Income Taxes (Schedule Of Net Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Abstract]
Vacation Accrual	$ 24	$ 23
Allowance for Doubtful Accounts	2	2
Stock Compensation	91	88
Bonus	0	2
Depreciation and Amortization	29	17
Inventory Obsolescence	2	0
R&D Credit Carryforward	154	101
Valuation allowance	(81)	(28)
Total Deferred Tax Assets	221	205
Prepaid Expenses	20	20
Net unrealized gain on investments	9	3
Total Deferred Tax Liabilities	29	23
Net Deferred Tax Asset	$ 192	$ 182