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Goodwill and Other Intangible Assets Schedule of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Goodwill [Line Items]
Goodwill, Gross			$ 1,088,487	$ 1,081,452	$ 1,084,064
Goodwill, Accumulated Impairment Loss			(810,872)	(810,872)	(784,053)
Goodwill			277,615	270,580	300,011
Goodwill, Period Increase (Decrease)			7,035	(2,612)
Goodwill, Impairment Loss				(26,819)
Metal Cutting [Member]
Goodwill [Line Items]
Goodwill, Gross			455,276	448,241	450,853
Goodwill, Accumulated Impairment Loss			177,661	177,661	150,842
Goodwill			277,615	270,580	300,011
Goodwill, Period Increase (Decrease)			7,035	(2,612)
Goodwill, Impairment Loss				26,819
WIDIA [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss	$ (13,700)	$ (13,100)
Infrastructure [Member]
Goodwill [Line Items]
Goodwill, Gross			633,211	633,211	633,211
Goodwill, Accumulated Impairment Loss			633,211	633,211	633,211
Goodwill			0	0	$ 0
Goodwill, Period Increase (Decrease)			$ 0	$ 0