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		6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($) customer	Jun. 30, 2020 USD ($) customer	Jun. 30, 2021 USD ($) customer	Jun. 30, 2020 USD ($) customer	Dec. 31, 2020 USD ($) customer
Concentration Risk [Line Items]
Allowance for credit losses	$ (323)		$ (323)		$ (411)
Contract revenues	$ 145,875	$ 183,713	$ 299,184	$ 350,333
Foreign
Concentration Risk [Line Items]
Contract revenues, percent	0.20%	2.10%	0.90%	2.30%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 128,382		$ 128,382		133,265
Allowance for credit losses	(323)		(323)		(411)
Net receivables	$ 128,059		$ 128,059		$ 132,854
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		0	0
Contract revenues	$ 145,875	$ 183,713	$ 299,184	$ 350,333
Contract revenues, percent	99.00%	100.00%	99.00%	100.00%
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 6,392		$ 6,392		$ 4,826
Concentration risk, percentage			5.00%		4.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 12,345	$ 10,902	$ 25,109	$ 16,221
Contract revenues, percent	8.00%	6.00%	8.00%	4.00%
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 215		$ 215
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	246	$ 9,092	414	$ 21,324
Contract revenues, percent		5.00%		6.00%
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	15,170		$ 15,170		$ 17,823
Concentration risk, percentage			12.00%		13.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Number of customers exceeding the 10% benchmark percentage \| customer		1
Contract revenues	$ 38,576	$ 51,848	$ 72,092	$ 103,860
Contract revenues, percent	26.00%	28.00%	24.00%	30.00%
Customer concentration risk \| Local Governments \| Contract revenues \| Customer One
Concentration Risk [Line Items]
Concentration risk, percentage		10.10%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Gross receivables	$ 106,605		$ 106,605		$ 110,616
Number of customers exceeding the 10% benchmark percentage \| customer			1
Concentration risk, percentage			83.00%		83.00%
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables \| Customer One
Concentration Risk [Line Items]
Contract revenues, percent			10.20%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Contract revenues	$ 94,708	$ 111,871	$ 201,569	$ 208,928
Contract revenues, percent	65.00%	61.00%	67.00%	60.00%