Accounts Receivable (Tables)

6 Months Ended

Jun. 30, 2017

Receivables [Abstract]

Schedule of Accounts Receivable

Accounts receivable consists of the following (in thousands):

	June 30, 2017			December 31, 2016
Trade accounts receivable	$	101,578		$	81,193
Contract receivables:
Amounts billed	35,658			41,569
Costs in excess of billings	7,007			6,582
Total contract receivables	42,665			48,151
Total accounts receivable	144,243			129,344
Less allowance for doubtful accounts	(5,372		)	(5,272		)
Accounts receivable	$	138,871		$	124,072