Concentration of Risk and Enterprise Wide Disclosures (Tables)

6 Months Ended

Jun. 30, 2013

Accounts receivable

Concentration Risk [Line Items]

Schedules of concentration of risk, by risk factor

The table below presents the concentrations of receivables (trade and retainage) at June 30, 2013 and December 31, 2012, respectively:

	June 30, 2013				December 31, 2012
Federal Government	$	10,246	26	%	$	7,375	14	%
State Governments	—		—	%	1,761		3	%
Local Governments	4,671		12	%	5,532		10	%
Private Companies	24,534		62	%	38,617		73	%
Total receivables	$	39,451	100	%	$	53,285	100	%

Contract revenues

Concentration Risk [Line Items]

Schedules of concentration of risk, by risk factor

Additionally, the table below represents concentrations of revenue by type of customer for the three and six months ended June 30, 2013, and 2012.

	Three months ended June 30,								Six months ended June 30,
	2013		%		2012		%		2013		%		2012		%
Federal	$	16,544	19	%	$	12,212	18	%	$	36,493	23	%	$	24,928	21	%
State	5,797		7	%	9,494		14	%	12,016		8	%	17,014		14	%
Local	13,065		16	%	13,478		20	%	26,186		16	%	24,594		21	%
Private	48,675		58	%	31,948		48	%	84,445		53	%	51,486		44	%
	$	84,081	100	%	$	67,132	100	%	$	159,140	100	%	$	118,022	100	%