Segment Information - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017
Segment Reporting Information [Line Items]
Gross revenues	$ 270,675	$ 348,230
Revenues	269,910	341,781
Gross profit	28,891	32,278
Operating income	7,321	14,301
Segment assets	572,454		$ 586,030
Goodwill	113,860		113,501
Electrical Infrastructure [Member]
Segment Reporting Information [Line Items]
Gross revenues	79,971	88,025
Revenues	79,971	88,025
Gross profit	8,267	5,250
Operating income	3,577	1,057
Segment assets	186,094		183,351
Goodwill	42,386		42,152
Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	85,861	37,828
Revenues	85,653	32,542
Gross profit	11,038	1
Operating income	4,134	(2,905)
Segment assets	137,631		129,177
Goodwill	33,604		33,604
Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	71,572	199,650
Revenues	71,015	199,522
Gross profit	7,540	26,453
Operating income	(75)	16,773
Segment assets	143,648		166,742
Goodwill	16,845		16,764
Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	33,271	22,727
Revenues	33,271	21,692
Gross profit	2,046	574
Operating income	(315)	(624)
Segment assets	61,748		53,754
Goodwill	21,025		20,981
Other Segments [Member]
Segment Reporting Information [Line Items]
Segment assets	43,333		$ 53,006
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Gross revenues	765	6,449
Intersegment Eliminations [Member] \| Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	208	5,286
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	557	128
Intersegment Eliminations [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	$ 0	$ 1,035

Gross revenues before intersegment eliminations

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+ References

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