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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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Segment Information (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Results of Operations
Revenues									$ 1,311,917	$ 1,343,135	$ 1,263,089
Less: Inter-segment revenues									1,311,917	1,343,135	1,263,089
Gross profit	$ 34,099	$ 27,303	$ 30,005	$ 34,584	$ 40,404	$ 2,632	$ 15,955	$ 28,379	125,991	87,370	136,473
Operating income (loss)	14,499	$ 6,347	$ 4,935	$ 15,101	18,374	$ (14,448)	$ (3,671)	$ 8,547	40,882	8,802	58,607
Segment assets	564,967				561,689				564,967	561,689	568,932
Capital expenditures									13,939	15,773	23,589
Depreciation and amortization									21,441	23,480	18,518
Electrical Infrastructure [Member]
Results of Operations
Revenues									349,011	257,930	205,570
Less: Inter-segment revenues									349,011	257,930	205,570
Gross profit									29,301	(31,444)	20,629
Operating income (loss)									11,144	(44,293)	7,703
Segment assets	135,298				129,725				135,298	129,725	120,264
Capital expenditures									1,611	579	9,055
Depreciation and amortization									5,008	4,915	3,292
Oil Gas & Chemical [Member]
Results of Operations
Revenues									249,795	305,360	239,690
Less: Inter-segment revenues									249,795	305,360	239,690
Gross profit									18,553	25,394	26,912
Operating income (loss)									(3,503)	7,064	9,939
Segment assets	91,350				108,960				91,350	108,960	72,406
Capital expenditures									1,481	3,858	5,421
Depreciation and amortization									4,811	4,772	3,768
Storage Solutions [Member]
Results of Operations
Gross profit									67,843	58,085	68,448
Operating income (loss)									33,449	29,069	34,310
Segment assets	201,875				172,857				201,875	172,857	200,493
Capital expenditures									3,882	2,396	2,519
Depreciation and amortization									8,124	7,298	7,707
Industrial [Member]
Results of Operations
Gross profit									10,294	35,335	20,484
Operating income (loss)									(208)	16,962	6,655
Segment assets	67,569				102,761				67,569	102,761	105,049
Capital expenditures									104	1,139	1,157
Depreciation and amortization									3,498	6,495	3,751
Unallocated Corporate [Member]
Results of Operations
Segment assets	$ 68,875				$ 47,386				68,875	47,386	70,720
Capital expenditures									6,861	7,801	5,437
Gross [Member]
Results of Operations
Revenues									1,316,466	1,354,230	1,264,460
Less: Inter-segment revenues									1,316,466	1,354,230	1,264,460
Gross [Member] \| Electrical Infrastructure [Member]
Results of Operations
Revenues									349,011	257,930	205,570
Less: Inter-segment revenues									349,011	257,930	205,570
Gross [Member] \| Oil Gas & Chemical [Member]
Results of Operations
Revenues									252,973	310,826	240,131
Less: Inter-segment revenues									252,973	310,826	240,131
Gross [Member] \| Storage Solutions [Member]
Results of Operations
Revenues									564,738	504,155	611,826
Less: Inter-segment revenues									564,738	504,155	611,826
Gross [Member] \| Industrial [Member]
Results of Operations
Revenues									149,744	281,319	206,933
Less: Inter-segment revenues									149,744	281,319	206,933
Industrial [Member]
Results of Operations
Revenues									149,599	276,722	206,933
Less: Inter-segment revenues									149,599	276,722	206,933
Storage Solutions [Member]
Results of Operations
Revenues									563,512	503,123	610,896
Less: Inter-segment revenues									563,512	503,123	610,896
Intersegment Eliminations [Member]
Results of Operations
Revenues									4,549	11,095	1,371
Less: Inter-segment revenues									4,549	11,095	1,371
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									3,178	5,466	441
Less: Inter-segment revenues									3,178	5,466	441
Intersegment Eliminations [Member] \| Storage Solutions [Member]
Results of Operations
Revenues									1,226	1,032	930
Less: Inter-segment revenues									1,226	1,032	930
Intersegment Eliminations [Member] \| Industrial [Member]
Results of Operations
Revenues									145	4,597	0
Less: Inter-segment revenues									$ 145	$ 4,597	$ 0