Concentration of Risk and Enterprise Wide Disclosures (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended	1 Months Ended	3 Months Ended	6 Months Ended	1 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended			12 Months Ended	3 Months Ended		6 Months Ended			12 Months Ended	3 Months Ended		6 Months Ended			12 Months Ended	3 Months Ended		6 Months Ended			12 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Trade and Contract Retainage Receivables [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Contract Revenues [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] US Army Corps of Engineers [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] US Army Corps of Engineers [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] US Army Corps of Engineers [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] US Army Corps of Engineers [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] US Army Corps of Engineers [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Louisiana Department of Transportation [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Louisiana Department of Transportation [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Canaveral Port Authority [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Canaveral Port Authority [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Canaveral Port Authority [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Private Sector Customer [Member] Trade and Contract Retainage Receivables [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Private Sector Customer [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Private Sector Customer [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Private Sector Customer [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Private Sector Customer [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Federal Government [Member] Trade and Contract Retainage Receivables [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Federal Government [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Federal Government [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Federal Government [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Federal Government [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Federal Government [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] State Governments [Member] Trade and Contract Retainage Receivables [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] State Governments [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] State Governments [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] State Governments [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] State Governments [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] State Governments [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Local Governments [Member] Trade and Contract Retainage Receivables [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Local Governments [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Local Governments [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Local Governments [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Local Governments [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Local Governments [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Private Companies [Member] Trade and Contract Retainage Receivables [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Private Companies [Member] Trade and Contract Retainage Receivables [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Private Companies [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Private Companies [Member] Contract Revenues [Member]	Jun. 30, 2012 Customer Concentration Risk [Member] Private Companies [Member] Contract Revenues [Member]	Jun. 30, 2011 Customer Concentration Risk [Member] Private Companies [Member] Contract Revenues [Member]
Concentration Risk [Line Items]
Trade and retainage receivables						$ 40,960	$ 26,931																				$ 4,771	$ 5,958					$ 418	$ 379					$ 9,498	$ 6,207					$ 26,273	$ 14,387
Concentration risk, percentage						100.00%	100.00%	100.00%	100.00%	100.00%	100.00%	9.10%	10.60%	22.80%	15.30%	24.40%	13.30%	10.90%	18.20%	11.30%	9.90%	24.40%	12.50%	19.10%	13.20%	10.60%	12.00%	22.00%	18.00%	42.00%	21.00%	44.00%	1.00%	1.00%	14.00%	23.00%	14.00%	19.00%	23.00%	24.00%	20.00%	17.00%	21.00%	15.00%	64.00%	53.00%	48.00%	18.00%	44.00%	22.00%
Contract revenues	$ 67,132	$ 70,899	$ 118,022	$ 149,956	$ 67,132				$ 70,899	$ 118,022	$ 149,956																		$ 12,212	$ 29,869	$ 24,928	$ 66,514			$ 9,494	$ 16,054	$ 17,014	$ 27,641			$ 13,478	$ 12,044	$ 24,594	$ 22,139			$ 31,948	$ 12,932	$ 51,486	$ 33,662