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Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Revenue (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Jun. 30, 2021
Revenue, Performance Obligation [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 433,600		$ 433,600
Performance obligations to be recognized as revenue within next twelve months	368,900		368,900
Contract with Customer, Asset and Liability [Abstract]
Costs and estimated earnings in excess of billings on uncompleted contracts	46,393		46,393		$ 30,774
Change in CIE			15,619
Billings on uncompleted contracts in excess of costs and estimated earnings	(73,868)		(73,868)		(53,832)
Change in BIE			(20,036)
Contract with customer, current liability, net	(27,475)		(27,475)		(23,058)
Change in net contract balances			(4,417)
Contract with Customer, Liability, Revenue Recognized			48,200
Disclosure Customer Contracts Additional Information [Abstract]
Construction Contractor, Receivable, Retainage, Year One	14,100		14,100		19,900
Construction Contractor, Receivable, Retainage, after Year One	2,800		2,800		$ 3,100
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	177,003	$ 148,260	507,061	$ 498,499
Process and Industrial Facilities
Disaggregation of Revenue [Line Items]
Loss on Contracts	4,800
Utility and Power Infrastructure
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	800		(5,100)
Storage and Terminal Solutions
Disaggregation of Revenue [Line Items]
Loss on Contracts			5,500
Fixed-price Contract
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	100,602	96,412	303,508	343,639
Time-and-materials Contract
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	76,401	51,848	203,553	154,860
United States
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	160,453	138,001	459,654	445,578
Canada
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	16,268	8,930	45,038	47,673
Other international
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	$ 282	$ 1,329	$ 2,369	$ 5,248