Concentration of Risk and Enterprise-Wide Disclosures (Details) $ in Thousands	12 Months Ended
Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) customer	Dec. 31, 2022 USD ($) customer
Concentration Risk [Line Items]
Allowance for credit losses	$ (555)	$ (361)
Contract revenues	$ 796,394	$ 711,778	$ 748,322
Foreign
Concentration Risk [Line Items]
Contract revenues, percent	7.40%	5.10%	0.90%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 142,492	$ 143,634
Allowance for credit losses	(555)	(361)
Net receivables	$ 141,937	$ 143,273
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
Contract revenues	$ 796,394	$ 711,778	$ 748,322
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	$ 19,874	$ 8,885
Concentration risk, percentage	14.00%	6.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables \| US Navy
Concentration Risk [Line Items]
Contract revenues, percent	11.10%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 234,175	$ 153,410	$ 80,116
Concentration risk, percentage	30.00%	22.00%	11.00%
Customer concentration risk \| Federal Government \| Contract revenues \| US Navy
Concentration Risk [Line Items]
Contract revenues, percent	25.00%	12.70%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 9,553	$ 2,355
Concentration risk, percentage	7.00%	2.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 74,286	$ 59,354	$ 62,516
Concentration risk, percentage	9.00%	8.00%	8.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 24,641	$ 12,804
Concentration risk, percentage	17.00%	9.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 123,160	$ 99,621	$ 125,015
Concentration risk, percentage	15.00%	14.00%	17.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 88,424	$ 119,590
Number of customers exceeding the 10% benchmark percentage \| customer		1
Concentration risk, percentage	62.00%	83.00%
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	$ 364,773	$ 399,393	$ 480,675
Concentration risk, percentage	46.00%	56.00%	64.00%

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