Note 4 - Summary of Stock Options (Details)	6 Months Ended
	Jun. 30, 2016 USD ($) $ / shares shares
Shares outstanding (in shares) | shares	286,500
Shares outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 1.83
Shares outstanding, weighted average remaining contractual life	5 years 73 days
Shares outstanding, aggregate intrinsic value | $	$ 541,530
Shares vested and exercisable (in shares) | shares	268,500
Shares vested and exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 1.74
Shares vested and exercisable, weighted average remaining contractual life	4 years 328 days
Shares vested and exercisable, aggregate intrinsic value | $	$ 534,390