Quarterly report pursuant to Section 13 or 15(d)

Balance Sheet Components - Additional Information (Details)

v3.20.2
Balance Sheet Components - Additional Information (Details)
 3 Months Ended 6 Months Ended
Jun. 30, 2020
USD ($)
Jun. 30, 2019
USD ($)
Jun. 30, 2020
USD ($)
Customer
Jun. 30, 2019
USD ($)
Customer
Dec. 31, 2019
USD ($)
Schedule Of Balance Sheet Components [Line Items]          
Unbilled Receivables $ 1,520,000   $ 1,520,000   $ 590,000
Accounts receivable, net $ 28,422,000   $ 28,422,000   34,325,000
Percentage of Non-US revenue invoiced in Euros 77.20% 71.80% 72.20% 71.60%  
Transfer of inventory to rental equipment     $ 1,193,000 $ 670,000  
Salvage value of expenditures for additions, improvements and replacements $ 0   0    
Repairs and maintenance expense 598,000 $ 701,000 1,123,000 1,363,000  
Depreciation and amortization 2,230,000 2,436,000 4,450,000 4,902,000  
Impairments of long-lived assets     0 0  
Impairment of finite lived intangible assets     0 0  
Amortization of intangible assets 2,250,000 $ 324,000 4,492,000 652,000  
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 2,091,000   2,091,000   1,076,000
Customer Concentration Risk | Customer One          
Schedule Of Balance Sheet Components [Line Items]          
Accounts receivable, net 5,866,000   5,866,000   10,695,000
Customer Concentration Risk | Customer Two          
Schedule Of Balance Sheet Components [Line Items]          
Accounts receivable, net $ 8,900,000   $ 8,900,000   $ 5,228,000
Sales Revenue, Net | Customer Concentration Risk          
Schedule Of Balance Sheet Components [Line Items]          
Number of customers | Customer     1 0  
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     21.40% 21.50%  
Raw materials | Supplier Concentration Risk | Vendor two          
Schedule Of Balance Sheet Components [Line Items]          
Concentration risk, percentage     10.60% 13.10%  
Raw materials | Supplier Concentration Risk | Vendor three          
Schedule Of Balance Sheet Components [Line Items]          
Concentration risk, percentage     10.40% 9.30%