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Business Description and Summary of Significant Accounting Policies - Additional Information (Details)
9 Months Ended 12 Months Ended
Sep. 30, 2020
USD ($)
Y
Sep. 30, 2019
USD ($)
Dec. 31, 2019
USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Allowance for doubtful accounts $ 188,000   $ 337,000
Warranty period 27 months    
Warranty reserve $ 287,000   420,000
Inventory reserve 1,677,000   1,437,000
Income taxes paid 425,000 $ 0  
Interest paid 116,000 $ 88,000  
Impairment of long-lived assets $ 0   $ 0
Minimum      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Period inventory is expected to be used 2 years    
Number of years of customer requirements | Y 1    
Number of year's supply | Y 1