Debt / Line of Credit (Narrative) (Details) - USD ($)
 12 Months Ended
Dec. 21, 2016
Dec. 31, 2021
Dec. 31, 2020
Jun. 08, 2020
Line of Credit Facility [Line Items]        
Interest paid, capitalized or accrued   $ 58,000    
Paycheck Protection Program [Member]        
Line of Credit Facility [Line Items]        
Minimum interest rate       1.00%
Loans payable       $ 1,900,000
Revolving Credit Facility [Member]        
Line of Credit Facility [Line Items]        
Borrowing capacity description   provides for up to a maximum amount of $5 million based on a borrowing base equivalent of 85% of eligible accounts receivable plus the lesser of $2 million or 50% of eligible inventory.    
Maximum borrowing capacity $ 5,000,000      
Borrowing base equivalent of eligible accounts receivable, percentage 85.00%      
Monthly interest payment $ 2,000      
Monthly administrative fee $ 1,000      
Annual facility fee on maximum amount borrowable 1.00%      
Effective interest rate of funds borrowed   6.50%    
Renewal date   Dec. 31, 2021    
Automatic renewal date   Dec. 31, 2022    
Line of credit facility term 3 years      
Automatic renewal term   1 year    
Debt issuance costs $ 200,000      
Minimum tangible net worth required for compliance 13,000,000      
Minimum working capital required for compliance $ 4,000,000      
Remaining borrowing capacity   $ 2,300,000    
Outstanding amount on credit facility   $ 1,974,000 $ 1,875,000  
Minimum [Member] | Revolving Credit Facility [Member]        
Line of Credit Facility [Line Items]        
Effective interest rate of funds borrowed 6.50%      
Maximum [Member] | Revolving Credit Facility [Member]        
Line of Credit Facility [Line Items]        
Borrowing base equivalent of eligible inventory $ 2,000,000      
Borrowing base equivalent of eligible inventory, percentage 50.00%      
Prime Rate [Member] | Revolving Credit Facility [Member]        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 3.00%