Note 7 - Stockholders' Equity - Stock Options Activity (Details) - USD ($)	6 Months Ended		12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Outstanding, beginning balance (in shares)	4,225,537
Outstanding, weighted-average exercise price, beginning balance (in dollars per share)	$ 1.79
Outstanding, weighted-average remaining contractual life (Year)	3 years 146 days		4 years 36 days
Outstanding, aggregate intrinsic value	$ 31,125		$ 158,675
Granted, options (in shares)	294,500	100,000
Granted, weighted-average exercise price (in dollars per share)	$ 1
Outstanding, ending balance (in shares)	4,520,037		4,225,537
Outstanding, weighted-average exercise price, ending balance (in dollars per share)	$ 1.42		$ 1.79
Exercisable, options (in shares)	4,420,037
Exercisable, weighted-average exercise price (in dollars per share)	$ 1.44
Exercisable, weighted-average remaining contractual life (Year)	3 years 109 days
Exercisable, aggregate intrinsic value	$ 38,625