Concentration of Risk and Enterprise-Wide Disclosures (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) customer	Dec. 31, 2021 USD ($) customer	Dec. 31, 2020 USD ($) customer
Concentration Risk [Line Items]
Allowance for credit losses	$ (606)	$ (323)
Contract revenues	$ 748,322	$ 601,360	$ 709,942
Foreign
Concentration Risk [Line Items]
Contract revenues, percent	0.90%	0.50%	1.80%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 158,237	$ 129,875
Allowance for credit losses	(606)	(323)
Net receivables	$ 157,631	$ 129,552
Number of customers exceeding the 10% benchmark percentage \| customer	0	0
Concentration risk, percentage	100.00%	100.00%
Customer concentration risk \| Contract revenues
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer	0	0
Contract revenues	$ 748,322	$ 601,360	$ 709,942
Concentration risk, percentage	100.00%	100.00%	100.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 4,612	$ 6,563
Concentration risk, percentage	3.00%	5.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 80,116	$ 54,480	$ 51,793
Concentration risk, percentage	11.00%	9.00%	7.00%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 3,111	$ 61
Concentration risk, percentage	2.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 62,516	$ 4,790	$ 27,574
Concentration risk, percentage	8.00%	1.00%	4.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 16,197	$ 11,923
Concentration risk, percentage	10.00%	9.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer			1
Contract revenues	$ 125,015	$ 120,311	$ 202,839
Concentration risk, percentage	17.00%	20.00%	29.00%
Customer concentration risk \| Local Governments \| Contract revenues \| Customer One
Concentration Risk [Line Items]
Concentration risk, percentage			11.40%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 134,317	$ 111,328
Concentration risk, percentage	85.00%	86.00%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 480,675	$ 421,779	$ 427,736
Concentration risk, percentage	64.00%	70.00%	60.00%

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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