Segment Data - Sales and Operating Income (Loss) by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2018
Segment Reporting Information [Line Items]
Assets	$ 2,531,108		$ 2,531,108		$ 2,925,737
External sales:
Sales (Note 3)	587,394	$ 571,345	1,174,080	$ 1,113,799
Operating income (loss):
Total operating (income) loss	(78,858)	(63,641)	(162,010)	(115,812)
Interest expense	8,104	7,231	16,201	14,379
Other income, net	(4,022)	(3,220)	(6,782)	(7,437)
Income from continuing operations before income taxes	74,776	59,630	152,591	108,870
Industrial [Member]
External sales:
Sales (Note 3)	317,320	312,448	637,878	609,912
Operating income (loss):
Total operating (income) loss	(57,519)	(40,504)	(116,061)	(72,543)
Infrastructure [Member]
External sales:
Sales (Note 3)	221,120	211,153	438,576	410,900
Operating income (loss):
Total operating (income) loss	(20,614)	(23,833)	(44,474)	(44,223)
WIDIA [Member]
External sales:
Sales (Note 3)	48,954	47,744	97,626	92,987
Operating income (loss):
Total operating (income) loss	(1,728)	(474)	(3,822)	(154)
Corporate [Member]
Operating income (loss):
Total operating (income) loss	$ 1,003	$ 1,170	$ 2,347	$ 1,108