Contracts Revenue, Percent

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- Definition

Number of customers exceeding the 10% benchmark percentage.

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No definition available.

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- Definition

Trade Accounts Receivable and Contract Receivable Retainage, Gross

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No definition available.

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- Definition

Trade Accounts Receivable and Contract Receivable Retainage, Net

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No definition available.

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- Definition

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

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- Definition

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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No definition available.

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- Definition

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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- Definition

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, 2021 USD ($) customer	Mar. 31, 2020 USD ($) customer	Dec. 31, 2020 USD ($) customer
Concentration Risk [Line Items]
Allowance for credit losses	$ (323)		$ (411)
Contract revenues	$ 153,309	$ 166,620
Foreign
Concentration Risk [Line Items]
Contract revenues, percent	1.60%	2.40%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 130,919		133,265
Allowance for credit losses	(323)		(411)
Net receivables	$ 130,596		$ 132,854
Number of customers exceeding the 10% benchmark percentage \| customer			0
Concentration risk, percentage	99.00%		100.00%
Customer concentration risk \| Contract revenues
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer	0	0
Contract revenues	$ 153,309	$ 166,620
Contract revenues, percent	100.00%	100.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 4,341		$ 4,826
Concentration risk, percentage	3.00%		4.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 12,764	$ 5,319
Contract revenues, percent	8.00%	3.00%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 220
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	168	$ 12,232
Contract revenues, percent		7.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 22,444		$ 17,823
Concentration risk, percentage	17.00%		13.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 33,516	$ 52,012
Contract revenues, percent	22.00%	31.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 103,914		$ 110,616
Number of customers exceeding the 10% benchmark percentage \| customer	1
Concentration risk, percentage	79.00%		83.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables \| Customer One
Concentration Risk [Line Items]
Contract revenues, percent	10.60%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 106,861	$ 97,057
Contract revenues, percent	70.00%	59.00%