Segment Information - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Jun. 30, 2015
Segment Reporting Information [Line Items]
Gross revenues	$ 310,172	$ 318,321	$ 956,568	$ 985,814
Consolidated revenues	309,422	314,155	952,282	978,718
Gross profit	27,303	2,632	91,892	46,966
Operating income	6,347	(14,448)	26,383	(9,572)
Segment assets	549,642		549,642		$ 561,689
Goodwill	78,845		78,845		71,518
Electrical Infrastructure [Member]
Segment Reporting Information [Line Items]
Gross revenues	94,414	48,228	251,437	162,434
Consolidated revenues	94,414	48,228	251,437	162,434
Gross profit	10,407	(22,429)	19,136	(38,976)
Operating income	4,948	(24,306)	5,425	(46,484)
Segment assets	135,305		135,305		129,725
Goodwill	42,134		42,134		42,374
Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	56,251	97,612	188,682	228,230
Consolidated revenues	55,729	95,758	185,580	224,574
Gross profit	2,616	7,261	14,270	18,999
Operating income	(1,964)	2,563	(3,577)	5,823
Segment assets	99,007		99,007		108,960
Goodwill	14,008		14,008		14,008
Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	132,857	107,640	400,074	370,977
Consolidated revenues	132,629	107,163	399,034	370,259
Gross profit	15,108	11,247	49,766	39,996
Operating income	6,382	5,055	24,305	18,785
Segment assets	193,218		193,218		172,857
Goodwill	17,276		17,276		9,664
Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	26,650	64,841	116,375	224,173
Consolidated revenues	26,650	63,006	116,231	221,451
Gross profit	(828)	6,553	8,720	26,947
Operating income	(3,019)	2,240	230	12,304
Segment assets	56,183		56,183		102,761
Goodwill	5,427		5,427		5,472
Other Segments [Member]
Segment Reporting Information [Line Items]
Segment assets	65,929		65,929		$ 47,386
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Gross revenues	750	4,166	4,286	7,096
Intersegment Eliminations [Member] \| Electrical Infrastructure [Member]
Segment Reporting Information [Line Items]
Gross revenues	0	0	0	0
Intersegment Eliminations [Member] \| Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	522	1,854	3,102	3,656
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	228	477	1,040	718
Intersegment Eliminations [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	$ 0	$ 1,835	$ 144	$ 2,722

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.18)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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