Note 5 - Share-Based Compensation - Stock Options Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Options outstanding - beginning of year (in shares)	638,000	645,000
Options outstanding - beginning of year (in dollars per share)	$ 0.38	$ 0.38
Options outstanding - beginning of year	2 years 251 days	3 years 273 days	4 years 288 days
Granted (in shares)
Granted, Weighted Exercise Price (in dollars per share)
Exercised (in shares)	(7,000)	(7,000)
Exercised, Weighted Exercise Price (in dollars per share)	$ 0.05	$ 0.05
Forfeited / Cancelled (in shares)
Forfeited / Cancelled, Weighted Exercise Price (in dollars per share)
Options outstanding - end of year (in shares)	631,000	638,000	645,000
Options outstanding - end of year (in dollars per share)	$ 0.38	$ 0.38	$ 0.38
Options exercisable - December 31, 2015 (in shares)	610,000	610,000
Options exercisable - December 31, 2015 (in dollars per share)	$ 0.39	$ 0.39
Options exercisable - December 31, 2015	2 years 204 days	3 years 204 days