Segment Information - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016
Segment Reporting Information [Line Items]
Gross revenues	$ 348,230	$ 320,489
Consolidated revenues	341,781	319,331
Gross profit	32,278	34,584
Operating income	14,301	15,101
Segment assets	569,223		$ 564,967
Goodwill	78,274		78,293
Electrical Infrastructure [Member]
Segment Reporting Information [Line Items]
Gross revenues	88,025	65,625
Consolidated revenues	88,025	65,625
Gross profit	5,250	4,708
Operating income	1,057	1,200
Segment assets	143,699		135,298
Goodwill	42,078		42,170
Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	37,828	68,959
Consolidated revenues	32,542	68,311
Gross profit	1	5,683
Operating income	(2,905)	1,416
Segment assets	78,474		91,350
Goodwill	14,008		14,008
Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	199,650	144,570
Consolidated revenues	199,522	144,236
Gross profit	26,453	20,232
Operating income	16,773	11,549
Segment assets	238,205		201,875
Goodwill	16,771		16,681
Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	22,727	41,335
Consolidated revenues	21,692	41,159
Gross profit	574	3,961
Operating income	(624)	936
Segment assets	61,826		67,569
Goodwill	5,417		5,434
Other Segments [Member]
Segment Reporting Information [Line Items]
Segment assets	47,019		$ 68,875
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Gross revenues	6,449	1,158
Intersegment Eliminations [Member] \| Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	5,286	648
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	128	334
Intersegment Eliminations [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	$ 1,035	$ 176

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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