XML 75 R61.htm IDEA: XBRL DOCUMENT v3.21.1
Note F - Concentration of Risk (Details Textual)
12 Months Ended
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Cash, Uninsured Amount $ 16,020,000 $ 0
Customer Concentration Risk [Member] | Revenue Benchmark [Member]    
Concentration Risk, Number of Major Customers 1 2
Concentration Risk, Percentage 18.00%  
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer A [Member]    
Concentration Risk, Percentage   22.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer B [Member]    
Concentration Risk, Percentage   14.00%
Customer Concentration Risk [Member] | Non-current Accounts Receivable [Member]    
Concentration Risk, Number of Major Customers 1 3
Concentration Risk, Percentage 31.00%  
Customer Concentration Risk [Member] | Non-current Accounts Receivable [Member] | Customer A [Member]    
Concentration Risk, Percentage   18.00%
Customer Concentration Risk [Member] | Non-current Accounts Receivable [Member] | Customer B [Member]    
Concentration Risk, Percentage   16.00%
Customer Concentration Risk [Member] | Non-current Accounts Receivable [Member] | Customer C [Member]    
Concentration Risk, Percentage   14.00%