Debt / Line of Credit (Narrative) (Details) - USD ($)		12 Months Ended
	Dec. 21, 2016	Dec. 31, 2019	Dec. 31, 2018
Line of Credit Facility [Line Items]
Interest paid, capitalized or accrued		$ 82,000	$ 82,000
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		7.75%
Renewal date		Dec. 31, 2019
Automatic renewal date		Dec. 31, 2020
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		$ 1,200,000
Minimum [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Minimum interest rate	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%