Accounts Receivable

12 Months Ended

Dec. 31, 2016

Receivables [Abstract]

Accounts Receivable

3. Accounts Receivable

(Table only in thousands)	2016			2015
Trade receivables	$	11,976		$	12,800
Contract receivables		72,835			86,129
Allowance for doubtful accounts		(1,749	)		(1,151	)
	$	83,062		$	97,778

Balances billed, but not paid by customers under retainage provisions in contracts, amounted to approximately $3.2 million and $2.3 million at December 31, 2016 and 2015, respectively. Retainage receivables on contracts in progress are generally collected within a year after contract completion.

Provision for doubtful accounts was approximately $0.8 million, $0.7 million and $0.3 million during 2016, 2015 and 2014, respectively, while accounts charged to the allowance were $0.3 million, $0.2 million and $0.3 million during 2016, 2015 and 2014, respectively.