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Trade Accounts Receivable and Contract Receivable Retainage, Gross

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Trade Accounts Receivable and Contract Receivable Retainage, Net

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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Concentration of Risk and Enterprise-Wide Disclosures (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) customer	Mar. 31, 2023 USD ($) customer	Dec. 31, 2023 USD ($) customer
Concentration Risk [Line Items]
Allowance for credit losses	$ (366)		$ (361)
Contract revenues	160,672	$ 159,174
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	128,561		143,634
Allowance for credit losses	(366)		(361)
Net receivables	$ 128,195		$ 143,273
Concentration risk, percentage	100.00%		100.00%
Customer concentration risk \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 160,672	$ 159,174
Concentration risk, percentage	100.00%	100.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 15,048		$ 8,885
Concentration risk, percentage	12.00%		6.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 53,382	$ 23,056
Concentration risk, percentage	33.00%	14.00%
Customer concentration risk \| Federal Government \| Contract revenues \| US Navy
Concentration Risk [Line Items]
Concentration risk, percentage	23.70%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 4,577		$ 2,355
Concentration risk, percentage	4.00%		2.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 13,984	$ 18,328
Concentration risk, percentage	9.00%	12.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 17,358		$ 12,804
Concentration risk, percentage	13.00%		9.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 28,973	$ 20,688
Concentration risk, percentage	18.00%	13.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 91,578		$ 119,590
Number of customers exceeding the 10% benchmark percentage \| customer	1		1
Concentration risk, percentage	71.00%		83.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables \| Customer One
Concentration Risk [Line Items]
Concentration risk, percentage	14.90%		19.90%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer		1
Contract revenues	$ 64,333	$ 97,102
Concentration risk, percentage	40.00%	61.00%
Customer concentration risk \| Private Companies \| Contract revenues \| Customer One
Concentration Risk [Line Items]
Concentration risk, percentage		10.90%
Geographic concentration \| Contract revenues \| Foreign
Concentration Risk [Line Items]
Concentration risk, percentage	6.00%	1.70%