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.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Segment Information (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Results of Operations
Revenues									$ 1,343,135	$ 1,263,089	$ 892,574
Less: Inter-segment revenues									1,343,135	1,263,089	892,574
Gross profit	$ 40,404	$ 2,632	$ 15,955	$ 28,379	$ 36,903	$ 39,944	$ 34,150	$ 25,476	87,370	136,473	94,702
Operating income (loss)	18,374	$ (14,448)	$ (3,671)	$ 8,547	14,209	$ 18,819	$ 14,817	$ 10,762	8,802	58,607	36,714
Segment assets	568,331				568,932				568,331	568,932	409,978
Capital expenditures									15,773	23,589	23,231
Depreciation and amortization									23,480	18,518	12,782
Electrical Infrastructure [Member]
Results of Operations
Revenues									257,930	205,570	171,204
Less: Inter-segment revenues									257,930	205,570	171,204
Gross profit									(31,444)	20,629	21,754
Operating income (loss)									(44,293)	7,703	11,185
Segment assets	129,725				120,264				129,725	120,264	64,771
Capital expenditures									579	9,055	2,129
Depreciation and amortization									4,915	3,292	2,167
Oil Gas & Chemical [Member]
Results of Operations
Revenues									305,360	239,690	273,848
Less: Inter-segment revenues									305,360	239,690	273,848
Gross profit									25,394	26,912	32,879
Operating income (loss)									7,064	9,939	15,415
Segment assets	108,960				72,406				108,960	72,406	75,591
Capital expenditures									3,858	5,421	2,942
Depreciation and amortization									4,772	3,768	2,943
Storage Solutions [Member]
Results of Operations
Gross profit									58,085	68,448	37,455
Operating income (loss)									29,069	34,310	11,904
Segment assets	172,857				200,493				172,857	200,493	159,149
Capital expenditures									2,396	2,519	9,929
Depreciation and amortization									7,298	7,707	6,740
Industrial [Member]
Results of Operations
Gross profit									35,335	20,484	2,614
Operating income (loss)									16,962	6,655	(1,790)
Segment assets	102,761				105,049				102,761	105,049	27,347
Capital expenditures									1,139	1,157	1,645
Depreciation and amortization									6,495	3,751	932
Unallocated Corporate [Member]
Results of Operations
Segment assets	$ 54,028				$ 70,720				54,028	70,720	83,120
Capital expenditures									7,801	5,437	6,586
Gross [Member]
Results of Operations
Revenues									1,354,230	1,264,460	895,298
Less: Inter-segment revenues									1,354,230	1,264,460	895,298
Gross [Member] \| Electrical Infrastructure [Member]
Results of Operations
Revenues									257,930	205,570	171,204
Less: Inter-segment revenues									257,930	205,570	171,204
Gross [Member] \| Oil Gas & Chemical [Member]
Results of Operations
Revenues									310,826	240,131	273,979
Less: Inter-segment revenues									310,826	240,131	273,979
Gross [Member] \| Storage Solutions [Member]
Results of Operations
Revenues									504,155	611,826	395,794
Less: Inter-segment revenues									504,155	611,826	395,794
Gross [Member] \| Industrial [Member]
Results of Operations
Revenues									281,319	206,933	54,321
Less: Inter-segment revenues									281,319	206,933	54,321
Industrial [Member]
Results of Operations
Revenues									276,722	206,933	54,321
Less: Inter-segment revenues									276,722	206,933	54,321
Storage Solutions [Member]
Results of Operations
Revenues									503,123	610,896	393,201
Less: Inter-segment revenues									503,123	610,896	393,201
Intersegment Eliminations [Member]
Results of Operations
Revenues									11,095	1,371	2,724
Less: Inter-segment revenues									11,095	1,371	2,724
Intersegment Eliminations [Member] \| Electrical Infrastructure [Member]
Results of Operations
Revenues									0	0	0
Less: Inter-segment revenues									0	0	0
Intersegment Eliminations [Member] \| Oil Gas & Chemical [Member]
Results of Operations
Revenues									5,466	441	131
Less: Inter-segment revenues									5,466	441	131
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Results of Operations
Revenues									1,032	930	2,593
Less: Inter-segment revenues									1,032	930	2,593
Intersegment Eliminations [Member] \| Industrial [Member]
Results of Operations
Revenues									4,597	0	0
Less: Inter-segment revenues									$ 4,597	$ 0	$ 0