Accounts Receivable (Tables)

6 Months Ended

Jun. 30, 2018

Receivables [Abstract]

Schedule of Accounts Receivable

Accounts receivable consists of the following (in thousands):

	June 30, 2018			December 31, 2017
Trade accounts receivable	$	157,944		$	140,209
Costs in excess of billings	20,163			11,610
Total accounts receivables	178,107			151,819
Less allowance for doubtful accounts	(6,465		)	(6,434		)
Accounts receivable	$	171,642		$	145,385