Segment Data - Sales and Operating (Loss) Income by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Segment Reporting Information [Line Items]
Assets	$ 2,614,826		$ 2,614,826		$ 3,037,591
External sales:
Sales	440,507	$ 505,080	840,812	$ 1,023,168
Operating income (loss):
Total operating income (loss)	19,034	(47,638)	1,857	(31,261)
Interest expense	8,317	8,055	18,896	15,936
Other income, net	(3,857)	(4,211)	(7,875)	(6,891)
Income (loss) from continuing operations before income taxes	14,574	(51,482)	(9,164)	(40,306)
Infrastructure [Member]
External sales:
Sales	157,590	181,501	310,019	375,504
Operating income (loss):
Total operating income (loss)	(6,265)	11,570	(13,533)	14,260
Corporate [Member]
Operating income (loss):
Total operating income (loss)	924	891	1,743	1,131
Metal Cutting
External sales:
Sales	282,917	323,579	530,793	647,664
Operating income (loss):
Total operating income (loss)	$ (13,693)	$ 35,177	$ 9,933	$ 15,870