Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019	May 31, 2021
Carrying value of goodwill by segment
Net Goodwill	$ 60,369	$ 93,368	$ 96,162
Goodwill impairment		(32,881)
Disposal of business			(2,775)
Translation adjustment	267	(118)	(19)
Net Goodwill	60,636	60,369	93,368
Goodwill attributable to reporting units at risk for impairment				$ 37,700
Utility and Power Infrastructure
Carrying value of goodwill by segment
Net Goodwill	6,905	31,840	31,848
Goodwill impairment		(24,900)
Disposal of business			0
Translation adjustment	79	(35)	(8)
Net Goodwill	6,984	6,905	31,840
Process and Industrial Facilities
Carrying value of goodwill by segment
Net Goodwill	26,846	34,842	37,612
Goodwill impairment		(7,981)
Disposal of business			(2,775)
Translation adjustment	32	(15)	5
Net Goodwill	26,878	26,846	34,842
Storage and Terminal Solutions Segment
Carrying value of goodwill by segment
Net Goodwill	26,618	26,686	26,702
Goodwill impairment		0
Disposal of business			0
Translation adjustment	156	(68)	(16)
Net Goodwill	$ 26,774	$ 26,618	$ 26,686

Goodwill attributable to reporting units at risk for impairment

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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 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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Amount of divestiture 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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