Concentration of Risk and Enterprise-Wide Disclosures (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($) customer	Mar. 31, 2021 USD ($) customer	Dec. 31, 2021 USD ($)
Concentration Risk [Line Items]
Allowance for credit losses	$ (323)		$ (323)
Contract revenues	$ 174,931	$ 153,309
Foreign
Concentration Risk [Line Items]
Contract revenues, percent	0.40%	1.60%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 143,570		129,875
Allowance for credit losses	(323)		(323)
Net receivables	$ 143,247		$ 129,552
Number of customers exceeding the 10% benchmark percentage \| customer	0	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
Contract revenues	$ 174,931	$ 153,309
Contract revenues, percent	100.00%	100.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 8,380		$ 6,563
Concentration risk, percentage	6.00%		5.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 22,695	$ 12,764
Contract revenues, percent	13.00%	8.00%
Customer concentration risk \| Federal Government \| Contract revenues \| Customer One
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer	1
Concentration risk, percentage	10.40%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 571		$ 61
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 7,704	$ 168
Contract revenues, percent	4.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 19,929		$ 11,923
Concentration risk, percentage	14.00%		9.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 32,402	$ 33,516
Contract revenues, percent	19.00%	22.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 114,690		$ 111,328
Concentration risk, percentage	80.00%		86.00%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 112,130	$ 106,861
Contract revenues, percent	64.00%	70.00%

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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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