Segment Information - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2015
Segment Reporting Information [Line Items]
Gross revenues	$ 325,907	$ 344,911	$ 646,396	$ 667,493
Consolidated revenues	323,529	342,880	642,860	664,563
Gross profit	30,005	15,955	64,589	44,334
Operating income	4,935	(3,671)	20,036	4,876
Segment assets	572,148		572,148		$ 561,689
Goodwill	70,605		70,605		71,518
Electrical Infrastructure [Member]
Segment Reporting Information [Line Items]
Gross revenues	91,398	58,533	157,023	114,206
Consolidated revenues	91,398	58,533	157,023	114,206
Gross profit	4,021	(16,058)	8,729	(16,547)
Operating income	(723)	(18,522)	477	(22,178)
Segment assets	148,447		148,447		129,725
Goodwill	41,779		41,779		42,374
Oil Gas & Chemical [Member]
Segment Reporting Information [Line Items]
Gross revenues	63,472	76,419	132,431	130,618
Consolidated revenues	61,540	75,457	129,851	128,816
Gross profit	5,971	7,352	11,654	11,738
Operating income	(3,029)	2,682	(1,613)	3,260
Segment assets	93,098		93,098		108,960
Goodwill	14,008		14,008		14,008
Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	122,647	129,987	267,217	263,337
Consolidated revenues	122,169	129,805	266,405	263,096
Gross profit	14,426	14,231	34,658	28,749
Operating income	6,374	6,627	17,923	13,730
Segment assets	182,587		182,587		172,857
Goodwill	9,458		9,458		9,664
Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	48,390	79,972	89,725	159,332
Consolidated revenues	48,422	79,085	89,581	158,445
Gross profit	5,587	10,430	9,548	20,394
Operating income	2,313	5,542	3,249	10,064
Segment assets	77,287		77,287		102,761
Goodwill	5,360		5,360		5,472
Other Segments [Member]
Segment Reporting Information [Line Items]
Segment assets	70,729		70,729		$ 47,386
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Gross revenues	2,378	2,031	3,536	2,930
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	1,932	962	2,580	1,802
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Segment Reporting Information [Line Items]
Gross revenues	478	182	812	241
Intersegment Eliminations [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Gross revenues	$ (32)	$ 887	$ 144	$ 887

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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