Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2021
Revenue, Performance Obligation [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 396,800		$ 396,800
Performance obligations to be recognized as revenue within next twelve months	326,600		326,600
Contract with Customer, Asset and Liability [Abstract]
Costs and estimated earnings in excess of billings on uncompleted contracts	34,503		34,503		$ 30,774
Change in CIE			3,729
Billings on uncompleted contracts in excess of costs and estimated earnings	(84,859)		(84,859)		(53,832)
Change in BIE			(31,027)
Change in net contract balances			(27,298)
Contract with customer, current liability, net	(50,356)		(50,356)		(23,058)
Contract with Customer, Liability, Revenue Recognized			48,400
Disclosure Customer Contracts Additional Information [Abstract]
Construction Contractor, Receivable, Retainage, Year One	13,600		13,600		19,900
Construction Contractor, Receivable, Retainage, after Year One	2,100		2,100		$ 3,100
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	161,965	$ 167,468	330,058	$ 350,239
Utility and Power Infrastructure
Disaggregation of Revenue [Line Items]
Loss on Contracts			5,900
Storage and Terminal Solutions
Disaggregation of Revenue [Line Items]
Loss on Contracts	2,800		5,500
Fixed-price Contract
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	100,841	113,871	202,906	247,227
Time-and-materials Contract
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	61,124	53,597	127,152	103,012
United States
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	145,917	146,200	299,201	307,577
Canada
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	15,260	19,132	28,770	38,743
Other international
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer	$ 788	$ 2,136	$ 2,087	$ 3,919