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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		12 Months Ended
	Mar. 31, 2026 USD ($) customer	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Concentration Risk [Line Items]
Allowance for credit losses	$ (3,443)		$ (3,461)
Contract revenues	216,301	$ 188,653
Contract revenues
Concentration Risk [Line Items]
Contract revenues	216,301	188,653
Federal Government
Concentration Risk [Line Items]
Contract revenues	29,726	41,884
State Governments
Concentration Risk [Line Items]
Contract revenues	35,658	28,961
Local Governments
Concentration Risk [Line Items]
Contract revenues	27,620	37,037
Private Companies
Concentration Risk [Line Items]
Contract revenues	123,297	$ 80,771
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	198,057		228,350
Allowance for credit losses	(3,443)		(3,461)
Net receivables	$ 194,614		$ 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%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 19,882		$ 51,057
Concentration risk, percentage	10.00%		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	14.00%	22.00%
Customer concentration risk \| Federal Government \| Contract revenues \| US Navy
Concentration Risk [Line Items]
Concentration risk, percentage		18.00%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 21,436		$ 14,008
Concentration risk, percentage	11.00%		6.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage	16.00%	15.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 28,398		$ 23,453
Concentration risk, percentage	14.00%		10.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage	13.00%	20.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 128,341		$ 139,832
Concentration risk, percentage	65.00%		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	57.00%	43.00%