Quarterly report pursuant to Section 13 or 15(d)

Balance Sheet Components - Additional Information (Details)

v3.21.1
Balance Sheet Components - Additional Information (Details)
3 Months Ended
Mar. 31, 2021
USD ($)
Customer
Mar. 31, 2020
USD ($)
Customer
Dec. 31, 2020
USD ($)
Schedule Of Balance Sheet Components [Line Items]      
Unbilled Receivables $ 569,000   $ 459,000
Accounts receivable, net $ 38,425,000   29,717,000
Percentage of Non-US revenue invoiced in Euros 79.30% 68.70%  
Transfer of inventory to rental equipment $ 607,000 $ 368,000  
Salvage value of expenditures for additions, improvements and replacements 0    
Repairs and maintenance expense 935,000 524,000  
Depreciation and amortization 2,834,000 2,220,000  
Impairments of long-lived assets 0 0  
Impairment of finite lived intangible assets 0 0  
Goodwill impairment loss 0    
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 1,145,000   1,153,000
Customer Concentration Risk | Customer One      
Schedule Of Balance Sheet Components [Line Items]      
Accounts receivable, net 10,434,000   8,417,000
Customer Concentration Risk | Customer Two      
Schedule Of Balance Sheet Components [Line Items]      
Accounts receivable, net $ 8,102,000   $ 7,044,000
Sales Revenue, Net | Customer Concentration Risk      
Schedule Of Balance Sheet Components [Line Items]      
Number of customers | Customer 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 19.90% 23.60%  
Raw materials | Supplier Concentration Risk | Vendor two      
Schedule Of Balance Sheet Components [Line Items]      
Concentration risk, percentage 10.80% 15.20%  
Raw materials | Supplier Concentration Risk | Vendor three      
Schedule Of Balance Sheet Components [Line Items]      
Concentration risk, percentage 9.60% 9.40%