Accounts Receivable and Allowance for Doubtful Accounts - Schedule of Accounts Receivable (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Receivables [Abstract]    
Trade accounts receivable $ 35,039 $ 42,296
Other receivables 4,244 2,793
Costs in excess of billings 1,704 0
Gross accounts receivable 40,987 45,089
Less: allowance for doubtful accounts (467) (739)
Net accounts receivable $ 40,520 $ 44,350