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

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Concentration of Risk and Enterprise-Wide Disclosures (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) customer	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Concentration Risk [Line Items]
Allowance for credit losses	$ (3,146)		$ (3,146)		$ (3,461)
Contract revenues	221,878	$ 205,286	438,179	$ 393,939
Contract revenues
Concentration Risk [Line Items]
Contract revenues	221,878	205,286	438,179	393,939
Federal Government
Concentration Risk [Line Items]
Contract revenues	40,113	39,429	69,839	81,313
State Governments
Concentration Risk [Line Items]
Contract revenues	36,886	36,322	72,544	65,283
Local Governments
Concentration Risk [Line Items]
Contract revenues	34,322	43,127	61,942	80,164
Private Companies
Concentration Risk [Line Items]
Contract revenues	110,557	$ 86,408	233,854	$ 167,179
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	174,833		174,833		228,350
Allowance for credit losses	(3,146)		(3,146)		(3,461)
Net receivables	$ 171,687		$ 171,687		$ 224,889
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
Concentration risk, percentage	100.00%	100.00%	100.00%	100.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 20,242		$ 20,242		$ 51,057
Concentration risk, percentage			12.00%		23.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables \| US Navy
Concentration Risk [Line Items]
Concentration risk, percentage					20.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage	18.00%	19.00%	16.00%	21.00%
Customer concentration risk \| Federal Government \| Contract revenues \| US Navy
Concentration Risk [Line Items]
Concentration risk, percentage		16.00%		17.00%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 19,918		$ 19,918		$ 14,008
Concentration risk, percentage			11.00%		6.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage	17.00%	18.00%	17.00%	17.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 24,766		$ 24,766		$ 23,453
Concentration risk, percentage			14.00%		10.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage	15.00%	21.00%	14.00%	20.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 109,907		$ 109,907		$ 139,832
Concentration risk, percentage			63.00%		61.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables \| US Navy
Concentration Risk [Line Items]
Concentration risk, percentage					12.00%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage	50.00%	42.00%	53.00%	42.00%