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Concentration of Credit Risk (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2016
USD ($)
Customer
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Concentration Risk [Line Items]      
Industry practice payment of receivables 20 days    
Percentage of U.S. demand supplied by company 1.00%    
Changes in the allowance for doubtful accounts [Roll Forward]      
Balance, beginning of year $ 206 $ 179 $ 252
Provisions for bad debts 100 116 50
Less: Write-offs and recoveries (81) (89) (123)
Balance, end of year $ 225 $ 206 $ 179
Customer Concentration Risk [Member] | Minimum [Member]      
Concentration Risk [Line Items]      
Number of customers | Customer 3    
Customer Concentration Risk [Member] | Maximum [Member]      
Concentration Risk [Line Items]      
Number of customers | Customer 5    
Accounts Receivable [Member] | Product Concentration Risk [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 90.00%    
Accounts Receivable [Member] | Customer One [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 20.90% 20.30% 16.60%
Accounts Receivable [Member] | Customer Two [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 14.00% 16.50% 16.60%
Accounts Receivable [Member] | Customer Three [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 10.10% 12.70% 10.40%
Accounts Receivable [Member] | Customer Four [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 0.00% 0.00% 0.00%
Revenue [Member] | Customer Concentration Risk [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 50.00%    
Revenue [Member] | Customer One [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 18.20% 24.40% 20.30%
Revenue [Member] | Customer Two [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 16.50% 13.80% 14.00%
Revenue [Member] | Customer Three [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 15.90% 0.00% 0.00%
Revenue [Member] | Customer Four [Member]      
Concentration Risk [Line Items]      
Concentration risk, percentage 10.60% 0.00% 0.00%