Concentration of Risk and Enterprise-Wide Disclosures (Tables)

12 Months Ended

Dec. 31, 2021

Trade and contract retainage receivables

Concentration Risk [Line Items]

Schedules of concentration of risk, by risk factor

	December 31, 2021				December 31, 2020
Federal Government	$	6,563	5	%	$	4,826	4	%
State Governments		61	-	%		—	-	%
Local Governments		11,923	9	%		17,823	13	%
Private Companies		111,328	86	%		110,616	83	%
Gross receivables		129,875	100	%		133,265	100	%
Allowance for credit losses		(323)				(411)
Net receivables	$	129,552			$	132,854

Contract revenues

Concentration Risk [Line Items]

Schedules of concentration of risk, by risk factor

	2021		%		2020		%		2019		%
Federal Government	$	54,480	9	%	$	51,793	7	%	$	46,425	6	%
State Governments		4,790	1	%		27,574	4	%		47,831	7	%
Local Government		120,311	20	%		202,839	29	%		212,958	30	%
Private Companies		421,779	70	%		427,736	60	%		401,176	57	%
Total contract revenues	$	601,360	100	%	$	709,942	100	%	$	708,390	100	%