Quarterly report pursuant to Section 13 or 15(d)

Balance Sheet Components - Additional Information (Details)

v3.4.0.3
Balance Sheet Components - Additional Information (Details)
3 Months Ended 12 Months Ended
Mar. 31, 2016
USD ($)
Customer
Mar. 31, 2015
USD ($)
Customer
Dec. 31, 2015
USD ($)
Customer
Schedule Of Balance Sheet Components [Line Items]      
Unbilled Receivables $ 5,067,000   $ 5,155,000
Accounts Receivable Net Current $ 23,748,000   19,872,000
Percentage of Non-US revenue invoiced in Euros 68.30% 22.00%  
Salvage value of expenditures for additions, improvements and replacements $ 0    
Repairs and maintenance expense 687,000 $ 570,000  
Depreciation and amortization 3,425,000 3,423,000  
Impairments of long-lived assets 0 0  
Impairment of finite lived intangible assets 0 0  
Amortization of intangible assets 23,000 21,000  
Construction in Process and Computer Software or Development Cost      
Schedule Of Balance Sheet Components [Line Items]      
Depreciation and amortization 0 $ 0  
Customer Concentration Risk      
Schedule Of Balance Sheet Components [Line Items]      
Accounts Receivable Net Current $ 7,432,000   $ 7,441,000
Sales Revenue, Net | Customer Concentration Risk      
Schedule Of Balance Sheet Components [Line Items]      
Number of customers | Customer 0 0  
Concentration risk, percentage 19.50% 26.00%  
Accounts Receivable | Customer Concentration Risk      
Schedule Of Balance Sheet Components [Line Items]      
Number of customers | Customer 0   0
Concentration risk, percentage 31.30%   37.40%
Sales Revenue, Services, Net | Customer Concentration Risk      
Schedule Of Balance Sheet Components [Line Items]      
Concentration risk, percentage 82.20% 82.10%  
Raw materials | Supplier Concentration Risk | Vendor one      
Schedule Of Balance Sheet Components [Line Items]      
Concentration risk, percentage 14.10% 22.70%  
Raw materials | Supplier Concentration Risk | Vendor two      
Schedule Of Balance Sheet Components [Line Items]      
Concentration risk, percentage 11.80% 18.00%  
Raw materials | Supplier Concentration Risk | Vendor three      
Schedule Of Balance Sheet Components [Line Items]      
Concentration risk, percentage 7.10% 5.80%