Annual report pursuant to Section 13 and 15(d)

Organization and Summary of Significant Accounting Policies (Details Textuals)

v3.19.3.a.u2
Organization and Summary of Significant Accounting Policies (Details Textuals)
$ in Thousands
 12 Months Ended
Jan. 01, 2019
USD ($)
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
New Accounting Pronouncement, Early Adoption [Line Items]          
Number of Operating Segments   1      
Standard Product Warranty Accrual, Current   $ 600 $ 500    
Revenue, Performance Obligation, Payment Term   30 days      
Impairment losses   $ 0 2,198 $ 2,000  
Revenue, Performance Obligation, Delivery Term   1 year      
Contract with Customer, Right of Return Term   6 months      
Assets [Member]          
New Accounting Pronouncement, Early Adoption [Line Items]          
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification $ 24,800        
Liability [Member]          
New Accounting Pronouncement, Early Adoption [Line Items]          
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification $ 25,100        
SEC Schedule, 12-09, Allowance, Credit Loss [Member]          
New Accounting Pronouncement, Early Adoption [Line Items]          
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount   $ 0 $ 46 $ 73 $ 87
Minimum [Member]          
New Accounting Pronouncement, Early Adoption [Line Items]          
Property, Plant and Equipment, Useful Life   2 years      
Revenue, Performance Obligation, Warranty Term   1 year      
Contract with Customer, Rebate and Price Protection Program Term   1 year      
Maximum [Member]          
New Accounting Pronouncement, Early Adoption [Line Items]          
Property, Plant and Equipment, Useful Life   5 years      
Revenue, Performance Obligation, Warranty Term   3 years      
Contract with Customer, Rebate and Price Protection Program Term   2 years