Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Carrying value of goodwill by segment
Net Goodwill	$ 113,501	$ 78,293	$ 71,518
Acquisition Related Adjustment for Final Working Capital Settlement		88
Goodwill resulting from purchase		35,146	6,942
Goodwill impairment	(17,281)
Translation adjustment	(58)	(26)	(167)
Net Goodwill	96,162	113,501	78,293
Electrical Infrastructure [Member]
Carrying value of goodwill by segment
Net Goodwill	42,152	42,170	42,374
Acquisition Related Adjustment for Final Working Capital Settlement		0
Goodwill resulting from purchase		0	0
Goodwill impairment	(17,281)
Translation adjustment	(45)	(18)	(204)
Net Goodwill	24,826	42,152	42,170
Oil Gas & Chemical [Member]
Carrying value of goodwill by segment
Net Goodwill	33,604	14,008	14,008
Acquisition Related Adjustment for Final Working Capital Settlement		0
Goodwill resulting from purchase		19,596	0
Goodwill impairment	0
Translation adjustment	0	0	0
Net Goodwill	33,604	33,604	14,008
Storage Solutions [Member]
Carrying value of goodwill by segment
Net Goodwill	16,764	16,681	9,664
Acquisition Related Adjustment for Final Working Capital Settlement		88
Goodwill resulting from purchase		0	6,942
Goodwill impairment	0
Translation adjustment	(4)	(5)	75
Net Goodwill	16,760	16,764	16,681
Industrial [Member]
Carrying value of goodwill by segment
Net Goodwill	20,981	5,434	5,472
Acquisition Related Adjustment for Final Working Capital Settlement		0
Goodwill resulting from purchase		15,550	0
Goodwill impairment	0
Translation adjustment	(9)	(3)	(38)
Net Goodwill	$ 20,972	$ 20,981	$ 5,434

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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