Income Taxes (Details 3) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Accrued expenses	$ 27,000	$ 26,000
Allowance for doubtful accounts	1,000	1,000
Deferred revenue	7,000
Reserve for obsolescence	25,000	29,000
Expense associated with non-qualified stock options	94,000	90,000
Revenue Sharing Agreement	200,000	258,000
General business credit	1,378,000	1,337,000
NOL carryforward	11,377,000	11,084,000
Deferred tax assets, gross	13,109,000	12,825,000
Less: valuation allowance	(13,109,000)	(12,825,000)	$ (18,056,000)
Deferred tax asset, net