Segment Information - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Jun. 30, 2016
Segment Reporting Information [Line Items]
Gross revenues	$ 252,259	$ 310,172	$ 914,513	$ 956,568
Revenues	251,237	309,422	905,673	952,282
Gross profit	(2,614)	27,303	57,876	91,892
Operating income	(21,210)	6,347	1,328	26,383
Segment assets	580,268		580,268		$ 564,967
Goodwill	113,182		113,182		78,293
Electrical Infrastructure [Member]
Segment Reporting Information [Line Items]
Gross revenues	82,032	94,414	273,215	251,437
Revenues	82,032	94,414	273,215	251,437
Gross profit	(13,371)	10,407	(896)	19,136
Operating income	(16,306)	4,948	(13,085)	5,425
Segment assets	167,280		167,280		135,298
Goodwill	41,995		41,995		42,170
Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	69,295	56,251	164,036	188,682
Revenues	68,888	55,729	157,144	185,580
Gross profit	4,333	2,616	6,765	14,270
Operating income	(2,199)	(1,964)	(7,054)	(3,577)
Segment assets	142,551		142,551		91,350
Goodwill	42,747		42,747		14,008
Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	74,431	132,857	403,008	400,074
Revenues	74,052	132,629	402,331	399,034
Gross profit	5,456	15,108	48,980	49,766
Operating income	(1,552)	6,382	23,463	24,305
Segment assets	169,829		169,829		201,875
Goodwill	16,730		16,730		16,681
Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	26,501	26,650	74,254	116,375
Revenues	26,265	26,650	72,983	116,231
Gross profit	968	(828)	3,027	8,720
Operating income	(1,153)	(3,019)	(1,996)	230
Segment assets	45,623		45,623		67,569
Goodwill	11,710		11,710		5,434
Other Segments [Member]
Segment Reporting Information [Line Items]
Segment assets	54,985		54,985		$ 68,875
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Gross revenues	1,022	750	8,840	4,286
Intersegment Eliminations [Member] \| Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	407	522	6,892	3,102
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	379	228	677	1,040
Intersegment Eliminations [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	$ 236	$ 0	$ 1,271	$ 144

Gross revenues before intersegment eliminations

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