Stockholders' Equity - Schedule of Share-based Compensation, Stock Options, Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Note 9 - Stockholders' Equity (Details) - Summary of Status of All Stock Option Plans [Line Items]
Options Outstanding, Beginning Balance	388,610	409,878
Options Outstanding, Granted
Options Outstanding, Exercised		1,800
Options Outstanding, Ending Balance	194,612	388,610
Stock Option Plans [Member]
Note 9 - Stockholders' Equity (Details) - Summary of Status of All Stock Option Plans [Line Items]
Options Outstanding, Beginning Balance	684,722	705,990
Options Outstanding, Granted
Options Outstanding, Exercised		(1,800)
Options Outstanding, Forfeited or expired	(369,555)	(19,468)
Options Outstanding, Ending Balance	315,167	684,722
Options Outstanding, Exercisable at year-end	315,167	684,722
Options Outstanding, Vested or expected to vest at year-end	315,167	684,571
Weighted Average Exercise Price, Outstanding Beginning Balance	$ 2.64	$ 2.63
Weighted Average Exercise Price, Granted
Weighted Average Exercise Price, Exercised		0.81
Weighted Average Exercise Price, Forfeited or expired		2.74
Weighted Average Exercise Price, Outstanding Ending Balance	2.46	2.64
Weighted Average Exercise Price, Exercisable at year-end	2.46	2.64
Weighted Average Exercise Price, Vested or expected to vest at year-end	$ 2.46	2.64
Weighted average fair value of options granted during the period		$ 2.64