Quarterly report pursuant to Section 13 or 15(d)

Organization and Summary of Significant Accounting Policies (Details Textual)

v3.20.2
Organization and Summary of Significant Accounting Policies (Details Textual) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
May 04, 2020
Mar. 31, 2020
Mar. 31, 2019
Dec. 31, 2019
Dec. 31, 2018
Organization and Summary of Significant Accounting Policies (Textual)          
Net sales   89.00%   95.00%  
Cash on hand   $ 899 $ 3,534 $ 2,840 $ 5,640
Inventory reserves   600   600  
Operating lease right-of-use assets   2,033 2,641 2,187  
Operating lease liabilities   2,130 $ 2,676    
Warranty reserve   $ 375   $ 375 $ 175
Vendor One [Member] | Accounts Payable [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   9.00% 11.00%    
Vendor Two [Member] | Accounts Payable [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   7.00% 10.00%    
Vendor Three [Member] | Accounts Payable [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   6.00%      
Revenues [Member] | Tier-1 telecommunications wireless carriers [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   6.00% 3.00%    
Revenues [Member] | Tier-1 telecommunications wireless carriers [Member] | Customer One [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   69.00% 60.00%    
Revenues [Member] | Tier-1 telecommunications wireless carriers [Member] | Customer Two [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   15.00% 27.00%    
Revenues [Member] | Sales to Telecommunications Customers [Member] | Customer One [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   95.00% 94.00%    
Accounts Receivable [Member] | Customer One [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   48.00%   70.00%  
Accounts Receivable [Member] | Customer Two [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Concentration risk   41.00%   6.00%  
Subsequent Event [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Aggregate principal amount $ 1,715        
Australian Dollars [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Cash   $ 7   $ 18  
Romanian Leu [Member]          
Organization and Summary of Significant Accounting Policies (Textual)          
Cash   $ 27   $ 4