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Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Revenue (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Jun. 30, 2022
Revenue, Performance Obligation [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 542,700		$ 542,700
Performance obligations to be recognized as revenue within next twelve months	432,700		432,700
Contract with Customer, Asset and Liability [Abstract]
Costs and estimated earnings in excess of billings on uncompleted contracts	53,398		53,398		$ 44,752
Change in CIE			8,646
Billings on uncompleted contracts in excess of costs and estimated earnings	(114,729)		(114,729)		(65,106)
Change in BIE			(49,623)
Contract with customer, current liability, net	(61,331)		(61,331)		(20,354)
Change in net contract balances			(40,977)
Contract with Customer, Liability, Revenue Recognized			57,000
Disclosure Customer Contracts Additional Information [Abstract]
Construction Contractor, Receivable, Retainage, Year One	18,900		18,900		16,100
Construction Contractor, Receivable, Retainage, after Year One	7,800		7,800		$ 4,000
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	186,895	$ 177,003	589,166	$ 507,061
Process and Industrial Facilities
Disaggregation of Revenue [Line Items]
Loss on Contracts	3,300	4,800	12,700
Utility and Power Infrastructure
Disaggregation of Revenue [Line Items]
Loss on Contracts		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	96,755	100,602	311,511	303,508
Time-and-materials Contract
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	90,140	76,401	277,655	203,553
United States
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	178,261	160,453	524,731	459,654
Canada
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	6,932	16,268	52,742	45,038
Other international
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	$ 1,702	$ 282	$ 11,693	$ 2,369