodwill, Beginning Balance	0
Goodwill, Foreign Currency Translation Gain (Loss)	0
Goodwill, Ending Balance	0
WIDIA [Member]
Goodwill [Roll Forward]
Goodwill	41,072	41,186
Accumulated impairment losses	(13,638)	$ (13,638)
Goodwill, Beginning Balance	27,548
Goodwill, Foreign Currency Translation Gain (Loss)	(114)
Goodwill, Ending Balance	$ 27,434