Concentration of Risk and Enterprise Wide Disclosures (Tables)

3 Months Ended

Mar. 31, 2020

Trade and contract retainage receivables

Concentration Risk [Line Items]

Schedules of concentration of risk, by risk factor

	March 31, 2020				December 31, 2019
Federal Government	$	1,340	1	%	$	4,765	3	%
State Governments		3,703	2	%		5,864	4	%
Local Governments		31,094	21	%		41,944	26	%
Private Companies		111,624	76	%		109,114	67	%
Gross receivables		147,761	100	%		161,687	100	%
Allowance for credit losses		(3,011)				(2,600)
Net receivables	$	144,750			$	159,087

Contract revenues

Concentration Risk [Line Items]

Schedules of concentration of risk, by risk factor

	Three months ended March 31,
	2020		%		2019		%
Federal Government	$	5,319	3	%	$	10,277	7	%
State Governments		12,232	7	%		4,055	3	%
Local Government		52,012	31	%		44,430	31	%
Private Companies		97,057	58	%		84,343	59	%
Total contract revenues	$	166,620	100	%	$	143,105	100	%