Contracts Revenue, Percent

No definition available.

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- Definition

Trade Accounts Receivable and Contract Receivable Retainage, Net

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

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- Definition

Amount of revenue earned from products sold or services provided under the terms of a contract, including, but not limited to, government contracts and construction contracts, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Concentration of Risk and Enterprise Wide Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Concentration Risk [Line Items]
Contract revenues	$ 162,214	$ 140,162	$ 137,420	$ 138,757	$ 144,295	$ 164,017	$ 140,301	$ 129,623	$ 578,553	$ 578,236	$ 466,498
Foreign
Concentration Risk [Line Items]
Contract revenues, percent									1.60%	1.30%	4.10%
Customer concentration risk \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Trade and retainage receivables	124,142				132,403				$ 124,142	$ 132,403
Concentration risk, percentage									100.00%	100.00%
Customer concentration risk \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage									100.00%	100.00%	100.00%
Contract revenues									$ 578,553	$ 578,236	$ 466,498
Customer concentration risk \| Federal Government \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Trade and retainage receivables	3,509				5,542				$ 3,509	$ 5,542
Concentration risk, percentage									3.00%	4.00%
Customer concentration risk \| Federal Government \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage									11.00%	7.00%	10.00%
Contract revenues									$ 63,823	$ 40,361	$ 45,439
Customer concentration risk \| State Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Trade and retainage receivables	4,503				9,302				$ 4,503	$ 9,302
Concentration risk, percentage									3.00%	7.00%
Customer concentration risk \| State Governments \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage									7.00%	7.00%	9.00%
Contract revenues									$ 42,613	$ 37,700	$ 42,026
Customer concentration risk \| Local Governments \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Trade and retainage receivables	18,256				20,886				$ 18,256	$ 20,886
Concentration risk, percentage									15.00%	16.00%
Customer concentration risk \| Local Governments \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage									16.00%	16.00%	28.00%
Contract revenues									$ 91,592	$ 94,461	$ 130,187
Customer concentration risk \| Private Companies \| Trade and contract retainage receivables
Concentration Risk [Line Items]
Trade and retainage receivables	$ 97,874				$ 96,673				$ 97,874	$ 96,673
Concentration risk, percentage									79.00%	73.00%
Customer concentration risk \| Private Companies \| Contract revenues
Concentration Risk [Line Items]
Concentration risk, percentage									66.00%	70.00%	53.00%
Contract revenues									$ 380,525	$ 405,714	$ 248,846