Quarterly report pursuant to Section 13 or 15(d)

Balance Sheet Components - Additional Information (Details)

v3.19.3
Balance Sheet Components - Additional Information (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2019
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2019
USD ($)
Customer
Sep. 30, 2018
USD ($)
Customer
Dec. 31, 2018
USD ($)
Schedule Of Balance Sheet Components [Line Items]          
Unbilled Receivables $ 580,000   $ 580,000   $ 589,000
Accounts receivable, net $ 41,180,000   $ 41,180,000   37,041,000
Percentage of Non-US revenue invoiced in Euros 70.30% 77.20% 71.20% 76.70%  
Salvage value of expenditures for additions, improvements and replacements $ 0   $ 0    
Repairs and maintenance expense 938,000 $ 545,000 2,301,000 $ 1,734,000  
Depreciation and amortization 2,393,000 2,380,000 7,295,000 7,592,000  
Impairments of long-lived assets     0 0  
Impairment of finite lived intangible assets     0 0  
Amortization of intangible assets 1,269,000 $ 332,000 1,921,000 929,000  
Construction in Process and Computer Software or Development Cost          
Schedule Of Balance Sheet Components [Line Items]          
Depreciation and amortization     0 $ 0  
Other Noncurrent Assets          
Schedule Of Balance Sheet Components [Line Items]          
Noncurrent inventories expected to be realized or consumed 828,000   828,000   1,085,000
Customer Concentration Risk | Customer One          
Schedule Of Balance Sheet Components [Line Items]          
Accounts receivable, net 16,379,000   16,379,000   16,198,000
Customer Concentration Risk | Customer Two          
Schedule Of Balance Sheet Components [Line Items]          
Accounts receivable, net $ 6,504,000   $ 6,504,000   $ 4,155,000
Sales Revenue, Net | Customer Concentration Risk          
Schedule Of Balance Sheet Components [Line Items]          
Number of customers | Customer     0 1  
Net Accounts Receivable | Customer Concentration Risk          
Schedule Of Balance Sheet Components [Line Items]          
Number of customers | Customer     2    
Raw materials | Supplier Concentration Risk | Vendor one          
Schedule Of Balance Sheet Components [Line Items]          
Concentration risk, percentage     22.10% 19.80%  
Raw materials | Supplier Concentration Risk | Vendor two          
Schedule Of Balance Sheet Components [Line Items]          
Concentration risk, percentage     13.80% 12.60%  
Raw materials | Supplier Concentration Risk | Vendor three          
Schedule Of Balance Sheet Components [Line Items]          
Concentration risk, percentage     9.70% 9.60%