Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Results of Operations
Gross revenues									$ 1,107,560	$ 1,421,276	$ 1,097,738
Revenue	$ 195,837	$ 248,327	$ 318,677	$ 338,097	$ 398,714	$ 358,887	$ 340,568	$ 318,511	1,100,938	1,416,680	1,091,553
Gross profit (loss)	19,233	20,477	30,001	32,465	43,738	36,906	27,886	23,421	102,176	131,951	91,936
Intangible asset impairments and restructuring costs	7,451	6,559	38,515	0					52,525	0	17,998
Operating income (loss)	(7,920)	$ (5,800)	$ (31,679)	$ 8,774	17,389	$ 12,794	$ 5,527	$ 2,220	(36,625)	37,930	(10,479)
Segment assets	517,310				633,394				517,310	633,394	558,033
Capital expenditures									18,539	19,558	8,711
Depreciation and amortization expense									19,124	18,224	20,347
Electrical Infrastructure [Member]
Results of Operations
Gross revenues									112,890	217,417	255,931
Revenue									112,890	217,417	255,931
Gross profit (loss)									(1,105)	15,470	18,300
Intangible asset impairments and restructuring costs									27,855	0	17,281
Operating income (loss)									(36,503)	3,668	(16,531)
Segment assets	96,010				155,880				96,010	155,880	161,207
Capital expenditures									2,141	2,493	493
Depreciation and amortization expense									2,108	2,460	4,359
Oil Gas & Chemical [Member]
Results of Operations
Gross revenues									203,404	322,065	324,546
Revenue									200,950	319,867	322,772
Gross profit (loss)									15,822	35,987	33,423
Intangible asset impairments and restructuring costs									3,850	0	717
Operating income (loss)									(7,328)	12,984	8,798
Segment assets	74,041				91,959				74,041	91,959	111,064
Capital expenditures									1,580	2,736	1,514
Depreciation and amortization expense									5,465	4,661	5,904
Storage Solutions [Member]
Results of Operations
Gross revenues									562,439	524,330	319,106
Revenue									559,199	521,932	314,696
Gross profit (loss)									71,934	56,011	25,778
Intangible asset impairments and restructuring costs									1,296	0	0
Operating income (loss)									27,306	14,097	(5,907)
Segment assets	203,291				188,912				203,291	188,912	149,695
Capital expenditures									8,394	4,644	3,346
Depreciation and amortization expense									7,492	6,666	6,623
Industrial [Member]
Results of Operations
Gross revenues									228,827	357,464	198,155
Revenue									227,899	357,464	198,154
Gross profit (loss)									15,525	24,483	14,435
Intangible asset impairments and restructuring costs									19,524	0	0
Operating income (loss)									(20,100)	7,181	3,161
Segment assets	19,957				90,336				19,957	90,336	58,816
Capital expenditures									3,600	3,464	0
Depreciation and amortization expense									4,059	4,437	3,461
Unallocated Corporate [Member]
Results of Operations
Segment assets	$ 124,011				$ 106,307				124,011	106,307	77,251
Capital expenditures									2,824	6,221	3,358
Intersegment Eliminations [Member]
Results of Operations
Gross revenues									6,622	4,596	6,185
Intersegment Eliminations [Member] | Electrical Infrastructure [Member]
Results of Operations
Gross revenues									0	0	0
Intersegment Eliminations [Member] | Oil Gas & Chemical [Member]
Results of Operations
Gross revenues									2,454	2,198	1,774
Intersegment Eliminations [Member] | Storage Solutions [Member]
Results of Operations
Gross revenues									3,240	2,398	4,410
Intersegment Eliminations [Member] | Industrial [Member]
Results of Operations
Gross revenues									$ 928	$ 0	$ 1