Income Taxes (Schedule Of Net Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Vacation Accrual	$ 24	$ 24
Allowance for Doubtful Accounts	2	2
Stock Compensation	93	91
Bonus	2	0
Depreciation and Amortization	50	29
Inventory Obsolescence	4	2
R&D Credit Carryforward	171	154
Valuation allowance	(121)	(81)
Total Deferred Tax Assets	225	221
Prepaid Expenses	22	20
Net unrealized gain on investments	0	9
Total Deferred Tax Liabilities	22	29
Net Deferred Tax Asset	$ 203	$ 192