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Restructuring and Related Charges - Restructuring Accrual (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Restructuring Reserve [Abstract]
Beginning Balance			$ 29,806
Restructuring Charges	$ 1,100	$ 7,100	6,664	$ 44,500
Asset Write-Down			(4,096)
Translation			1,697
Cash Expenditures			(21,739)
Ending Balance	12,332		12,332
Industrial [Member]
Restructuring Reserve [Abstract]
Beginning Balance			17,733
Restructuring Charges			4,859
Asset Write-Down			(3,084)
Translation			1,174
Cash Expenditures			(15,137)
Ending Balance	5,545		5,545
Industrial [Member] \| Severance [Member]
Restructuring Reserve [Abstract]
Beginning Balance			17,639
Restructuring Charges			1,804
Asset Write-Down			0
Translation			1,171
Cash Expenditures			(15,099)
Ending Balance	5,515		5,515
Industrial [Member] \| Facilities [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			3,084
Asset Write-Down			(3,084)
Translation			0
Cash Expenditures			0
Ending Balance	0		0
Industrial [Member] \| Other Restructuring [Member]
Restructuring Reserve [Abstract]
Beginning Balance			94
Restructuring Charges			(29)
Asset Write-Down			0
Translation			3
Cash Expenditures			(38)
Ending Balance	30		30
WIDIA [Member]
Restructuring Reserve [Abstract]
Beginning Balance			2,434
Restructuring Charges			1,125
Asset Write-Down			(747)
Translation			250
Cash Expenditures			(3,059)
Ending Balance	3		3
WIDIA [Member] \| Severance [Member]
Restructuring Reserve [Abstract]
Beginning Balance			2,434
Restructuring Charges			384
Asset Write-Down			0
Translation			249
Cash Expenditures			(3,067)
Ending Balance	0		0
WIDIA [Member] \| Facilities [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			747
Asset Write-Down			(747)
Translation			0
Cash Expenditures			0
Ending Balance	0		0
WIDIA [Member] \| Other Restructuring [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			(6)
Asset Write-Down			0
Translation			1
Cash Expenditures			8
Ending Balance	3		3
Infrastructure [Member]
Restructuring Reserve [Abstract]
Beginning Balance			9,639
Restructuring Charges			680
Asset Write-Down			(265)
Translation			273
Cash Expenditures			(3,543)
Ending Balance	6,784		6,784
Infrastructure [Member] \| Severance [Member]
Restructuring Reserve [Abstract]
Beginning Balance			9,573
Restructuring Charges			422
Asset Write-Down			0
Translation			273
Cash Expenditures			(3,501)
Ending Balance	6,767		6,767
Infrastructure [Member] \| Facilities [Member]
Restructuring Reserve [Abstract]
Beginning Balance			21
Restructuring Charges			265
Asset Write-Down			(265)
Translation			0
Cash Expenditures			(21)
Ending Balance	0		0
Infrastructure [Member] \| Other Restructuring [Member]
Restructuring Reserve [Abstract]
Beginning Balance			45
Restructuring Charges			(7)
Asset Write-Down			0
Translation			0
Cash Expenditures			(21)
Ending Balance	$ 17		$ 17