Concentration of Risk and Enterprise-Wide Disclosures (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($) customer	Dec. 31, 2022 USD ($) customer	Dec. 31, 2021 USD ($) customer
Concentration Risk [Line Items]
Allowance for credit losses	$ (361)	$ (606)
Contract revenues	$ 711,778	$ 748,322	$ 601,360
Foreign
Concentration Risk [Line Items]
Contract revenues, percent	5.10%	0.90%	0.50%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 143,634	$ 158,237
Allowance for credit losses	(361)	(606)
Net receivables	$ 143,273	$ 157,631
Number of customers exceeding the 10% benchmark percentage \| customer		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	$ 711,778	$ 748,322	$ 601,360
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	$ 8,885	$ 4,612
Concentration risk, percentage	6.00%	3.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer	1
Contract revenues	$ 153,410	$ 80,116	$ 54,480
Concentration risk, percentage	22.00%	11.00%	9.00%
Customer concentration risk \| Federal Government \| Contract revenues \| Customer One
Concentration Risk [Line Items]
Contract revenues, percent	12.70%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 2,355	$ 3,111
Concentration risk, percentage	2.00%	2.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 59,354	$ 62,516	$ 4,790
Concentration risk, percentage	8.00%	8.00%	1.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 12,804	$ 16,197
Concentration risk, percentage	9.00%	10.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 99,621	$ 125,015	$ 120,311
Concentration risk, percentage	14.00%	17.00%	20.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 119,590	$ 134,317
Number of customers exceeding the 10% benchmark percentage \| customer	1
Concentration risk, percentage	83.00%	85.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables \| Customer One
Concentration Risk [Line Items]
Contract revenues, percent	19.90%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 399,393	$ 480,675	$ 421,779
Concentration risk, percentage	56.00%	64.00%	70.00%

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