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Restructuring and Related Charges - Restructuring Accrual (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Restructuring Reserve [Abstract]
Beginning Balance			$ 17,639
Restructuring Charges	$ 1,500	$ 100	2,620	$ 5,600
Asset Write-Down			257
Translation			(234)
Cash Expenditures			(6,476)
Ending Balance	13,806		13,806
Industrial [Member]
Restructuring Reserve [Abstract]
Beginning Balance			7,967
Restructuring Charges			1,572
Asset Write-Down			9
Translation			(129)
Cash Expenditures			(3,558)
Ending Balance	5,861		5,861
Industrial [Member] \| Severance [Member]
Restructuring Reserve [Abstract]
Beginning Balance			7,967
Restructuring Charges			1,552
Asset Write-Down			0
Translation			(128)
Cash Expenditures			(3,568)
Ending Balance	5,823		5,823
Industrial [Member] \| Facilities [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			(9)
Asset Write-Down			9
Translation			0
Cash Expenditures			0
Ending Balance	0		0
Industrial [Member] \| Other Restructuring [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			29
Asset Write-Down			0
Translation			(1)
Cash Expenditures			10
Ending Balance	38		38
WIDIA [Member]
Restructuring Reserve [Abstract]
Beginning Balance			2,102
Restructuring Charges			115
Asset Write-Down			0
Translation			(9)
Cash Expenditures			(260)
Ending Balance	1,948		1,948
WIDIA [Member] \| Severance [Member]
Restructuring Reserve [Abstract]
Beginning Balance			2,087
Restructuring Charges			113
Asset Write-Down			0
Translation			(9)
Cash Expenditures			(261)
Ending Balance	1,930		1,930
WIDIA [Member] \| Facilities [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			0
Asset Write-Down			0
Translation			0
Cash Expenditures			0
Ending Balance	0		0
WIDIA [Member] \| Other Restructuring [Member]
Restructuring Reserve [Abstract]
Beginning Balance			15
Restructuring Charges			2
Asset Write-Down			0
Translation			0
Cash Expenditures			1
Ending Balance	18		18
Infrastructure [Member]
Restructuring Reserve [Abstract]
Beginning Balance			7,570
Restructuring Charges			933
Asset Write-Down			248
Translation			(96)
Cash Expenditures			(2,658)
Ending Balance	5,997		5,997
Infrastructure [Member] \| Severance [Member]
Restructuring Reserve [Abstract]
Beginning Balance			7,558
Restructuring Charges			1,159
Asset Write-Down			0
Translation			(96)
Cash Expenditures			(2,665)
Ending Balance	5,956		5,956
Infrastructure [Member] \| Facilities [Member]
Restructuring Reserve [Abstract]
Beginning Balance			0
Restructuring Charges			(248)
Asset Write-Down			248
Translation			0
Cash Expenditures			0
Ending Balance	0		0
Infrastructure [Member] \| Other Restructuring [Member]
Restructuring Reserve [Abstract]
Beginning Balance			12
Restructuring Charges			22
Asset Write-Down			0
Translation			0
Cash Expenditures			7
Ending Balance	$ 41		$ 41